Friston on Freud

An ambitious, speculative 2010 paper co-authored by Karl Friston attempts to tie together Sigmund Freud’s psychoanalytic descriptions of the ‘id’ and the ‘ego’ with modern neurobiological accounts of self-organized hierarchical cortical systems – such as Friston’s own ‘variational free energy’ theory:

Carhart-Harris, R. L. & Friston, K. J. (2010). The default-mode, ego-functions and free-energy: a neurobiological account of Freudian ideas. Brain133: 1265–1283. DOI: 10.1093/brain/awq01

A PDF of the paper is available on Friston’s UCL pages here but it is not searchable and there is supplementary material hidden away in a zip file. Here, I just present the information of the whole paper including the supplementary material in a single web page.

Some commentators on this paper are:

The default-mode, ego-functions and free-energy: a neurobiological account of Freudian ideas

R. L. Carhart-Harris1 and K. J. Friston2

1 Neuropsychopharmacology Unit, Imperial College London, Hammersmith Campus, Du Cane Road, London, UK

2 The Wellcome Trust Centre for Neuroimaging, 12 Queen Square, London, UK

Correspondence to: R. L. Carhart-Harris,

Neuropsychopharmacology Unit,

Imperial College London,

Hammersmith Campus,

Du Cane Road,





Received August 16, 2009. Revised and Accepted December 23, 2009.

The Author(s) 2010. Published by Oxford University Press on behalf of Brain.

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Brain Advance Access published February 28, 2010


This article explores the notion that Freudian constructs may have neurobiological substrates. Specifically, we propose that Freud’s descriptions of the primary and secondary processes are consistent with self-organized activity in hierarchical cortical systems and that his descriptions of the ego are consistent with the functions of the default-mode and its reciprocal exchanges with subordinate brain systems. This neurobiological account rests on a view of the brain as a hierarchical inference or Helmholtz machine. In this view, large-scale intrinsic networks occupy supra-ordinate levels of hierarchical brain systems that try to optimize their representation of the sensorium. This optimization has been formulated as minimizing a free-energy; a process that is formally similar to the treatment of energy in Freudian formulations. We substantiate this synthesis by showing that Freud’s descriptions of the primary process are consistent with the phenomenology and neurophysiology of rapid eye movement sleep, the early and acute psychotic state, the aura of temporal lobe epilepsy and hallucinogenic drug states.


  • Freud
  • the ego
  • default-mode
  • prediction
  • free-energy


  • BOLD = blood oxygen level dependent;
  • DMN = default-mode network;
  • fMRI = functional magnetic resonance imaging;
  • REM = rapid eye movement


In this synthesis we explore the notion that Freudian constructs may have real neurobiological substrates and could be usefully revisited in the context of modern neuroscience. It is worth noting that Freud had a formal training in neuroanatomy and was influenced by people like Helmholtz, who laid many of the foundations for theoretical neurobiology. Advances in empirical and theoretical neuroscience now allow us to recast some central Freudian ideas in a mechanistic and biologically informed fashion. Specifically, we note that the psychoanalytic distinction between the primary and secondary processes (as functions of the id and ego respectively) fit comfortably with modern notions of functional brain architecture, at both a computational and neuro-physiological level. Although this may seem a rather abstract and ambitious synthesis, there is in fact an enormous amount of empirical evidence from neuropsychology, neuroimaging and psychopharmacology to support it.

In what follows we attempt to demonstrate consistencies between key Freudian ideas and recent perspectives on global brain function that have emerged in imaging and theoretical neuroscience. The intention is to demonstrate and develop the construct validity of the Freudian concepts. This should allow Freudian concepts to be operationalized and measured empirically and could enable a dialogue between psychoanalysts and neuro-biologists. This may have implications for psychiatry to the extent that mechanistic theories of psychopathology appeal to either neurobiological or psychoanalytical constructs. We start by summarizing the key elements of the three areas that we want to relate to each other; namely the central Freudian constructs, the Helmholtzian or Bayesian brain framework and empirical findings from neuroimaging on the global organization of brain activity.

The primary and secondary process

Freud came to a realization that there are two fundamentally different modes of cognition (the primary and secondary process) through a study of ‘altered’ or ‘non-ordinary’ states of consciousness (e.g. Q115, Q333 and Q462 in Supplementary material). He recognized in certain non-ordinary states (e.g. dreaming and psychosis) a mode of cognition that is characterized by a primitive, animistic style of thinking. Freud conjectured that the exchange of neuronal energy is relatively ‘free’ in this mode and he named this the ‘primary process’. Simultaneously, Freud recognized in non-ordinary states the loss of certain functions, which are normally present in waking cognition. He ascribed these functions to a central organization (the ego) which works to minimize the mind’s free-energy. Freud named this function the ‘secondary process’ and defined its aim as one of converting ‘free energy’ into ‘bound energy’ (for a more thorough discussion of these central concepts of Freudian theory see the supporting quotes in the online Supplementary material, cited in Table 1): We seem to recognize that nervous or psychical energy occurs in two forms, one freely mobile and another, by comparison, bound; we speak of [activations] and [hyperactivations] of psychical material, and even venture to suppose a [hyperactivation] brings about a kind of synthesis of different processes — a synthesis in the course of which free energy is transformed into bound energy We hold firmly to the view that the distinction between the [primary] and the [secondary] state lies in dynamic relations of this kind, which would explain how it is that, whether spontaneously or with our assistance, the one can be changed into the other We have found that processes in the unconscious or in the id obey different laws from those in the ego. We name these laws in their totality the primary process, in contrast to the secondary process which governs the course of events in the ego. (Q461, Freud, 1940)

Table 1

List of quotations pertaining to the characteristics of the secondary process (and the ego) and primary process thinking (and the id). Q numbers refer to quotes given in the Supplementary material, below.

The ego and the secondary process: Relevant quotations from Freud

  1. Default energy store or reservoir, which possesses the property of being spontaneously or tonically active. Q5, Q15, Q109, Q154, Q162, Q209, Q273, Q298, Q300, Q301, Q314, Q320, Q321, Q416, Q438, Q454
  2. Receives and ‘contains’ or ‘represses’ endogenous excitation. Q1, Q15, Q46, Q80, Q132, Q152, Q154, Q183, Q205, Q209, Q212, Q219, Q283, Q283, Q287, Q328, Q358, Q363, Q391, Q392, Q427, Q427, Q429, Q437, Q448, Q475
  3. Minimizes free-energy. Q2, Q8, Q18, Q70, Q199, Q200, Q283, Q285, Q307, Q314, Q321, Q366, Q373, Q410, Q461, Q483
  4. Integrates or binds the primary process and its representational system (the id) into a broader, more cohesive, composite organization (the ego). Q15, Q29, Q45, Q46, Q154, Q209, Q218, Q231, Q233, Q234, Q237, Q300, Q302, Q308, Q314, Q315, Q334, Q339, Q351, Q358, Q360, Q383, Q384, Q385, Q391, Q397, Q402, Q413, Q429, Q447, Q461, Q483
  5. Specific ontogenetic development. Q47, Q113, Q174, Q273, Q300, Q301, Q358, Q414, Q440, Q459, Q486
  6. Supports reality-testing and perceptual processing. Q15, Q19, Q23, Q39, Q51, Q153, Q234, Q258, Q259, Q310, Q350, Q356, Q363, Q373, Q375, Q380, Q392, Q427, Q428, Q429, Q448, Q482, Q485
  7. Supports conscious awareness, cognition and directed attention. Q10, Q21, Q27, Q39, Q40, Q153, Q154, Q204, Q234, Q238, Q249, Q254, Q334, Q372, Q380, Q427
  8. Possesses internally and externally-focused components, which are inversely related (anti-correlated). Q6, Q39, Q162, Q173, Q204, Q243, Q273, Q289, Q300, Q301, Q320, Q329, Q363, Q438, Q448, Q454, Q484
  9. Excessive-engagement of internally-focused component and impoverished engagement of externally-focused network during pathological withdrawal; e.g. in depression and schizophrenia. Q144, Q147, Q158, Q161, Q168, Q169, Q170, Q172, Q244, Q252, Q253, Q263, Q265, Q266, Q267, Q277, Q288, Q292, Q293, Q297, Q301, Q329, Q330, Q368,
  10. Failure of systems to minimize free-energy (suppress endogenous excitation) results in disturbed affect, cognition and perception; as seen in non-ordinary states such as dreaming and psychosis. Q23, Q35, Q58, Q115, Q134, Q135, Q147, Q231, Q261, Q262, Q333, Q365, Q383, Q455, Q462, Q466, Q469, Q475, Q476, Q482, Q485

The id and primary process thinking: Relevant quotations from Freud:

  1. Characteristics of the system unconscious/the id and primary process thinking: i.e. a primitive, ‘magical’ or animisitic style of thinking, characterized neurophysiologically by ‘free’ movement of energy. One can think of primary process thinking in evolutionary terms as a ‘protoconsciousness’. Q58, Q63, Q90, Q92, Q97, Q115, Q135, Q151, Q160, Q171, Q198, Q201, Q203, Q209, Q211, Q216, Q217, Q218, Q228, Q229, Q230, Q231, Q233, Q237, Q241, Q242, Q247, Q249, Q254, Q257, Q261, Q270, Q279, Q280, Q282, Q299, Q305, Q311, Q315, Q335, Q359, Q388, Q389, Q396, Q397, Q423, Q424, Q425, Q426, Q437, Q440, Q442, Q443, Q446, Q453, Q461, Q465, Q467, Q468, Q470, Q471, Q472, Q474, Q477, Q479, Q480, Q482, Q490, Q491

The quotations can be found in Supplementary material.

Free-energy and the Bayesian brain

In terms of theoretical and computational neuroscience, we will focus on Helmholtz’s suggestion that the brain is an inference machine (Helmholtz, 1866; Dayan et al., 1995); this idea is now a fundamental premise in neurobiology (Gregory, 1968). Key examples of this include the Bayesian brain (Knill and Pouget, 2004), predictive-coding (Rao and Ballard, 1998) and the free-energy principle (Friston, 2009). This framework assumes that the brain uses internal hierarchical models to predict its sensory input and suggests that neuronal activity (and synaptic connections) try to minimize the ensuing prediction-error or (Helmholtz) free-energy. This free-energy is a measure of surprise and is essentially the amount of prediction-error. It is an information theory quantity that, mathematically, plays the same role as free-energy in statistical thermodynamics. Free-energy is not an abstract concept; it can be quantified easily and is used routinely in modelling empirical data (Friston et al., 2007) and in neuronal simulations of perception and action (Friston et al., 2009). The notion of a hierarchy is central here because it allows the brain to construct its own top-down prior expectations about sensory samples from the world. This resolves one of the key challenges facing the brain and also allows it to resolve ambiguities when inferring and representing the causes of exteroceptive and interoceptive sensations. Crucially, the hierarchical form of internal models (and associated neuroanatomy) (Felleman and Van Essen, 1991) entails a progression in the complexity of representations, as one proceeds up the hierarchy from thalamic nuclei and primary sensory cortex to association and paralimbic cortex (e.g. from sensations, through perceptions to concepts). This progression is reflected in the temporal extent of what is represented; with higher levels representing extended sequences of events that best account for the stream of sensory information represented in lower levels (see Kiebel et al., 2008 for a full discussion and simulations).

The hierarchical architecture may also accommodate the distinction between the Freudian primary and secondary processes, where the secondary process provides top-down predictions to reduce free-energy associated with the primary process (cf. converting free energy into bound energy). Under this mapping between Freudian and Helmholtzian models, one can link the energy associated with the primary process and the free-energy of Bayesian formulations. In both accounts, higher cortical areas are trying to organize activity in lower-levels through suppression of their free-energy.

Intrinsic brain networks and the default mode

Analyses of spontaneous Auctuations in the blood oxygen level dependent (BOLD) signal of functional magnetic resonance imaging (fMRI) during unconstrained ‘resting’ states (typically lying quietly with eyes closed or fixating on a cross) have identified a number of large-scale intrinsic networks (Beckmann et al., 2005; Damoiseaux et al., 2006). Of particular interest here is the so called ‘default-mode network’ (DMN), a network of regions that show high metabolic activity and blood flow at rest but which deactivate during goal-directed cognition (Raichle, 2001). Recent work has confirmed that the major nodes of the DMN are functionally and structurally connected (van den Heuvel et al., 2008; Greicius et al., 2009) and that this connectivity develops through ontogeny (Fair et al., 2008; Kelly et al., 2009). Another feature of the DMN is the inverse relationship of its neuronal activity with that of another large-scale intrinsic network; the ‘attention system’ (Fox et al., 2005; Fransson, 2005; Corbetta and Shulman, 2002). In this article, we pursue the idea that these intrinsic networks correspond to the high-levels of an inferential hierarchy, which function to suppress the free-energy of lower levels (i.e. suppress prediction errors with top-down predictions). We associate this optimization process with the secondary process. Furthermore, we associate failures of top-down control with non-ordinary states of consciousness, such as early and acute psychosis, the temporal-lobe aura, dreaming and hallucinogenic drug states. In what follows, we organize the evidence that speaks to the integration of neurobiological and psychoanalytic ideas and conclude with a defence of its value and potential utility. This article comprises three sections: in the first, we review evidence that the development and functioning of the DMN is consistent with ego-functions and the secondary process. We focus specifically on the DMN’s containment of endogenous excitation and its suppression of systems engaged by exogenous stimuli. In the second, we review evidence that a loss of top-down control over limbic activity in hierarchically lower systems is equivalent to a loss of the ego’s control over the primary process. In the final section, we discuss the clinical relevance of these ideas.

Large-scale intrinsic networks, the secondary process and ego

In this section, we introduce the idea that Freud’s descriptions of the development and functioning of the ego resonate with the development and functioning of the DMN and its reciprocal exchanges with subordinate brain systems. Freud’s first useful account of the ego was given in his posthumously published Project for a Scientific Psychology (Freud, 1895). Inspired by the recent introduction of ‘neurone theory’ by Cajal and Waldeyer-Harz, Freud hypothesized three functionally-distinct classes of neurone: the ‘w neurones’, which receive endogenous input and make up the ego; the ‘neurones’, which are sensitive to exogenous input; and the ‘x neurones’, which signal qualitative information. Although this neuronal classification system was abandoned by Freud soon after its conception, the ideas that inspired it remained a source of influence throughout his work. Several of Freud’s most important ideas were introduced and/or developed in the Project, including the notion that the ego is an organization that receives and contains/represses bottom-up endogenous excitation (Table 1, row 2; Q1, Q15, Q46 and Q429). The secondary process, or ‘secondary process cognition’, is the mode of cognition of the ego; put simply, it is the mode of normal waking consciousness of adult humans (e.g. Q317). Freud described the secondary process as ‘inhibited’ and ‘bound’; in contradistinction to the primary process which is ‘free’ and ‘motile’ (Freud, 1895, 1900). The concept of ‘bound’ energy was attributed by Freud to ideas first expressed by Breuer in their Studies on Hysteria (Breuer and Freud, 1895). Breuer conjectured the existence of a system of tonically active neurons, forming a ‘reservoir of nervous tension’ (e.g. Q45, Q154 and Q233). It is significant that the primary and secondary processes owe their inception to observations of non-ordinary states of consciousness (e.g. row 10, Table 1; Q23, Q35, Q115, Q333 and Q462). We shall see later that compelling evidence for the existence of two distinct modes of cognition can be found in studies of non-ordinary states. In what follows, we review the functional anatomy of the default-mode and related networks and then consider these networks from a theoretical perspective.

Functional anatomy of the default-mode

The notion of the DMN originated in a paper by Marcus Raichle reviewing a pattern of blood flow, glucose metabolism and oxygen consumption in the resting-state, which consistently decreases during goal-directed cognition (Raichle, 2001); in other words, a high-level distributed system whose activity is reciprocally related to the activity in cortical areas subserving task or stimulus-bound processing. Raichle proposed that this pattern reflects a default mode of brain function and a functionally relevant physiological baseline (Raichle, 2001). Subsequent work has associated activity in the network identified by Raichle and others (Greicius et al., 2003; Beckmann et al., 2005; Damoiseaux et al., 2006; Fransson and Marrelec, 2008; Wu et al., 2009) with phenomena such as self-referential processing, autobiographical recollection, mind-wandering and theory-of-mind (Gusnard et al., 2001; Vincent et al., 2006; Mason et al., 2007; Buckner et al., 2008; see also Q332). Regions specifically implicated in the DMN include the medial prefrontal cortex, the posterior cingulate cortex, the inferior parietal lobule, the lateral and inferior temporal cortex and the medial temporal lobes (Buckner et al., 2008; Fransson and Marrelec, 2008). Analyses of resting-state functional connectivity and diffusion tensor imaging have showed that the major nodes of the DMN are strongly interconnected (Greicius et al., 2003, 2009; Van den Heuvel et al., 2009) and that this connectivity matures through development (Fair et al., 2008; Kelly et al., 2009). Functional connectivity in the DMN is relatively weak in the elderly (Andrews-Hanna et al., 2007; Damoiseaux et al., 2008) and in patients with attention deficit disorder (Castellanos et al., 2008) and impulse control disorders (Church et al., 2009). Interestingly, medial prefrontal cortex-posterior cingulate cortex connectivity is entirely absent in infants (Fransson et al., 2007). These findings imply that the DMN develops through ontogeny, in a manner that parallels the emergence of ego-functions (Table 1, row 5). Model and data-driven analyses of resting-state functional connectivity, diffusion tensor imaging analyses of structural connectivity and anatomical work in primates suggest that the medial temporal lobes are connected to the medial prefrontal cortex and posterior cingulate cortex nodes of the DMN (Catani et al., 2003; Vincent et al., 2006; Buckner et al., 2008; Fransson and Marrelec, 2008; Kahn et al., 2008; Saleem et al., 2008; van den Heuvel et al., 2008; Robinson et al., 2009). This is important because the medial temporal lobes contain key structures (e.g. the hippocampal formation, the amygdala, parahippocampal gyrus and entorhinal cortex) that play a role in mnemonic and hedonic or emotional processing. The evidence suggests that medial prefrontal cortex-medial temporal lobe functional and structural connectivity increases through ontogeny (Eluvathingal et al., 2007; Kelly et al., 2009) with a notable increase at puberty (Benes et al., 1989). A recent study found reduced medial pre-frontal cortex-amygdala functional connectivity in patients with schizophrenia and an inverse correlation between connectivity and aggression in these patients (Hoptman et al., 2009). Preclinical work indicates that emotional extinction takes place via glutamatergic projections from the medial prefrontal cortex terminating on inhibitory interneurons in the medial temporal lobes (Rosenkranz and Grace, 2002; Rosenkranz et al., 2003) and a recent analysis of effective connectivity implied that activation of the rostral anterior cingulate drives inhibition of the amygdala in response to fearful faces (Stein et al., 2007). There is a huge amount of clinical and preclinical evidence supporting the limbic-suppressive function of the medial prefrontal cortex (Hariri et al., 2000; Milad and Quirk, 2002; Rosenkranz and Grace 2002; Phillips et al., 2003; Phelps et al., 2004; Etkin et al., 2006; Milad et al., 2006). Functional neuroimaging studies have correlated primitive thought and emotion with decreased activity in the medial prefrontal cortex and increased activity in the medial temporal lobes (Pietrini et al., 2000; Dougherty et al., 2004), while suppression of these behaviours correlated with medial prefrontal cortex activations (Pietrini et al., 2000; Beauregard et al., 2001; Dougherty et al., 2004). The recollection of distressing memories and emotions in patients with post-traumatic stress disorder has also been found to correlate with medial prefrontal cortex deactivations and medial temporal lobe activations (Bremner et al., 1999; Shin et al., 2004, 2006; Hopper et al., 2007) and the blockade of these memories also correlated with medial prefrontal cortex activations (Lanius et al., 2002; Reinders et al., 2003, 2006). Damage to the ventro-medial prefrontal cortex has long been associated with impaired impulse control (Grafmen et al., 1996; Anderson et al., 1999; Davidson et al., 2000; Kaplan-Solms and Solms, 2001; Solms and Turnbull, 2002). The medial prefrontal cortex sends dense projections to the ventral striatum (Ferry et al., 2000) and mid-brain (Carr and Sesack, 2000). The ventral striatum displays functional connectivity with the midbrain, medial temporal lobes and higher-level nodes of the DMN (Postuma and Dagher, 2006; Di Martino et al., 2008; Gutman et al., 2009) and the midbrain and ventral striatum signal prediction-error and motivational-salience (Robbins and Everitt, 1996; Berridge and Robinson, 1998; Schultz, 2002; Kapur, 2005). In summary, the DMN comprises high-level cortical nodes such as the medial prefrontal cortex that exchange neuronal signals with subcortical systems and other association and polymodal cortex, especially the systems responsible for emotional learning and memory. Much of the evidence suggests that activation of the DMN suppresses activity in lower systems. We now consider these aspects of functional anatomy in the light of hierarchical inference and the secondary process.

Figure 1


The DMN (yellow/orange) and attention system (blue): resting state functional connectivity of three seed regions: the dorsal medial prefrontal cortex, ventral medial prefrontal cortex and hippocampal formation (medial temporal lobes). Positive correlations (yellow–orange) with all seeds were evident in the posterior cingulate (PCC), posterior inferior parietal lobule (pIPL) and medial prefrontal cortex (mPFC). Regions negatively correlated with these seeds constitute the attention system and include the superior parietal lobule (SPL), intraparietal sulcus (IPS), the motion-sensitive middle temporal area (MT+), the frontal eye fields (FEF) the dorsal anterior cingulate (dACC), the dorsolateral prefrontal cortex (DLPFC), the ventral premotor cortex and the frontal operculum. Image reproduced from Buckner et al. (2008), with permission.

Theoretical formulations of the default mode

Freud argued that the ego modulates both endogenous and exogenous excitation. Empirically, this can be seen in early and acute psychosis, the aura of temporal lobe epilepsy and hallucinogenic states, where affective (e.g. fear), mnemonic (e.g. moments of deja vu or vivid recollection), perceptual (e.g. hallucinations) and cognitive (e.g. confused or muddled thinking) processing is perturbed (Bleuler, 1911; Epstein and Ervin, 1956; Cohen, 1964; Vollenweider et al., 1997) (Table 1, row 10; e.g. Q462). He further hypothesized that the ontogenetic/phylogenetic evolution of healthy, adult waking cognition depends on the formation of an equilibrium between the pressing forces of the primary process (entailed by the id) and the counter forces of the secondary process (entailed by the ego) (e.g. Q116). This description is remarkably consistent with contemporary models of cognition based on hierarchical Bayesian inference and Helmholtzian free-energy; where backward connections from higher cortical areas work to minimize the free-energy of lower areas (Mumford, 1992; Rao and Ballard, 1999; Friston, 2003; Kiebel et al., 2009). Anatomically speaking, forward connections originate in supra-granular layers and terminate in layer four spiny stellate cells. They project from lower to higher-levels; e.g. from thalamic nuclei to primary sensory cortex or from secondary sensory cortex to tertiary sensory areas. Backward connections are more abundant and diffuse than forward connections and their effects are primarily modulatory. Backward connections originate in deep pyramidal cells (infragranular layers) of the cortex and target infra and supragranular layers of lower cortical areas. Based on Bayesian and Helmholtzian principles it has been proposed that forward connections convey prediction-errors that optimize representations in higher levels. These representations are then used to form predictions that are conveyed by backward connections to lower levels. These predictions suppress or cancel prediction-errors (free-energy) until they can be minimized no further (Friston, 2003, 2005). In this way, the brain optimizes its representation of the world by suppressing prediction-errors with reciprocal message passing between hierarchical levels to minimize free-energy. This suppression simply involves countering excitatory presynaptic inputs (from representational units to neurons encoding prediction-error) with top-down presynaptic inputs, mediated by inhibitory interneurons. When the representations at any level can be explained by top-down predictions from the level above, prediction-error is minimized and the representations are internally consistent over levels. The aim of this process is to optimize parsimonious explanations for what caused sensory input (Friston, 2003) and establish sensory predictions to guide action and behaviour (Friston et al., 2009). Crucially, this empirically-informed scheme (Sandell and Schiller, 1982; Girard and Bullier, 1989; Hupeu et al., 1998; Kleinschmidt et al., 1998; Murray et al., 2002; Lachaux et al., 2005; Chen et al., 2008) recapitulates Freud’s 19th century conception and in particular his principle of constancy: [We] have taken the view that the principle which governs all mental processes is a special case of Fechner’s ‘‘tendency towards stability’’, and have accordingly attributed to the mental apparatus the purpose of reducing to nothing, or at least of keeping as low as possible, the sums of excitation which flow in upon it. (Freud, 1924; Q366) It is significant that Freud cited as his inspiration for these ideas, Gustav Fechner, the founder of psychophysics and a contemporary of Helmholtz (e.g. Q307, Q353, Q366, Q379): the process of minimizing ‘the sums of excitation’ is exactly the same as minimizing the sum of squared prediction-error or free-energy in Helmholtzian schemes. This rests on the assumption that the brain explicitly encodes prediction-error with neuronal activity (excitation) that is suppressed or explained by backward (top-down) afferents. As mentioned above, Freud argued that the ego modulates and suppresses both exogenous and endogenous signals (Table 1, rows 2 and 6). In neurobiological terms, exogenous signals correspond to interoceptive and exteroceptive signals from thalamic and unimodal sensory areas that convey sensory signals (prediction-errors) to polymodal and medial temporal lobe structures. Endogenous signals could be equated with subsequent bottom-up prediction errors (excitation) arising in limbic and paralimbic systems, which are passed up to high-level polymodal cortical areas that comprise the nodes of the default-mode. Clearly, the principles that attend hierarchical inference under Helmholtzian schemes are generic and may apply to all hierarchically deployed brain systems. However, we will focus on the DMN; specifically, on medial prefrontal suppression of limbic and paralimbic activity, and associate this with the suppression of endogenous activity by the ego. We now consider how the ego modulates excitation evoked by stimuli from the external world.

Hierarchical brain systems

As discussed in the introduction, BOLD signal oscillations in the DMN are characterized by their inverse relation to those of another major intrinsic network, referred to as the attention system (Corbetta and Shulman, 2002; Fox et al., 2005; Fransson, 2005). As well as showing a spontaneous inverse relationship with the DMN, the attention system is activated during externally-directed cognition and deactivated during internally-directed cognition, whereas the opposite is true of the DMN (Buckner et al., 2008); implying a ‘give-and-take’ relationship (Raichle, 2009). Regions implicated in the attention system include the dorsolateral prefrontal cortex, the dorsal anterior cingulate cortex, the frontal eye fields, the extrastriate cortex (e.g. V5) the superior parietal lobule, the intraparietal sulcus and the ventral premotor cortex (Buckner et al., 2008). These regions are active during target detection, attention to spatial detail and hand-eye coordination (Corbetta and Shulman, 2002; Shulman, 2003). Moreover, many of these nodes have been associated with top-down control of primary sensory input (Friston and But chel, 2000; Lachaux et al., 2005). High-level association cortices not only receive feedforward signals from sensory regions but also anticipate and reciprocate these inputs with backward connections conferring context-specificity and higher-level constraints (i.e. predictions) (Rao and Ballard, 1999; Friston, 2003, 2005; Angelucci and Bressloff, 2006). Recent work has suggested that what we have referred to as the ‘attention system’ is in fact not a unified system. Based on independent component analyses of resting state BOLD activity, Seeley et al. (2007) have shown that the system described by Fox et al. (2005) and Fransson (2005) can be differentiated into a ‘salience system’ which includes the dorsal anterior cingulate cortex, frontoinsular cortices, amygdala and ventral mid-brain; and a more dorsal and lateral cortical system (the ‘dorsal attention system’) which includes the dorsolateral prefrontal cortex, frontal eye fields, dorsal medial prefrontal cortex, intraparietal sulcus and superior parietal lobule. BOLD signal oscillations in both systems exhibit an inverse relationship with those in the posterior cingulate cortex of the DMN (Greicius et al., 2003) but the systems do not appear to be well integrated with each other. This differentiation has also been suggested by others (He et al., 2007; Dosenbach et al., 2008; Sridharan et al., 2008; Vincent et al., 2008). The picture that emerges is of a hierarchy of brain systems with the DMN at the top and the salience and dorsal attention systems at intermediate levels, above thalamic and unimodal sensory cortex. Under a Helmholtzian model, each system is trying to suppress the free-energy of its subordinates, through a process of optimizing predictions to reduce prediction-errors. This rests on recurrent message-passing between these systems that leads to self-organized activation patterns with a characteristic reciprocity or ‘give-and-take’ among levels. In this view, activation of the attention system may facilitate the suppression of exogenous excitation (Q258). Similarly, the DMN furnishes top-down control of the attentional and salience systems by explaining and thereby suppressing their activity. We next address the physiological basis of message-passing or interactions among brain regions that mediate this self-organized suppression.

Spontaneous BOLD oscillations and neuronal activity

Until recently, there had been some uncertainty about whether spontaneous BOLD-signal oscillations are generated by neuronal activity or non-neuronal physiological processes (Wise et al., 2004; Birn et al., 2006). Recent work has shown that spontaneous BOLD oscillations most probably have a neuronal origin (He et al., 2008; Nir et al., 2008; Shmuel and Leopold, 2008). Simultaneous fMRI and intracranial recordings in monkeys (Shmuel and Leopold, 2008) and humans (Nir et al., 2007) have identified spontaneous neuronal fluctuations that correlate with spontaneous BOLD fluctuations (Shmuel and Leopold, 2008). The neuronal fluctuations, which are coherent across the hemispheres, were evident in multi-unit firing rates and local field potential gamma power. Stimulus evoked BOLD activations have also been shown to correlate positively with gamma power (Niessing et al., 2005). Gamma has been associated with attention, feature-binding and expectancy (Singer and Gray, 1995; Herrmann, 2000; Engel et al., 2001). This suggests that BOLD fluctuations reflect cortical coherence associated with gamma and secondary process cognition, particularly since the gamma frequency, recorded in higher-level cortical areas, has recently been shown to suppress lower frequencies in lower-level cortical areas (Chen et al., 2009). This leads us to predict that the fluctuations in gamma power evident in the large-scale intrinsic networks index the ongoing minimization of free-energy in subordinate levels of the hierarchy (Engel et al., 2001; Raichle, 2007) and could provide an empirical measure of the secondary process. Generally speaking, oscillatory processes are ubiquitous in the brain and serve to couple remote neuronal populations. High frequency gamma has often been implicated in perceptual synthesis and binding (e.g. Singer, 2009); while theta rhythms have been most studied in the hippocampal system, where they are associated with (spatial) memory and exploration (e.g. Lisman and Redish, 2009). Crucially, theta and gamma are themselves coupled (e.g. Sirota et al., 2008), where slower theta oscillations may provide a temporal frame of reference for faster computations mediated at gamma frequencies. We will return to the oscillations and frequency-specific coupling in the brain in the next section. So far we have discussed the importance of reciprocal or anti-correlated activity in the DMN and networks for goal-directed cognition. However, it should be noted that spontaneous fluctuations in the DMN continue during active cognition, just as spontaneous fluctuations in the dorsal attention system continue during rest (Hampson et al., 2002; Beckmann et al., 2005; Damoiseaux et al., 2006; Fox et al., 2007). This tonicity presumably primes structures to infer exogenous inputs (Fox et al., 2007; Raichle, 2007) and supports a background level of predictive coding (Hampson et al., 2002). Furthermore, spontaneous fluctuations in the BOLD signal, which can be as large in amplitude as evoked BOLD responses (Fox et al., 2007), have been shown to reflect variations in behaviour (Boly et al., 2007; Fox et al., 2007). Much of the brain’s vast energy budget is reserved for spontaneous neuronal activity (Fox and Raichle, 2007; Raichle, 2007). We speculate that spontaneous activity in the DMN reflects the constant containment of spontaneous endogenous activityO commensurate with Freud’s concept of repression (Q209), while spontaneous activity in the dorsal attention system indexes the continual monitoring and suppression of exogenous stimuli. This conjecture appeals to the Helmholtzian view of the brain as an inference engine that continually generates predictions and hypotheses that, when freed from the present (Kiebel et al., 2009), necessarily entails the past and future. In addition to the functional importance of spontaneous neuronal activity in intrinsic networks, the give-and-take between the default system and task-positive systems appears to be vital for active cognition and conscious awareness (Pomarol-Clotet et al., 2008; He and Raichle, 2009; Whitfield-Gabrieli et al., 2009). Functional connectivity within the DMN has been shown to increase through ontogeny (Fair et al., 2008; Kelly et al., 2009), decrease in ageing (Andrews-Hanna et al., 2007; Damoiseaux et al., 2008) and to be underdeveloped in patients with impaired impulse control (Church et al., 2009). These findings imply that functional connectivity in the DMN (Hampson et al., 2006) and the dorsal attention system (Seeley et al., 2007) provides an index of cognitive aptitude but not necessarily active cognition (Larson-Prior et al., 2009). Ineffective deactivation of the DMN has been associated with cognitive error in healthy subjects (Li et al., 2007; Eichele et al. 2008) and negative symptoms in schizophrenia (Pomarol-Clotet et al., 2008; Whitfield-Gabrieli et al., 2009) and depression (Grimm et al., 2009; Sheline et al., 2009). Functional connectivity in the DMN is not significantly altered in sleep, sedation or coma (Boly et al., 2008; Larson-Prior et al., 2009) but the give-and-take between the DMN and its anti-correlated networks is (He and Raichle, 2009) (see Q238).

Figure 2


Resting state functional connectivity in three cortical networks: (i) dorsal attention system (DAS, blue) using voxels in the middle temporal area and superior parietal lobule as regions of interest; (ii) the salience system (light green) using voxels in the anterior PFC and anterior inferior parietal lobule as regions of interest; and (iii) the default mode network (orange) using the hippocampal formation and posterior inferior parietal lobule as regions of interest. Overlap between the networks is shown in dark green (salience system and DMN) and red (dorsal attention systems and salience system). Image used with permission from Justin Vincent and Randy Buckner.

Summary and synthesis

In this section, the secondary process was considered in relation to large-scale intrinsic networks working to predict and suppress excitation (Helmholtz free-energy) in subordinate systems. The concept of the secondary process entailed by ego-functions was associated with the suppressive effect of the DMN on its subcortical nodes and anti-correlated networks. Functional connectivity between limbic (e.g. the hippocampus and amygdala) structures and major nodes of the DMN during rest (Buckner et al., 2008; Di Martino et al., 2008) supports the notion that the systems enacting ego-functions have evolved to receive and control endogenous excitation that underlies mnemonic and hedonic processing. In the next section, we focus on the primary process and specifically how it is manifest in non-ordinary states of consciousness.

The phenomenology of primary process thinking

In this section we describe the phenomenology of non-ordinary states of consciousness that have been associated with primary process thinking. The primary process is not generally regarded as a serious topic of science but the phenomenology of certain non-ordinary states compel us to consider its importance. Psychoanalysis owes its origins to observations of non-ordinary states (Table 1, row 10; e.g. Q23, Q35, Q115, Q333; Q462). An early observation that has remained at the core of the Freudian model is that there exists in the mind an archaic mode of cognition, which under normal waking conditions is effectively suppressed (Q315). Freud saw this ‘primary’ mode as belonging to an ontogenetically and phylogenetically primitive system, which he referred to initially as ‘the unconscious’ (Breuer and Freud, 1895), later as ‘the system unconscious’, ‘system Ucs’ or just ‘Ucs’ (Freud, 1900, 1915 b) and eventually as ‘the it’ (Freud, 1923) (note: Freud’s original term for ‘the id’ was ‘das es’ and should really have been translated ‘the it’, just as his original term for ‘the ego’, ‘das Ich’, should have been translated ‘the I’; for simplicity however, we will use the familiar terms ‘id’ and ‘ego’). Thus, the term ‘the id’ was introduced relatively late by Freud (Freud, 1923) as a new name for ‘the unconscious’ in its systematic sense (i.e. ‘the system unconscious’ or ‘system Ucs’) (Freud, 1900, 1915 b). Freud wrote relatively less about the id than the system unconscious but the two are essentially synonymous (see Q422, Q423, Q458 and Q461). Freud’s decision to rename the system unconscious ‘the id’ was motivated by his acknowledgement that aspects of the ego are also unconscious (in the descriptive sense) and processes in the id can become conscious. The introduction of the id was useful in this respect as it resolved ambiguities relating to the descriptive meaning of ‘unconscious’. Referred to as ‘the id’, the unconscious could be understood more explicitly as a system subserving a specific mode of cognition (e.g. Q461). The characteristics of primary process thinking are clearest when contrasted against those of the secondary process: just as the characteristics of the primary process only become manifest in certain non-ordinary states, the characteristics of the secondary process only really become evident when they are lost. For example, Freud considered timelessness to be a major characteristic of the id and time perception to be a function of the ego (e.g. Q424). The notion of timelessness is difficult to comprehend from the vantage of normal waking consciousness but becomes clearer if we consider the phenomenology of states such as the temporal lobe aura: ‘Time seems endless’ (Epstein and Ervin, 1956); acute psychosis: ‘Time slowed down, much more experience could be crowded into a brief time span’ (Bowers, 1965) and the hallucinogenic drug state: ‘[Under the influence of drugs such as LSD, one has] the feeling that so much was ‘‘seen’’ that ‘‘hours’’ or ‘‘days’’ or ‘‘aeons’’ must have passed’ (Masters and Houston, 2000). Recent work involving the serotoninergic hallucinogen, psilocybin, has shown that hallucinogen-induced impairments in temporal perception are dose-dependent (Wackermann et al., 2008). Furthermore, recent formulations of the free-energy principle suggest that there is a systematic increase in temporal coherence in higher-level structures (Kiebel et al., 2009). Thus, impaired temporal perception is a property of primary process thinking that has the potential to be measured psychophysically; thus bringing previously intangible phenomena into the scientific realm. Four other qualities of primary process thinking that can be assessed empirically include the following.

  1. (i) Sensations of fear or dread, e.g. in the aura of temporal lobe epilepsy: ‘I feel afraid, as if something awful might happen’ (Williams, 1956); early psychosis: ‘Suddenly Fear, agonizing, boundless, Fear, overcame me, not the usual uneasiness of unreality, but real fear, such as one knows at the approach of danger, of calamity’ (Sechehaye, 1951); the hallucinogenic drug state: ‘I found myself all at once on the brink of panic’ (Huxley, 1954); and dreaming: ‘Fear is the most frequently occurring dream emotion’ (Bulkeley, 2009).
  2. (ii) Perceptual distortions/visual hallucinations, e.g. in the aura of temporal lobe epilepsy: ‘The surroundings feel strange and unfamiliar’ (Hansen and Brodtkorb, 2003); early psychosis: ‘It wasn’t really unreal; it was just strange, funny, different’ (Cutting and Dunne, 1989); and the hallucinogenic drug state: ‘The room and furniture were distorted, strange and terrifying’ (LSD, Cohen, 1964).
  3. (iii) Deja vu, recollective or reliving phenomena, e.g. in the aura of the temporal lobe epilepsy: ‘I went back to all that occurred in my childhood’ (Hughlings-Jackson, 1879); early psychosis: ‘My whole world seemed to cave in — I kept thinking about my birthplace and my past’ (Cutting and Dunne, 1989); and the hallucinogenic drug state: ‘I started to cry uncontrollably and nothing could have stopped it — it was like a dam giving way. At first I didn’t know what I was weeping about, but soon became aware that I was reliving childhood experiences of which I had scarcely any conscious knowledge. Until today I had remembered only fragments, but now the entire sequence reeled off as from a microfilm that was securely stored within my head’ (LSD, Cohen, 1964).
  4. (iv) Disturbance to the sense-of-self, e.g. in the aura of temporal lobe epilepsy: ‘I felt that I disappeared’ (Johanson et al., 2008); early psychosis: ‘When I look at somebody my own personality is in danger. I am undergoing a transformation and myself is beginning to disappear’ (Chapman, 1966); and the hallucinogenic drug state: ‘I felt the relaxing of the self boundaries’ (LSD, Cohen, 1964). Other characteristics of primary process thinking include a fear of losing control of ones mind, a general sense of the peculiarity of things, euphoria, grandiosity, paranoia and suspiciousness, thought-disturbances, bizarre thought-content and an increased interest in mystical, magical or animistic notions. All these phenomena could easily be assessed using subjective rating scales as a global measure of ego-disturbance or primary process thinking. However, an association between the primary process and dreaming, acute psychosis, temporal lobe aura and hallucinogenic states can be motivated at a purely phenomenological level. Crucially, all these states have been compared with each other previously; e.g. psychosis and dreaming (Freud, 1900; Jung, 1907; Bleuler, 1911); psychosis and the temporal lobe aura (Slater and Beard, 1963; Bear, 1979; Ferguson and Rayport, 2006); psychosis and the hallucinogenic drug state (Behringer, 1927; Bowers and Freedman, 1966; Gouzoulis et al., 1994); dreaming and the temporal lobe aura (Rodin et al., 1955; Penfield and Perot, 1963; Mahl et al., 1964); dreaming and the hallucinogenic drug state (Grof, 1975; Fischman, 1983; Callaway, 1988); and the temporal lobe aura and the hallucinogenic drug state (Bercel et al., 1956; Schwarz et al., 1965; Balestrieri, 1967). It is also worth noting that dreaming (Freud, 1900), psychosis (Freud, 1900; Bleuler, 1911), the temporal lobe aura (Kubie, 1952; Robin et al., 1955; Delgado et al., 1956; Epstein and Ervin, 1956; Ostow, 1957; Mahl et al., 1964; Horowtiz et al., 1968) and the hallucinogenic drug state (Busch and Johnson, 1950; Sandison et al., 1954; Cattell, 1957; Martin, 1957; Eisner, 1959; Cohen, 1964; Abramson, 1967; Horowitz et al., 1968; Grof, 1975) have all been described as states conducive to the emergence of primary process thinking. In the remainder of this section we will review evidence that these states, which clearly display a related phenomenology, also possess a related neurophysiology.

Neurophysiology of the primary process

In this section, we show that brain states associated with primary process thinking have common neurophysiological substrates. Intracranial electroencephalography (EEG) recordings in medial temporal structures, the superior temporal gyrus and the visual association cortex, after high-frequency stimulation of the perirhinal cortex, reveals bursts of synchronous high-amplitude theta activity spreading from the medial temporal lobes to the visual association cortices during the hallucinatory revival of past experiences (Barbeau et al., 2005). This activity is consistent with Freud’s speculations about the processes underlying dreaming and related states (e.g. Q97 and Q98). Similar activity has been recorded in the medial temporal lobes of other epileptic patients during states of hallucinosis and recollection (Rodin et al., 1955; Heath, 1961; Stevens et al., 1969) and increased theta power has been recorded over the medial temporal lobes during recollection using magnetoencephalography (Guderian and Dut zel, 2005). In the 1950s and early 1960s, activity was recorded in cortical and subcortical structures in a large number of patients experiencing acute psychotic episodes (Heath, 1954; Lesse et al., 1955; Sem-Jacobsen et al., 1956; Heath and Mickle, 1960; Sherwood, 1962; Heath and Walker, 1985). Subcortical contacts revealed conspicuous activities, which were generally not seen in the cortex or at the scalp (Sem-Jacobsen et al., 1956; Heath and Mickle, 1960). In actively psychotic patients, spiking and bursts of high-amplitude synchronous activity (of variable frequency but often theta) were recorded in the septum (which until the mid-1970s included the nucleus accumbens) (Heath, 1954; Stevens, 1999) amygdala and hippocampus (Sem-Jacobsen et al., 1956; Heath and Mickle, 1960; Sherwood, 1962). This activity was specific to these regions, was most pronounced when the psychosis was most florid and was absent when the symptoms remitted (Heath and Mickle, 1960). Intracranial recordings in subjects administered the hallucinogenic drugs LSD and mescaline revealed spiking and bursts of high-amplitude activity in the medial temporal lobes similar to that recorded in the acutely psychotic patients (Schwarz et al., 1956; Sem-Jacobsen et al., 1956; Monroe et al., 1957; Heath and Mickle, 1960; Chapman et al., 1962). LSD and related drugs were used extensively in the 1950s and 60s as adjuncts to psychoanalytic psychotherapy (Abramson, 1967; Grinspoon and Bakalar, 1979). Spontaneous recollections of a similar nature to those associated with the temporal lobe aura (e.g. Penfield and Perot, 1963; Barbeau et al., 2005) have been reported after ingestion of LSD and psilocybin (e.g. Sandison et al., 1954; Grof, 1975; Vollenweider et al., 1997). High-amplitude bursts of low-frequency/theta activity have also been recorded in the human hippocampus in rapid eye movement (REM) sleep (Brazier, 1968; Freemon and Walter, 1970; Giaquinto, 1973; Moiseeva and Aleksanyan, 1976; Mann et al., 1997; Y et al., 1997; Bou dizs et al., 2001; Cantero et al., 2003) and LSD given to humans immediately prior to (Toyoda, 1964; Muzio et al., 1966) or during sleep (Torda, 1968) has been shown to promote REM sleep and dreaming. These studies provide converging evidence that a specific mode of cognition (primary process thinking), rests on brain states, which possess a characteristic neurophysiology. There are also some interesting examples of medial temporal activities being influenced by psychiatric interview (Heath, 1954, 1964; Lesse et al., 1955). Sporadic bursts of high-amplitude synchronous activity recorded intracranially in the medial temporal lobes (Heath, 1954, 1964; Lesse et al., 1955) were detected as personal memories, with strong emotional content, were touched on. The activity desynchronized if the patient attended to his environment (Lesse et al., 1955) or carried out a mathematical problem (Heath, 1954, 1964). The abnormal limbic activity recorded in the temporal lobe aura, acute psychosis, the hallucinogenic drug state and REM sleep is often seen in the theta range (Sem-Jacobsen et al., 1955; Heath et al., 1955–56; Schwarz et al., 1956; Sem-Jacobsen et al., 1956; Monroe et al., 1957; Heath and Mickle, 1960; Chapman et al., 1962; Sherwood, 1962; Cantero et al., 2003; Barbeau et al., 2005), although bursts of high-amplitude fast activity were also seen (e.g. Lesse et al., 1955; Heath et al., 1955-56). Hippocampal theta in animals is reliably associated with locomotion, orienting and REM sleep (Kahana et al., 2001) and also long-term potentiation (Hot lscher et al., 1997). Hippocampal theta depends on inputs from the septal nuclei, a major theta generator (Petsche et al., 1962; Winson 1978) and another site from which the abnormal activity was recorded in non-ordinary states in humans (e.g. Heath, 1954; Sherwood, 1962). As well as providing conditions for encoding new experiences, hippocampal theta facilitates the retrieval of past experiences (Hasselmo et al., 2002 Barbeau et al., 2005). Scalp recordings of increased theta power associated with goal-directed cognition (Burgess and Gruzelier, 2000; Krause et al., 2000; Onton et al., 2005) are unlikely to relate to the high-amplitude bursts seen in the septum and medial temporal lobes during the non-ordinary states of consciousness described above (Gevins et al., 1997; Kahana et al., 2001; Buzsaki 2002; Raghavachari et al., 2006). The cortex is capable of generating its own theta (Silva et al., 1991; Raghavachari et al., 2006) and intracranial work in humans has provided more evidence for low-amplitude, high-frequency oscillations in the hippocampus during attentiveness than for theta (Heath, 1954, 1964; Lesse et al., 1955; Halgren et al., 1978; Arnolds et al., 1980; Huh et al., 1990; Meador et al., 1991; Caplan et al., 2001; Axmacher et al., 2007). Moreover, in the non-ordinary states, activity recorded from the scalp and in the cortex is generally low-amplitude, high-frequency and desynchronous (Heath and Mickle, 1960; Chapman et al., 1962; Rodin et al., 1966; Cantero et al., 2003); such activity is highly characteristic of REM sleep (Jouvet, 1965; Maquet et al., 1996; Braun et al., 1998; Cantero et al., 2003; Wehrle et al., 2007) and other cortical ‘up’ states (Steriade et al., 2001) such as those induced by serotoninergic hallucinogens (Lambe and Aghajanian, 2006). Based on empirical findings (e.g. Can) ive et al., 1996; Jeanmonod et al., 1996, 2003; Llinas et al., 1998, 1999) it has been proposed that bursts of limbic theta, recorded in the cortex as increased gamma, can index the positive symptoms of various neurological and psychiatric disorders (Llinas et al., 1999; Jeanmonod et al., 2003; Llinas and Steriade, 2006). Under normal conditions, cortical gamma readily suppresses low-frequency oscillations (Chen et al., 2009). This function is analogous to the secondary process, but in pathological states and dreaming, limbic activity is more anarchic (e.g. Oertel et al., 2007; Wehrle et al., 2007) and the cortex must work harder to contain it (Llinas et al., 1999; Jeanmonod et al., 2003; Llinas and Steriade, 2006). Recent intracranial EEG work in humans, using subdural electrodes recorded theta phase-modulation of high-frequency (80–150Hz) gamma power (Canolty et al., 2006). Theta modulation of gamma power was evident at rest but also during behavioural tasks. Theta-gamma coupling was highest at the trough of the theta phase. Moreover, electrodes showing the highest mean theta power also showed the strongest theta-gamma coupling. These findings imply that theta modulates coupling between theta and gamma and a number of researchers have suggested that theta may promote long-range coupling in cortical networks (e.g. von Stein and Sarnthein, 2000; Buzsaki, 2006).

Summary and synthesis

Integrating these findings, we propose that high-amplitude low-frequency (e.g. theta) discharges in limbic and paralimbic regions index the free-energy of the Helmholtzian scheme and mediate the primary process of the Freudian scheme. In waking cognition, low-frequency limbic oscillations couple to (i.e. entrain) gamma in the cortex (Canolty et al., 2006; Llinau s and Steriade, 2006) enabling the activity of the cortex to explain and thereby contain the activity of the limbic regions (Engel et al., 2001; Friston, 2003; Chen et al., 2009). In non-ordinary states, this function may be perturbed (e.g. in the case of hallucinogenic drugs, through actions at modulatory post-synaptic receptors) (Aghajanian and Marek, 1997), compromising the hierarchical organization and suppressive capacity of the intrinsic networks. To investigate these phenomena further, neuroimaging measures of functional and effective connectivity could be employed to assess whether e.g. phasic events in REM sleep or the hallucinogenic drug state correlate with an increased limbic input to higher-level association cortices. It might transpire that in these states, limbic discharges become capable of traversing systems, which they are unable to do under normal conditions. For example, it might be possible to observe limbic discharges influencing activity in visual association areas (see Barbeau et al., 2005). One might expect limbic activity to be suppressed by higher-level regions of the DMN in normal waking cognition but not in non-ordinary states. This might explain the difference between the experience of day-dreaming in the resting-state (Mason et al., 2007, Q284 and Q332) and hallucinosis in non-ordinary states (Q97), where limbic activity is released from top-down control. The mechanisms of this release have been discussed previously in terms of perceptual inference and synaptic gain (Friston, 2005b; Stephan et al., 2009), where the major determinant of synaptic gain is neuronal synchronization.


In this article we have explored the notion that Freud’s descriptions of the secondary process are consistent with the functional anatomy of large-scale intrinsic networks. We have proposed that intrinsic networks self-organize into hierarchical frameworks, in order to suppress the free-energy of their subordinate levels. This was associated with the function of the secondary process. We hypothesized that spontaneous fluctuations in neuronal activity in cortical nodes of the DMN function to suppress or contain otherwise anarchic and unconstrained endogenous activity in limbic and paralimbic systems, while fluctuations in subordinate networks anti-correlated with the DMN predict and counter prediction errors induced by exogenous sensory input in sensory and visceral systems. Given the nature of this synthesis, different readers will find merit in different aspects of it. For example, some readers may see value in relating inferential coding to intrinsic networks and regard this as a potentially useful perspective on functional anatomy. Others may take the formal similarity between Freudian formulations and functionalist interpretations of neuronal processes as evidence for their construct validity. For example, the remarkable overlap between Freud’s theories and modern neurobiology may engage clinicians and academics who are more familiar with (and receptive to) Freud’s work (Table 2). Developing these points of contact may help anchor Freudian concepts to measurable biological phenomena and inform psychoanalytic thinking. As has been argued previously (Kandel, 1999; Solms, 2009), this process may be important for psychoanalysis. Furthermore, given the enduring, albeit marginal, influence of psychoanalysis in psychiatry, it may benefit psychiatry if psychoanalysis is properly grounded in neuroscience. This is the agenda of the Neuro-Psychoanalysis movement ( and should assist the process of separating premises that have construct validity from those which do not. Freud’s writings contain many useful heuristics for exploring global brain function, especially in non-ordinary states of consciousness. Indeed, the Freudian model owes its origins to inferences based on unconstrained states, whereas the cognitive-behavioural approach is uncertain in this domain (Morcom and Fletcher, 2007). Science usually analyses phenomena extrospectively but in the mind-sciences especially, certain phenomena demand that we look both inwards and outwards – even if introspection entails some compromise and a confrontation with our ‘it’. Freud’s theories were conceived through a study of non-ordinary states, his schooling in neurology and a readiness to introspect. If they were built on false inference and loose philosophy, it is unlikely they would have endured in the way that they have. For those opposed to Freud, who would rather see his constructs dissolved into pure phenomenology and neurobiology, we put up little resistance (e.g. Q176). Phenomenology and neuro-biology can stand alone. The Freudian model adds a framework for an integrated understanding of psychopathological phenomena. Once the full-character of non-ordinary states and cognition are understood, this framework may dissolve naturally. The synthesis attempted in this article is intended to facilitate a more comprehensive understanding of psychological and neurobiological phenomena; addressing topics which have hitherto been considered incompatible with the cognitive paradigm (e.g. Morcom and Fletcher, 2007). The Freudian model should not impede hypothesis testing but rather facilitate it by emphasizing the importance of studying the phenomenology, neurophysiology and neurodynamics of different modes or states of cognition; and by indicating where we might look for anomalies. For example, altered functional connectivity between limbic and cortical nodes of the DMN may predict symptoms of ego-disturbance or primary process thinking. Identifying the neurobiological signature of ego-disturbance or primary process thinking may provide new insights into the pathogenesis of schizophrenia, given that related symptoms are prevalent in the prodromal phase (Maller and Husby, 2000; Parnas and Handset, 2003; Hat fner and Maurer, 2006). Another symptom cluster, which might benefit from a Freudian treatment, is the withdrawal seen in depression and schizophrenia. The association between ego–libido and object–libido and the give-and-take between the DMN and its anti-correlated networks may be especially relevant here: All that we know about [libido] relates to the ego, in which at first the whole available quota of libido is stored up. We call this state absolute, primary narcissism. It lasts till the ego begins to invest the ideas of objects with libido, to transform narcissistic libido [ego–libido] into object–libido. Throughout the whole of life the ego remains the great reservoir from which libidinal investments are sent out to objects and into which they are also once more withdrawn. (Freud, 1940; Q454) The notion of displacing energy from a default store to networks concerned with scrutinizing the external world is consistent with the functional relationship of the DMN to its anti-correlated networks, where e.g. activity is displaced from the DMN to the dorsal attention system during goal-directed cognition (Raichle et al., 2001): We see also, broadly speaking, an antithesis between ego–libido and object–libido. The more of one is employed, the more the other becomes depleted. (Freud, 1914; Q173) It is interesting that Freud’s notion of a finite ‘reservoir’ of energy and the reciprocal patterns of activation between the DMN and subordinate networks both fit comfortably with hierarchical minimization of free-energy. This minimization entails recurrent message-passing between hierarchical brain systems that try to suppress the free-energy at all levels (this scheme is also called predictive coding; e.g. Jehee and Ballard, 2009). The ensuing dynamics mean that increased neuronal activity at one level suppresses neural activity encoding prediction-error in another, leading to reciprocal patterns of activation and deactivation; see Murray et al. (2002) for a nice empirical example of this in the visual system and Friston and Stephan (2005) for a simulation in the auditory system. In brief, the ‘reservoir’ of free-energy is constantly primed by surprising or unaccountable exchanges with the sensorium and is distributed throughout the hierarchy in an attempt to minimize its expression at any one level. Recent work has shown reduced task-evoked suppressions of DMN activity in schizophrenia (Pomarol-Clotet et al., 2008; Whitfield-Gabrieli et al., 2009) the severity of which correlated positively with connectivity in the DMN (Whitfield-Gabrieli et al., 2009). These findings support the observation that there is a reduced engagement with the external world in schizophrenia (see Table 1, row 9 and especially Q168 and Q170). In this article we have proposed that the brain’s functional anatomy is organized hierarchically to ensure that free-energy is minimized in the most efficient way. Organized in this manner, the brain explains internal and external events and effectively discriminates between them. However, assuming that the development and maintenance of this organization is use-dependent, it will be jeopardized if the individual withdrawals from the external world. If the brain’s hierarchical organization begins to breakdown, there may be an ensuing confusion over, among other things, what are internal and external sensations. This may be especially relevant during puberty, when the ego is forced to negotiate new demands from internal and external sources and through this, develop an adult ego. According to our model, the development of an adult ego (a properly functional DMN) is necessary to contain internal excitations and coordinate engagements with the external world. If this is not achieved, systems normally inhibited by the DMN (e.g. the salience system) may slip from its control. In the ensuing chaos, the patient may develop delusions as a compromise strategy for containing the increase in free-energy. Thus, from the free-energy perspective, withdrawal, psychomotor poverty and delusional thinking may be last resorts for someone who finds everything surprizing and unpredictable. See Fletcher and Frith (2009) and Corlett et al. (2009) for a free-energy (predictive coding) treatment of false inference in schizophrenia. As in schizophrenia, Freud recognized that a retreat from the external world is also characteristic of depression. In depression however, emphasis was laid on a loss of an intense object-love. Freud argued that the patient reacts to this loss by targeting the aggression felt towards the lost object back upon his/her own ego: There is no difficulty in reconstructing [the] process of [melancholia]. An object-choice, an attachment of the libido to a particular person, had at one time existed; then, owing to a real slight or disappointment coming from this loved person, the object-relationship was shattered But the free libido was not displaced on to another object; it was withdrawn into the ego Thus the shadow of the object fell upon the ego and the latter could henceforth be judged by a special agency, as though it were the forsaken object One or two things may be directly inferred with regards to the preconditions and effects of a process such as this. On the one hand, a strong fixation to the loved object must have been present; on the other hand, in contradiction to this, the object-[investment] must have had little power of resistance This contradiction seems to imply that the object-choice had been effected on a narcissistic basis, so that the object-[investment], when obstacles [came] in its way, [could] regress to narcissism. (Freud, 1917b, Q267) As in schizophrenia, recent work has shown a reduced task-induced suppression of DMN activity in depression (Grimm et al., 2009; Sheline et al., 2009) and these reductions correlated positively with depression severity and ratings of hopelessness (Grimm et al., 2009). Reduced blood flow and activation in the dorsolateral prefrontal cortex and hyper-perfusion, metabolism and activity in limbic and medial prefrontal regions are also reliably associated with depression (e.g. Mayberg et al., 2005, 2007; Drevets et al., 2008). These findings support the notion of a withdrawal from the external world and a pathological self-focus in depression, consistent with the Freudian account (Table 1, row 9).

Table 2

Some points of contact between Freud’s account of the mind and empirical findings in neurobiology

  • The overlapping phenomenology of REM sleep, early and acute psychosis, the temporal lobe aura and the hallucinogenic drug state.
  • All these states have been independently compared with each other previously and described independently as conducive to primary process thinking.
  • The neurophysiology of these non-ordinary states is remarkably consistent both empirically and with Freud’s descriptions of the ‘free-flowing’ energy of the primary process.
  • LSD given immediately prior to or during sleep promotes REM sleep.
  • The overlap between Freud’s descriptions of the give-and-take relationship between ego–libido and object–libido and the give-and-take relationship between the DMN and its anti-correlated networks.
  • The concordance between Freud’s descriptions of the secondary process working to minimize free-energy and the free-energy account of the hierarchical organization of intrinsic networks working to minimize prediction errors.
  • The integrated, compound nature of the DMN and Freud’s descriptions of the integrated, compound nature of the ego.
  • The development of functional connectivity between the nodes of the DMN during ontogeny, a process that parallels the emergence of ego-functions.
  • Freud’s account of the ego as a recipient and product of regular endogenous activity concerned with drive, memory and affect and the functional and structural connectivity of the DMN’s cortical nodes with limbic structures concerned with drive, memory and affect.
  • Freud’s description of the ego as a tonic reservoir of activity and the high resting-state metabolism of the DMN.
  • Freud’s account of the ego as the seat of the sense-of-self and studies showing increased activity in the DMN during self-referential processing and a failure to deactivate the DMN in pathology characterized by withdrawal.


The first section of this article reviewed evidence that the development and functioning of the DMN and its functional relationship with its anti-correlated networks is consistent with that of the ego. In the second we described the phenomenology of primary process thinking, reviewed evidence that it can be observed in certain non-ordinary states and cited studies indicating that these states share a common neurophysiology. In the final section we sought to justify the synthesis and show how reference to the Freudian model might be used to understand clinically relevant phenomena in neurobiological terms. This article does not address the efficacy of psychoanalysis as a treatment (see Fonagy, 2003 for a relevant review and Q478). Our focus is on the validity of Freudian constructs in relation to global phenomena and related theories that have recently emerged in systems neuroscience. Finally, this synthesis was compelled by the links between psychopathology and the neurophysiology of certain non-ordinary states of consciousness, and between the functional organization of intrinsic brain networks and the secondary process as described by Freud. The synthesis is empirically-led, as are the methods we recommend for testing and applying it. The neurobiological phenomena addressed in this synthesis are central topics in contemporary neuroscience and the Freudian concepts are principal components of his model, where these components can be traced to his schooling in neurology and the influence of people like Meynert, Helmholtz, Fechner, Hering, Herbart, Charcot and Hughlings-Jackson.


We would like to thank our reviewers for very helpful guidance in presenting and extending these ideas.


KJF was funded by the Wellcome Trust. RCH is supported by the Beckley Foundation and has recently received a research grant from the Neuropsychoanalysis Association.


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Supplementary Material


Relevant writings from the Complete Psychological Works of Sigmund Freud

The quotations cited below are considered to be of general relevance and interest to the central manuscript.

Standard Edition, Volume 1. A Project for a Scientific Psychology. 1895.

  • The nervous system receives stimuli from the somatic element itself – endogenous stimuli – which equally have to be discharged. These… give rise to the major needs, hunger, respiration and sexuality. From these the organism cannot withdraw as it does from external stimuli [Q1, Freud, 1895, p. 297a].
  • The nervous system must put up with maintaining a store of [energy] sufficient to meet the demand for a specific action. Nevertheless, the manner in which it does this shows that the same trend persists, modified into an endeavour at least to keep the [energy] as low as possible and to guard against any increases of it – that is, to keep it constant. [Q2, Freud, 1895, p. 297b]
  • Thus there are permeable neurones (offering no resistance and retaining nothing), which serve for perception, and impermeable ones (loaded with resistance, and holding back [energy], which are the vehicles of memory and so probably psychical processes in general. [Q3, Freud, 1895, p. 300a]
  • We can then say: Memory is represented by the facilitations existing between the ψ neurones. [Q4, Freud, 1895, p. 300b]
  • “Here we are almost involuntarily reminded of the endeavour of the nervous system, maintained through every modification, to avoid being burdened by [energy] or to keep the burden as small as possible. Under the compulsion of the exigencies of life, the nervous system was obliged to lay up a store of [energy]. [Q5, Freud, 1895, p. 301]
  • “The system φ would be the group of neurones which the external stimuli reach, the system ψ would contain the neurones which receive the endogenous excitations. [Q6, Freud, 1895, p. 303a]
  • The system φ, which is turned towards the external world… [Q7, Freud, 1895, p. 304]
  • We discover, in fact, that the φ neurones do not terminate at the periphery freely… but in cellular structures which receive the exogenous stimulus in their stead. These ‘nerve-ending apparatuses’, in the most general sense, might well have it as their purpose not to allow exogenous [energy] to make an undiminished effect upon φ but to damp them down. [Q8, Freud, 1895, p. 306]
  • It would be possible to follow a Darwinian line of thought and to appeal to the fact of impermeable neurones being indispensable and to their surviving as a consequence. [Q9, Freud, 1895, p. 303b]
  • In that case, however, a place has to be found for the content of consciousness in our quantitative ψ processes. Consciousness gives us what are called qualities – sensations which are different in a great multiplicity of ways and whose difference is distinguished according to its relations with the external world. Within this difference there are series, similarities and so on, but there are in fact no quantities in it. It may be asked how qualities originate and where qualities originate. These are questions which call for the most careful examination and which can only be treated roughly here.
  • Where do qualities originate? No in the external world. For out there, according to the view of our natural science, to which psychology too must be subjected here, there are only masses in motion and nothing else. In the φ system perhaps? That tallies with the fact that the qualities are linked with perception, but it is contradicted by everything that rightly argues in favour of the seat of consciousness being in the upper storeys of the nervous system. In the ψ system then. Against his, however, there is weighty objection. During perception the φ and ψ systems are in operation together [one engaging while the other disengages]; but there is one psychical process which is no doubt performed exclusively in ψ – reproducing or remembering – and this, speaking generally, is without quality. Remembering beings about de norma nothing that has the peculiar character of perceptual quality. Thus we summon up courage to assume that there is a third system of neurones – ω perhaps [we might call it] – which is excited along with perception, but not along with reproduction, and whose states of excitation give rise to the various qualities – are, that is to say, conscious sensations. [Q10, Freud, 1895, p. 309a]
  • The ω neurones behave like organs of perception, and in them we could find no place for a memory.” [Q11, Freud, 1895, p. 309b]
  • The ω neurones are incapable of receiving [energy] but instead appropriate the period of the excitation and that this state of theirs of being affected by period while they are being filled the minimum of [energy] is the fundamental basis of consciousness. [Q12, Freud, 1895, p. 310]
  • The qualitative characteristics of the stimuli now proceeds unhindered through φ by way of ψ to ω. [Q13, Freud, 1895, p. 314]
  • Now there is a basic law of association by simultaneity, which operates in the case of pure ψ activity, of reproductive remembering, and which is the foundation of all links between the ψ neurones. We find that consciousness – that is, the quantitative activation of a ψ neurone, passes over to another, if the two have some time been simultaneously activated… It follows in the terms of our theory that [energy] passes more easily from an active neurone to another activate neurone than to an inactive one. [Q14, Freud, 1895, p. 319]
  • “[A]n organisation has been formed in ψ whose presence interferes with the passage [of energy]… This organisation is called the ‘ego’. It can easily be depicted if we consider that the regularly repeated reception of endogenous [activity] in certain neurones and the facilitating effect proceeding thence will produce a group of neurones which is constantly [activated] and this corresponds to the vehicle of the store required by the secondary function. Thus, the ego is to be defined as the totality of the ψ [activity], at any given time, in which a permanent component is distinguished from a changing one.” [Q15, Freud, 1895, p. 323a]
  • It is easy to see that the facilitations between the ψ neurones are a part of the ego’s possessions, as representing possibilities, if the ego is altered, for determining its extent in the next few moments. Q16, [Freud, 1895, p. 323b]
  • Let us picture the ego as a network of activated neurones well facilitated in relation to one another. [Q17, Freud, 1895, p. 323c]
  • If an ego exists, it must inhibit psychical primary processes. [Q18, Freud, 1895, p. 324]
  • It is probably the ω neurones which furnish this indication: the indication of reality. In the case of every external perception a qualitative excitation occurs in ω, which in the first instance, however, has no significance for ψ. It must be added that the ω excitation leads to ω discharge and information of this, as of every discharge, reaches ψ. The information of the discharge from ω is thus the indication of quality or reality for ψ. [Q19, Freud, 1895, p. 325]
  • Indication of quality follows, if it comes from outside, whatever the intensity of the activation, whereas if it comes from ψ, it does so only when there are large intensities. It is accordingly inhibition by the ego which makes possible a criterion for distinguishing perception and memory. Biological experience will then teach that discharge is not to be initiated till the indication of reality has arrived, and that with this in view the activation of the desired memories in not to be carried out beyond a certain amount. [Q20, Freud, 1895, p. 326a]
  • On the other hand, the excitation of the ω neurones can also serve to protect the ψ system in the second case: that is, by drawing the attention of ψ to the fact of a perception being present of absent: For this purpose it must be assumed that the ω neurones are originally linked anatomically with the paths of conduction from the various sense-organs and that they direct their discharge back to the motor apparatuses belonging to the same sense organs. In that case the information of the latter discharge (the original reflex attention) will act to ψ biologically as a signal to send out a quantity of energy in the same directions. [Q21, Freud 1895, p. 326b]
  • So then: if there is inhibition by an active ego, the indications of ω discharge become quite generally indications of reality which ψ learns, biologically, to make use of. If, when an indication of reality of the kind emerges, the ego is in a state of wishful tension, it will allow discharge towards the specific action to follow. If an increase of unpleasure coincides with the indication of reality, then ψ will, by means of [lateral connections or local inhibition] of suitable magnitude, institute a defence of normal magnitude at the point indication. [Q22, Freud, 1895, p. 326c]
  • [Wishful discharges] to the point of hallucination and complete generation of unpleasure which involves a complete expenditure of defence are described by us as psychical primary processes; by contrast, those processes which are only made possible by a good engagement of the ego, and which represent a moderation in the foregoing, and are described as psychical secondary processes. It will be seen that the necessary preconditions of the latter is a correct employment of the indications of reality, which is only possible when there is inhibition by the ego. [Q23, Freud, 1895, p. 326-327]
  • Perceptual activations are never activations of single neurones but always of complexes. [Q24, Freud, 1895, p. 327b]
  • Judging is a ψ process which is only made possible by inhibition by the ego and which is evoked by the dissimilarity between the [wishful notion] of a memory and a perceptual activation that is similar to it. It can be inferred from this that coincidence between the two cathexes becomes a biological signal for ending the act of thought… Their non-coincidence [or non-concordance] gives the impetus for the activity of thought, which is terminated once more with their coincidence [or concordance]. [Q25, Freud, 1895, p. 328]
  • Let us suppose, for instance, that the mnemic image wished for [by a child] is the image of the mother’s breast and a front view of its nipple, and that the first perception is a side view of the same object, without the nipple. In the child’s memory there is an experience, made by chance in the course of sucking, that with a particular head-movement the front image turns into the side image. The side image which is now seen leads the head-movement; and experiment shows that its counterpart must be carried out and the perception of the front view is achieved. [Q26, Freud, 1895, p. 328-329]
  • In so far as activations coincide, they give no occasion for activity of thought. On the other-hand, the non-coinciding portions ‘arouse interest’ and can give occasion for activity of thought in two ways. The current is either directed on to the aroused memories and sets an aimless activity of memory at work, which is then moved by differences not similarities, or the current remains in the components of perception which have newly emerged and in that case exhibits an equally aimless activity of judging. [Q27, Freud, 1895, p. 331a]
  • Let us suppose that the object which furnishes the perception resembles the subject – the fellow human being. If so, the theoretical interest taken it is also explained by the fact that an object like this was simultaneously the subject’s first satisfying object and further his first hostile object as well as his sole helping power. For this reason it is in relation to a fellow human-being that a human-being learns to cognize. [Q28, Freud, 1895, p. 331b]
  • Judgment, as will be seen, is not a primary function, but presupposes the activation from the ego of the disparate portions of the perception. [Q29, Freud, 1895, p. 332a]
  • The aim and end of all thought-processes is thus to bring about a state of identity, the conveying of a signal emanating from outside, into a neurone activated from the ego. [Q30, Freud, 1895, p. 332b]
  • While one is perceiving the perception, one copies the movement oneself – that is, one innervates so strongly the motor image of one’s own which is aroused towards coinciding [with the perception], that the movement is carried out. Hence one can speak of a perception having an imitation-value. Or the perception may arouse the mnemic image of a sensation of pain of one’s own, so that one feels the corresponding unpleasure and repeats the appropriate defensive movement. Here we have the sympathy-value of a perception. [Q31, Freud, 1895, p. 333]
  • The process of thought consists in the activation of ψ neurones accompanied by a change, brought about by [lateral or local connections] from the ego… The lateral connections as it were binds a quota of the energy flowing through the neurone. [Q32, Freud 1895, p. 334-335]
  • There is no doubt, however, that the process of thought does leave lasting traces behind it, since a second thinking, a rethinking, calls for so much less expenditure than a first. In order that reality shall not be falsified, therefore, special traces are needed, signs of the processes of thought, constituting a thought-memory which it is not yet possible to shape. [Q33, Freud, 1895, p. 335]
  • It is an important fact that primary processes, such as have been biologically suppressed in the course of ψ development, are daily presented to us during sleep. [Q34, Freud, 1895, p, 336]
  • Accordingly, the precondition for sleep is a lowering of the endogenous load in the ψ nucleus, which makes the secondary process superfluous. In sleep an individual is in an ideal state of inertia, rid of his store of [energy]. In adults, this store is collected in the ‘ego’; we may assume that it is the unloading of the ego which determines and characterises sleep. And here, as is immediately clear, we have the precondition of psychical primary process. [Q35, Freud, 1895, p. 336]
  • Nothing disturbs sleep more than the emergence of sense-impressions, activations entering ψ from φ. [Q36, Freud, 1895, p. 337]
  • If the ego were completely unloaded sleep would be necessarily dreamless. [Q37, Freud, 1895, p. 339]
  • It is interesting furthermore that consciousness in dreams furnishes quality with as little trouble as in waking life. This shows that consciousness does not cling to the ego but can become an addition to any ψ processes. It warns us, too, against possibly identifying primary processes with unconscious ones. Here are invaluable hints for the future! [Q38, Freud, 1895, p. 340]
  • It must be possible for what I have termed the secondary processes to be explained on mechanical lines through the effect produced by a constantly [activate] mass of neurones (the ego) on others with changing [levels of activity]… If I have on the one hand the ego and on the other hand perceptions – that is, activations in ψ coming from φ (from the external world) – then I require a mechanism which causes the ego to follow the perceptions and to influence them. I find it in the fact that, according to my presuppositions, a perception invariably excites ω and thus gives rise to indications of quality. To put it more accurately. It excites consciousness (consciousness of a quality) in ω, and the discharge of the ω excitation will, like every discharge, furnish information to ψ, which is in fact the indication of quality. I therefore put forward the suggestion that it is indications of quality which interest ψ in the perception. This would seem to be the mechanism of psychical attention [Q39, Freud, 1895, p. 360]
  • Attention thus consists in establishing the psychical state of expectation… Attention is biologically justified; it is only a question of guiding the ego as to which expectant activation it is to establish and this purpose is served by the indications of quality. [Q40, Freud, 1895, p. 361]
  • [Speech association] consists in the linking of ψ neurones with neurones which serve sound presentations and themselves have the closest association with motor-speech images. These associations have an advantage of two characteristics over others: they are limited (few in number) and exclusive. In any case, from the sound-image the excitation reaches the word-image and from it reaches discharge. Thus, if the mnemic-images are of such kind that a part-current can go from them to the sound-images and motor-images, then the activation of the mnemic-images is accompanied by information of discharge, which is an indication of quality and also accordingly as indication of the consciousness of the memory. If now the ego preactivates these word-images as it earlier did the images of ω discharge, then it will have created for itself the mechanism which directs the ψ activation to the memories emerging during the passage of energy. This is conscious observing thought. [Q41, Freud, 1895, p. 365]
  • The indications of speech discharge… put thought processes on a level with perceptual processes, lend them reality and make memory of them possible. [Q42, Freud, 1895, p. 366a]
  • Speech-innervation is originally a path of discharge for ψ, operating like a safety-valve, for regulating oscillations in energy; it is a portion of the path to internal change, which represents the only discharge till the specific action has been found. This path acquires a secondary function from the fact that it draws the attention of the helpful person (usually the wished-for object itself) to the child’s longing and distressful state; and thereafter it serves for communication and is thus drawn into specific action. [Q43, Freud, 1895, p. 366b]
  • In virtue of the trend towards imitation, which emerges during judging, it is possible to find the information of movement attaching to this sound-image. This class of memories, too, can now become conscious. It now still remains to associate intentional sounds with the perceptions; after that, the memories when the indications of sound discharge are observed become conscious like perceptions and can be activated from ψ. Thus we have found that it is characteristic of the process of cognitive thought that during it attention is from the first directed to the indications of thought-discharge, to the indications of speech. As is well known, indeed, what is called conscious thought takes place to the accompaniment of slight motor expenditure… [and] if thought is intense… people even speak out loud. [Q44, Freud, 1895, p. 367]
  • The secondary process is characterised by a bound state in the neurone, which though there is a high cathexis, permits only a small current… Now the ego itself is a mass like this of neurones which hold fast to their activity – are, that is in a bound state and this surely can only happen as a result of the effect they have on one another. We can therefore imagine that a perceptual neurone which is active with attention is as a result temporarily, as it were, taken up into the ego and is now subject to the same binding of its energy as are all the other ego neurones… This bound state, which combines high activity with small current, would thus characterise processes of thought mechanically. [Q45, Freud 1895, p. 368]
  • Thus we find ourselves quite unexpectedly before the most obscure problem; the origin of the ego – that is, of a complex of neurones which hold fast to their activity, a complex, therefore, which is for short periods at a constant level… The ego consists originally of the nuclear neurones, which receive endogenous energy though paths of conduction. [Q46, Freud, 1895, p. 369a]
  • The education and development of this original ego take place in a state of craving, in expectation. It learns first that it must not activate motor-images so that discharge results until certain conditions have been fulfilled from the direction of perception. It learns further that it must not activate the wishful idea beyond a certain amount since otherwise it would deceive itself in a hallucinatory manner. If however, it respects these two barriers and directs its attention to the new perceptions, it has a prospect of attaining the satisfaction it is seeking. It is clear, therefore, that the barriers which prevent the ego from activating the wishful-image and the motor-image beyond a certain amount are the ground for the accumulation of energy in the ego and compel it perhaps to transfer its energy within certain limits to the neurones accessible to it. [Q47, Freud, 1895, p. 369b]
  • The whole activated mass is in equilibrium, held on one side by the two barriers against motility and wishing and on the other side by the resistances of the furthest neurones and towards the interior by the constant pressure of the path of conduction. Inside this ego-structure the activation will by no means be everywhere equal; it need only be equal proportionately – that is, in relation to the facilitations [i.e., connections]. [Q48, Freud, 1895, p. 370a]
  • All we can say is that when this barrier was not yet in existence and when motor discharge took place along with the wish, the expected pleasure regularly failed to appear and the continuance of the release of endogenous stimuli finally evoked unpleasure. Only this threat of unpleasure, which came because became attached to premature discharge, can represent the barrier in `question. [Q49, Freud, 1895, p. 370b]
  • Unpleasure remains the only means of education. [Q50, Freud, 1895, 370c]
  • For the ego then, the biological rule of attention runs: If an indication of reality appears, then the perceptual activation which is simultaneously present is to be hyperactivated. [Q51, Freud, 1895, p. 371]
  • It follows from the description of the ego and of its oscillations that the height of the level of its activation too, has no relation to the external world, that a general lowering or raising of it makes no change (normally) in the picture of the world. Since the picture of the world is based on facilitations [i.e., connections] that means that general oscillations of level make no change in the facilitations. A second principle has already been mentioned: namely, that when the level of activity is high, small quantities can be displaced more easily than when it is low. [Q52, Freud, 1895, 372a]
  • Let us go back now to the description of the observing or cognitive process of thought, which is distinguished from the process of expectation by the fact that [in the former] the perceptions do not light upon wishful activations. Thus, in that case the ego is made attentive by the first indications of reality as to which region of perception is to be activated. The passage of association of the energy brought along with them occurs over preactivated neurones and the energy which is displacing itself, can flow on again each time. During this passage of association the indications of quality (of speech) are generated, as a result of which the passage of association becomes conscious and capable of being reproduced. [Q53, Freud, 1895, p. 372b]
  • Indications of discharge through speech are also in a certain sense indications of reality – but of thought-reality not external reality, and in their case a rule of this kind has not by any means come into effect, because no constant threat of unpleasure would be attached to a breach of it. The unpleasure through neglecting cognition is not so glaring as that from ignoring the external world, though at bottom they are one and the same. Thus, there is in fact also an observing process of thought in which indications of quality are either not, or only sporadically, aroused and which is made possible by the fact that the ego follows the passage of association automatically with its activity. This process of thought is in fact far the more frequent, without being abnormal, it is our ordinary thought, unconscious, with occasional intrusions into consciousness – what is known as consciousness thought with unconscious intermediate links, though these can be made conscious. [Q54, Freud, 1895, p. 373]
  • Thought accompanied by an activation of the indications of thought-reality or of the indications of speech is the highest, securest from of cognitive thought process. [Q55, Freud, 1895, p. 374]
  • From this we arrive at a fresh thesis for the mechanical representation of psychical processes: namely, that the passage of association which is not altered by the height of the level of activity [i.e., the amplitude] can be influenced by the energy itself that is in flow. In general, a large [flow of energy] takes different pathways in the network of facilitations than a small one… The arousing of indications of thought seems then to be linked to the passage of small amounts of energy. This is not to assert that any other passage of energy is bound to remain unconscious, since the arousing of indications of speech is not the only method of arousing consciousness. [Q56, Freud, 1895, p. 375]
  • How then can we perhaps give a clear picture of thought that becomes conscious intermittently, of sudden intrusions into consciousness? After all, our ordinary purposeless thought, though it is accompanied by preactivation and automatic attention, attached no importance to indications of thought. It has not been shown biologically that they are indispensable for this process. Nevertheless, they usually emerge (1) if the smooth passage of energy has reached an end or has come up again an obstacle and (2) if it has aroused an idea which, for other reasons, calls up indications of quality – that is, consciousness. At this point the discussion can be broken off. [Q57, Freud, 1895, p. 375-376]
  • The fact that a memory exhibits a hallucinatory characteristic for so long also calls for an explanation – important for our view of hallucination. Here it is plausible to suppose that this capacity for hallucination, as well as the capacity for affect, are indications of the fact that the ego-activation has not yet gained any influence on the memory, that the primary lines of discharge and the full or primary process predominate it. We are obliged to see in the state of hallucinosis a backward flow of energy to φ and to ω, thus a bound neurone does not admit of such a backward flow. [Q58, Freud, 1895, p. 381]
  • Another ground for error may lie in the fact that the perceptions of reality have not been completely perceived because they were not within the range of the senses. These are errors of ignorance which no human being can avoid. Where this determinant does not apply , the psychical preactivation may be defective (owing to the ego being deflected away from perceptions) and inaccurate perceptions and incomplete passages of thought may result. These are errors due to insufficient attention. [Q59, Freud, 1895, p. 384]
  • The ψ processes would in themselves be unconscious and would only subsequently acquire a secondary, artificial consciousness through being linked with processes of discharge and perception (speech association). [Q60, Freud, 1896, p. 389]

Standard Edition, Volume 2. Studies on Hysteria. 1893.


  • Hysterics suffer mainly from reminiscences. [Q61, Freud & Breuer, 1893, p. 7]
  • It appears, that is to say, that these memories correspond to traumas that have not been sufficiently abreacted. [Q62, Breuer & Freud, 1893, p. 10]
  • Throughout the entire illness her two states of consciousness persisted side by side: the primary one in which she was quite normal psychically, and the secondary one which may well be likened to a dream in view of the wealth of imaginative products and hallucinations, its… lack of inhibition and control in its associations. [Q63, Breuer & Freud, 1893, p.45a]
  • Every one of her hypnoses in the evening afforded evidence that the patients was entirely clear headed and well-ordered in her mind and normal as regards her feeling and volition so long as none of the products of her secondary state was acting as a stimulus in the unconscious. The extremely marked psychosis which appeared whenever there was any considerable interval in this unburdening process showed the degree to which those products influenced the psychical events of her ‘normal state’. It is hard to avoid expressing the situation by saying that the patient was split into two personalities. [Q64, Breuer & Freud, 1893, p. 45b]
  • [A]nything which powerfully recalled any of her traumas brought her into a state of delirium. In such states – and the few observations I made led me to no other conclusion – there was a limitation of consciousness and a compulsion to associate similar to that prevailing in dreams; hallucinations and illusions were facilitated to the highest degree and … even nonsensical inferences were made. This state… might be regarded as an acute psychosis (serving as the equivalent of an attack) which could be classified as a condition of ‘hallucinatory confusion’. [Q65, Breuer & Freud, 1893, p. 96]
  • The actual traumatic moment, then, is the one at which the incompatibility forces itself upon the ego and at which the latter decides on the repudiation of the incompatible idea. That idea is not annihilated by a repudiation of the kind but merely repressed into the unconscious. When this process occurs for the first time there comes into being a nucleus and centre of crystallisation for the formation of a psychical group divorced from the ego. [Q66, Breuer & Freud, 1893, p. 123a]
  • If the perceptual organ is excited by a mnemic image, we must suppose that that organ’s excitability has been changed in an abnormal direction, and that this change is what makes hallucination possible. [Q66b, Breuer & Freud, 1893, p. 189]
  • How has it come about that we speak of someone who has been slighted as having been “stabbed in the heart”? All these sensations and innervations belong to the field of “The Expression of the Emotions’, which, as Darwin taught us , consists of actions which originally had an action and purpose. These may now for the most part have become so much weakened that the expression of them in words seems to us only to be a figurative picture of them, whereas in all probability the description was once meant literally. [Q67, Breuer & Freud, 1893, p. 181]
  • Let us imagine a man in a state of intense expectation, which is not, however, directed to any particular sensory field. We then have before us a brain which is quiescent but prepared for action. We may rightly suppose that in such a brain all paths of conduction are at maximum of their conductive capability – that they are in a state of tonic excitation. It is significant fact that in ordinary language we speak of such a state as one of tension. [Q68, Breuer & Freud, 1893, p. 194-5]
  • And here for the first time we meet the fact that there exists in the organism a tendency to keep intracerbral excitation constant. [Q69, Breuer & Freud, 1893, p. 197]
  • We have spoken of a tendency on the part of the organism to keep tonic cerebral excitation constant. [Q70, Breuer & Freud, 1893, p. 198]
  • The affect of anxiety entered into her reverie and created a hypnoid state… This was repeated on different occasions and the ideational content gradually became richer and richer. [Q71, Breuer & Freud, 1893, p. 235]
  • It is true that ‘unconscious ideas’ never, or only rarely and with difficulty, enter waking thought; but they influence it. They do so, first, through their consequences – when, for instance, a patient is tormented by a hallucination… So particular groups of ideas constantly force themselves on the patient with a certain amount of compulsion and he is obliged to think of them. [Q72, Breuer & Freud, 1893, p. 237]
  • Any event that provokes unconscious memories liberates the whole affective force of these ideas that have not undergone a wearing away, and the affect that is called up is then quite out of proportion to any that would have arisen in the conscious mind alone. [Q73, Breuer & Freud, 1893, p. 238a]
  • While she was in this state her waking thought was without energy, her judgment was childish and she seemed, as I have said positively imbecile. I believe that this was due to the fact that waking thought has less energy at its disposal if a great amount of psychical excitation is appropriated by the unconscious. [Q73b, Breuer & Freud, 1893, p. 238b]

Standard Edition, Volume 3. Early Psychoanalytic Publications. 1893.


  • Something in his nervous system which we will for the moment call the sum of excitation is increased. Now in every individual there exists a tendency to diminish this sum of excitation once more, in order to preserve his health. [Q74, Freud, 1893b, p.36a]
  • Psychical trauma is linked with an increase in the sum of excitation in his nervous system. [Q75, Freud, 1893b, p. 36b]
  • The man who first flung a word of abuse at his enemy instead of a spear was the founder of civilisation. [Q76, Freud, 1893b, p. 36c]
  • If someone with a disposition to neurosis lacks the aptitude for conversion [to hysteria], but if, nevertheless, in order to fend off an incompatible idea, he sets about separating it from its affects, then that affect is obliged to remain in the psychical sphere. The idea now weakened, is still left in consciousness, separated from all association. But its affect, which has become free, attaches itself to other ideas which are not in themselves incompatible; and thanks to this ‘false connection’, those ideas turn into obsessional ideas. [Q77, Freud, 1893b, p.52]
  • Here, the ego rejects the incompatible idea together with its affect and behaves as if the idea had never occurred to the ego at all. But from the moment at which this has been successfully done the subject is in a psychosis, which can only be classified as ‘hallucinatory confusion’. [Q78, Freud, 1893b, p. 58]
  • I refer to the concept that in mental functions something is to be distinguished – a quota of affect or sum of excitation – which possesses all the characteristics of a quantity (though we have no means of measuring it) which is capable of increase, diminution, displacement and discharge and which is spread over the memory-traces of ideas somewhat as an electric charge is spread over the surface of the body. This hypothesis… can be applied in the same sense as physicists apply the hypothesis of a flow of electric fluid. It is provisionally justified by its utility in co-ordinating and explaining a great variety of psychical states. [Q79, Freud, 1893b, p. 60-61]
  • The affect is a state which passes rapidly, the neurosis is a chronic one; because, while exogenous excitation operates with a single impact, the endogenous excitation operates as a constant force. In neurosis, the nervous system is reacting against a source of excitation which is internal, whereas in the corresponding affect it is reacting against an analogous source of excitation which is external. [Q80, Freud, 1895b, p. 112]
  • The action of heredity is comparable to that of a multiplier in an electric circuit, which exaggerates the visible deviation of the needle, but which cannot determine its direction. [Q81, Freud, 1896, p. 147]
  • It looks as though the difficulty of disposing of a present impression, the impossibility of transforming it into a powerless memory, is attached precisely to the character of the psychical unconscious. [Q82, Freud, 1896b, p. 219]
  • If we put the hysteric under hypnosis and lead his thoughts back to the time at which the symptom in question first appeared, memory of a psychical trauma (or series of traumas) belonging to that time awakens in him with hallucinatory vividness, the symptom having persisted as a mnemic symbol of the trauma. Thus hysterics suffer mainly from reminiscences. [Q83, Freud, 1893c, p. 244]
  • It seems that in man the sexual instinctual forces are meant to be stored up so that on their release at puberty they may serve great cultural end. [Q84, Freud, 1898, p. 281]
  • What is recorded as a mnemic image is not the relevant experience itself – in this respect the resistance gets its way; what is recorded is another psychical element closely associated with the objectionable one. [Q85, Freud, 1899, 307]
  • Close investigation shows rather that these falsifications of memory are tendentious – that is, that they serve the purposes of the repression and replacement of the objectionable or disagreeable impressions. [Q86, Freud, 1899, p. 322]

Penguin, Volume 4. The Interpretation of Dreams. 1900. Covers volumes 4 & 5 of Standard Edition.

  • Thomayer (1896) draws attention to certain anxiety dreams which he thinks should be regarded as equivalents of epileptic fits. [Q87, Freud, 1900, p. 161]
  • Krauss (1859) declares that ‘insanity is a dream dreamt while the senses are awake’. [Q88, Freud, 1900, p. 162a]
  • Schopenhauer (1862) calls dreams a brief madness and madness a long dream. [Q89, Freud, 1900, p. 162b]
  • The rapid sequence of ideas in dreams is paralleled by the flight of ideas in psychoses. In both there is a complete lack of sense of time. [Q90, Freud, 1900, p. 164]
  • We may therefore suppose that dreams are given their shape in individual human beings by the operation of two psychical forces (or we may describe them as currents or systems). [Q91, Freud, 1900, p. 225]
  • The psychical process which we have found at work in dream-displacement, though it cannot be described as a pathological disturbance, nevertheless differs from the normal and is to be regarded as a process of a more primary nature. [Q92, Freud, 1900, p. 264]
  • Our attention is thus drawn to the fact that in considering the suppressed and suppressing agencies, we must not regard their relation as being exclusively one of mutual inhibition. Just as much regard must be paid to cases in which the two agencies being about a pathological effect by working side by side and by intensifying each other. [Q93, Freud, 1900, p. 618]
  • The mind endeavours to carry upon these incoherent trains of hallucinations the same work of logical co-ordination that it carries out upon sensations during the day-time. It connects up all these detached images by an imaginary link and stops up any excessively wide gaps between them. [Q94, Freud, 1900, p. 644]
  • We describe the system that lies behind [the ego] as ‘the unconscious’. Because it has no access to consciousness except via [the ego]. [Q95, Freud, 1900, p. 690-691a]
  • We shall take the unconscious system as the starting point of dream formation. Like other thought structures, this dream instigator will make an effort to advance into [the ego] and from there to obtain consciousness. [Q96, Freud, 1900, p.691b]
  • The only way we can describe what happens in hallucinatory dreams is by saying that the excitation moves in a backward Instead of being transmitted towards the motor end of the apparatus it moves towards the sensory end and finally reaches the perceptual system. If we describe as ‘progressive’ the direction taken by psychical processes arising from the unconscious during waking life, then we may speak of dreams as having a ‘regressive’ character. This regression, then, is undoubtedly one of the psychological characteristics of the process of dreaming; but we must remember that it does not occur only in dreams. Intentional recollection and other constituent processes of our normal thinking involve a retrogressive movement in the psychical apparatus from a complex ideational act back to the raw material of the memory traces underlying it. In the waking state, however, this backward movement never extends beyond the mnemic images; it does not succeed in producing a hallucinatory revival of the perceptual images. [Q97, Freud, 1900, p. 692]
  • We call it regression when in a dream an idea is turned back into the sensory image from which it was originally derived. [Q98, Freud, 1900, p. 693]
  • In explaining regression in dreams, however, we must bear in mind the regressions which also occur in pathological waking states. My explanation of hallucinations in hysteria and paranoia and of visions in mentally normal subjects is that they are in fact regressions – that is, thoughts transformed into images. [Q99, Freud, 1900, p. 693]
  • Three kinds of regression are to be distinguished: (a) topographical regression, in the sense of the schematic picture of the ψ-systems which we have explained above; (b) temporal regression, in so far as what is in question is harking back to older psychical structures; and (c) formal regression, where primitive methods of expression and representation take the place of the usual ones. All these kinds of regression are however, one at bottom and occur together as a rule; for what is older in time is also more primitive in form and in psychical topography lies nearer to the perceptual end. [Q100, Freud, 1900, p. 699]
  • Dreaming is on the whole an example of regression to the dreamer’s earliest conditions, a revival of his childhood, of the instinctual impulses which dominated it and of the methods of expression which were available to him. Behind this childhood of the individual we are promised a picture of a phylogenetic childhood – a picture of the development of the human race. [Q101, Freud, 1900, p. 699b]
  • Psycho-analysis may claim a high place among the sciences which are concerned with the reconstruction of the earliest and most obscure periods of the beginnings of the human race. [Q102, Freud, 1900, p. 700]
  • Dreams which fulfil their wishes along the short path of regression have merely preserved for us in that respect a sample of the psychical apparatus’s primary method of working, a method which was abandoned as being inefficient. What once dominated waking life while the mind was still young and incompetent seems now to have been banished into the night – just as the primitive weapons, the bows and arrows that have been abandoned by adult men, turn up once more in the nursery. Dreaming is a piece of infantile mental life that has been superseded. [Q103, Freud, 1900, p. 721]
  • If such thing as a system Ucs [i.e., unconscious] exists… dreams cannot be its only manifestation. [Q104, Freud, 1900, p. 723]
  • Indeed it is a prominent feature of the unconscious processes that they are indestructible. In the unconscious nothing can be brought to an end, nothing is past and forgotten. [Q105, Freud, 1900, p. 733]
  • What performs this work is the [ego] and psychotherapy can pursue no other course than to bring the Ucs under the domination of the [ego]. [Q106, Freud, 100, p. 934]
  • Dreaming has taken on the task of bringing back under the control of the [ego] the excitation in the Ucs which has been left free; in so doing, it discharges the Ucs excitation, serves it as a safety valve. [Q107, Freud, 1900, p. 735]
  • If, therefore, the activation from the ego ceases, the danger is that the unconscious excitations may release affect of a kind which (as a result of the repression which has already occurred) can only be experienced as unpleasure, as anxiety. [Q108, Freud, 1900, p. 739]
  • The activity of the second system [the ego], constantly feeling its way and alternately sending our and withdrawing [energy]. Need on the one hand to have the whole of the material of memory freely at its command; but on the other hand it would be an unnecessary expenditure of energy if it sent out large quantities of energy along the various paths of thought and thus caused them to drain away to no useful purpose and diminish the quality available for altering the external world. I therefore postulate that for the sake of efficiency the second system succeeds in retaining the major part of the energy in a state of quiescence and in employing only a small part on displacement. The mechanisms of these processes are quite unknown to me; anyone who wished to take these ideas seriously would have to look for physical analogies to them and find a means of picturing the movements that accompany excitations of neurones. All that I insist upon in the idea that the activity of the first ψ-system [the id] is directed towards securing the free discharge of the quantities of excitation, while the second system [the ego] by means of the projections emanating from it, succeeds in inhibiting the discharge and in transforming the energy into a quiescent one, no doubt with a simultaneous raising of its level. [Q109, Freud, 1900, p. 758-759]
  • The regular avoidance by the psychical process of the memory of anything that had once been distressing affords us the prototype and first example of psychical repression. It is a familiar fact that much of this avoidance of what is distressing – this ostrich policy – is still to be seen in the normal mental life of adults. [Q110, Freud, 1900, p. 760]
  • The [ego] can only activate an idea if it in a position to inhibit any development of unpleasure that may proceed from it. [Q111, Freud, 1900, p. 761]
  • I propose to describe the psychical process of which the first system [the id] alone admits as the primary process; and the process which results from the inhibition imposed by the second system [the ego] as the secondary process. [Q112, Freud, 1900, p. 761b]
  • When I described one of the psychical processes occurring in the mental apparatus as the primary one, what I had in mind was not merely considerations of relative importance and efficiency; I intended also to choose a name which would give an indication of its chronological priority. It is true that so far as we know, no psychical apparatus exists which possesses a primary process only and that such an apparatus is to that extent theoretical fiction. But this much is a fact: the primary processes are present in the mental apparatus from the first, while it is only during the course of life that the secondary processes unfold and come to inhibit and overlay the primary ones; it may even be that their complete domination is not attained until the prime of life. In consequence of the belated appearance of the secondary processes, the core of our being, consisting of unconscious wishful impulses, remains inaccessible to the understanding and inhibition of the [ego], the part played by the latter is restricted once and for all to directing along the most expedient paths the wishful impulses than arise from the unconscious. [Q113, Freud, 1900. p. 763]
  • The increase in activity which becomes necessary when these primary modes of functioning are inhibited is to be found in the fact that we produce a comic effect, that is, a surplus of energy which has to be discharged in laughter, if we allow these modes of thinking to force their way through into consciousness. [Q114, Freud, 1900, p. 766]
  • The interpretation of dreams in the royal road to a knowledge of the unconscious activities of the mind. [Q115, Freud, 1900, p. 769]
  • I hope to be able to show elsewhere how the compounding of the apparatus out of two agencies makes it possible for the normal mind too to function with greater delicacy than would be possible with only one of them. [Q116, Freud, 1900, p. 769]
  • I consider it expedient and justifiable to continue to make use of the figurative image of the two systems. We can avoid any possible abuse of this method of presentation by recollecting that ideas, thoughts and the psychical structures in general must never be localised in organic elements of the nervous system but rather, as one might say, between them, where resistances and facilitations provide the corresponding correlates. [Q117, Freud, 1900, p. 771]
  • The problem of the unconscious in psychology is, in the forcible words of Lipps (1897), less a psychological problem than the problem of psychology. [Q118, Freud, 1900, p. 772]
  • The unconscious must be assumed to be the general basis of psychical life. The unconscious is the larger sphere, which includes within it the smaller sphere of the conscious. Everything conscious had an unconscious preliminary stage; whereas what is unconscious may remain at that stage and nevertheless claim to be regarded as having the full value of a psychical process. The unconscious is the true psychical reality; in its innermost nature it is as much unknown to us as the reality of the external world, and it is as incompletely presented by the data of consciousness as is the external world by the communication of our sense organs. [Q119, Freud, 1900, p. 773]


  • We have described the relations of the two systems to each other and to consciousness by saying that the [ego] stands like a screen between the [id] and consciousness. [Q120, Freud, 1900, p. 776]

Standard Edition, Volume 6. The Psychopathology of Everyday Life. 1901.


  • It may be surmised that the architectonic principle of the mental apparatus lies in a stratification – a building up of superimposed agencies. [Q121, Freud, 1901, p. 147]
  • It is in my view wrong to call the feeling of having experienced something before an illusion. It is rather that at such moments something is really touched on which we have already experienced once before, only we cannot consciously remember it because it has never been conscious. To put it briefly, the feeling of déjà vu corresponds to the recollection of an unconscious fantasy. There exist unconscious fantasies (or day-dreams) just as there exist conscious creations of the same kind which everybody knows from his own experience. [Q122, Freud, 1901, p. 266]
  • The unconscious is quite timeless. [Q123, Freud, 1901, p. 275]

Standard Edition, Volume 7. A Case of Hysteria, Three Essays on Sexuality. 1901-1905.


  • Ontogenesis may be regarded as a recapitulation of phylogenesis [Q124, Freud, 1905, p. 131]
  • By an “drive” is provisionally to be understood the psychical representative of an endosomatic, continuously flowing source of stimulation as contrasted with stimulus, which is set up by single excitations coming from without. [Q125, Freud, 1905, p. 168]
  • It is noticeable that writers who concern themselves with explaining the characteristics and reactions of the adult have devoted much more attention to the primeval period which is comprised in the life of the individual’s ancestors – have, that is, ascribed much more influence to heredity – than to the other primeval period, which falls within the lifetime of the individual himself – that is, to childhood. One would have supposed that the influence of the this latter period would be easier to understand and could claim to be considered before that of heredity. [Q126, Freud, 1905, p. 173]
  • It is during this period of total or only partial latency that are built up the mental forces which are later to impede the course of the sexual instinct and, like dams, restrict its flow – disgust, feelings of shame and the claims of aesthetics and moral ideals. One gets an impression from civilised children that the construction of these dams is a product of education and no doubt education has much to do with it. But in reality this development is organically determined and fixed by heredity. [Q127, Freud, 1905, p. 177]
  • We have defined the concept of libido as a quantitatively variable force… We this, reach the idea of a quantity of libido, to the mental representation of which we give the name ‘ego-libido’, and whose production, increase or diminution, distribution and displacement should afford us possibilities for explaining the psychosexual phenomena observed. [Q128, Freud, 1905, p. 217]
  • Narcissistic or ego-libido seems to be the great reservoir from which the object-activations are sent out and into which they are withdrawn once more; the narcissistic libidinal activation of the ego is the original state of things, realised in earliest childhood and is merely covered by the later extrusions of libido but in essential persists in them. [Q129, Freud, 1905, p. 128]

Standard Edition, Volume 8. Jokes and their Relation to the Unconscious. 1905.


  • The hearer of the joke laughs with the quota of psychical energy which has become free through the lifting of the inhibitory activation; we might say that he laughs this quota off. [Q130, Freud, 1905, p. 149]
  • For the euphoria we endeavour to reach by these means is nothing other than the mood of a period of life in which we were accustomed to deal with our psychical work in general with a small expenditure of energy – the mood of our childhood, when we were ignorant of the comic, when we were incapable of jokes and when we had no need of humour to make us feel happy in our life. [Q131, Freud, 1905, p. 236]

Standard Edition, Volume 9. Jensen’s ‘Gradiva’ and Other Works. 1906-1908.


  • ‘Repressed’ is a dynamic expression, which takes account of the interplay of mental forces; it implies that there is a force present which is seeking to bring about all kinds of psychical effects, including that of becoming conscious. The mark of something repressed is precisely that in spite of its intensity it is unable to enter consciousness. [Q132, Freud, 1907, p. 48]
  • Science does not as yet suspect the importance of repression, it does not recognise that in order to explain the world of psychopathological phenomena the unconscious is absolutely essential. [Q133, Freud, 1907, p. 53]
  • For during sleep, along with a general lowering of mental activity, there is a relaxation in the strength of the resistance with which the dominant psychical forces oppose what is repressed. It is this relaxation that makes the formation of dreams possible, and that is why dreams give us our best access to a knowledge of the unconscious part of the mind. [Q134, Freud, 1907b, p. 62-65]
  • A deeper insight into the mechanism of obsessional neurosis is gained if we take into account the primary fact which lies at the bottom of it. This is always the repression of an instinctual impulse… The influence of the repressed impulse is felt as a temptation and during the process of repression itself anxiety is generated, which gains control over the future in the form of expectant anxiety. The process of repression which leads to obsessional neurosis must be considered as one which only partly successful and which increasingly threatens to fail. It may this be compared to an unending conflict; fresh psychical efforts are continually required to counterbalance the forward pressure of the impulse. [Q135, Freud, 1907b, p. 124]

Standard Edition, Volume 10. Two Case Histories: ‘Little Hans’ and the ‘Rat Man’. 1909.


  • I then made some short observation upon the psychological differences between the conscious and the unconscious, and upon the fact that everything conscious was subject to the process of wearing-away, while what was unconscious was relatively unchangeable. [Q136, Freud, 1909, p. 176]
  • He has said to himself, he went on, that a self-reproach could only arise from a breach of a person’s own inner moral principles and not from that of any external ones. I agreed, and said that the man who merely breaks an external law often regards himself as a hero. Such an occurrence, he continued, was thus only possible where disintegration of the personality was already present. Was there a possibility of his effecting a re-integration of his personality? …The moral self was the conscious, the evil self was the unconscious. He then said that, though he considered himself a moral person, he could quite definitely remember having done things in his childhood which came from his other self. I remarked that here he had incidentally hit upon one of the chief characteristics of the unconscious, namely its relation to the infantile. The unconscious, I explained, was the infantile; it was that part of the self which had become separated off from it in infancy, which had not shared the later stages of its development, and which had in consequence become repressed. It was the derivatives of this repressed unconscious that were responsible for the involuntary thoughts which constituted his illness. [Q137, Freud, 1909, p. 177-178]
  • The chronic coexistence of love and hatred, both directed towards the same person and both of the highest degree of intensity, cannot fail to astonish us… The necessary condition for the occurrence of such a strange state of affairs in a person’s erotic life appears to be that at a very early age, somewhere in the prehistoric period of his infancy, the two opposites should have been split apart and one of them, usually hatred, have been repressed. If we consider a number of analyses of obsessional neurotics we shall find it impossible to escape the impression that a relation between love and hatred such as we have found in our present patient is among the most frequent, the most marked, and probably, therefore, the most important characteristics of obsessional neurosis. [Q138, Freud, 1909, p. 239]


Standard Edition, Volume 11. Five Lectures on Psycho-Analysis, Leonardo Da Vinci and Other Works. 1910.


  • The explanation of this fact would be a most awkward business, were ti not that the way is pointed by experiences and experiments in hypnotism. The study of hypnotic phenomena has accustomed us to what was at first a bewildering realisation that in one and the same individual there can be several mental groupings, which can remain more or less independent of one another, which can know nothing of one another and which can alternate with one another on their hold on consciousness. [Q139, Freud, 1910, p. 19]
  • You will also learn with astonishment from the analysis of dreams (and most convincingly from your own) what an unsuspectedly great part is played in human development by impressions and experiences of early childhood. [Q140, Freud, 1910, p. 36]
  • Anxiety is one of the ego’s reactions in repudiation of repressed wishes. [Q141, Freud, 1910, p. 37]
  • We have become aware in our opponents, just as we do in our patients, that their power of judgement is very noticeably influenced affectively… The arrogance of consciousness (in rejecting dreams with such contempt, for instance) is one of the most powerful of the devices with which we are provided as a universal projection against the incursion of unconscious complexes. That is why it is so hard to convince people of the reality of the unconscious and to teach them to recognise something new which in contradiction to their conscious knowledge. [Q142, Freud, 1910, p. 39]
  • Even before puberty extremely energetic repressions of certain instincts have been effected under the influence of education, and mental forces such as shame, disgust and morality have been set up, which like watchmen, maintain these repressions. So that when at puberty the high tide of sexual demands is reached, it is met by these mental reactive or resistant structures like dams. [Q143, Freud, 1910, p. 45]
  • Withdrawal from reality is the main [functional] purpose of [mental] illness but also the main damage caused by it. [Q144, Freud, 1910, p. 49]
  • Drives and their transformations are at the limit of what is discernable by psycho-analysis. From that point it gives place to biological research. [Q145, Freud, 1910, p. 136]
  • You cannot exaggerate the intensity of people’s inner lack of resolution and craving for authority. The extraordinary increase in neurosis since the power of religions has waned may give you a measure of it. The impoverishment of the ego due to the large expenditure of energy on repression demanded of every individual by civilisation may be one of the principal causes of this state of things. [Q146, Freud, 1910, p. 146]

Standard Edition, Volume 12. Case Histories of Schreber, Papers on Technique and Other Works. 1911-1913.


  • The turning away of libido from the external world is a particularly clearly-marked feature in dementia praecox. [Q147, Freud, 1911, p. 77]
  • The shortening of analytic treatment is a justifiable wish, and its fulfilment, as we shall learn, is being attempted along various lines. Unfortunately, it is opposed by a very important factor, namely, the slowness with which deep-going changes in the mind are accomplished – in the last resort, no doubt, the ‘timelessness’ of our unconscious processes. [Q148, Freud, 1911, p. 130]
  • The working through of the resistances may in practice turn out to be an arduous task for the subject of the analysis and a trial of patience for the analyst. Nevertheless it is part of the work which effects the greatest changes in the patient and which distinguishes analytic treatment from any kind of treatment by suggestion. From a theoretical point of view one may correlate it with the ‘abreacting’ of the quotas of affect strangulated by repression – an abreaction without which hypnotic treatment [is] ineffective. [Q149, Freud, 1911, p. 156]
  • Psycho-analytic treatment is founded on truthfulness. In this fact lies a great part of its educative effect and its ethical value. It is dangerous to depart from this foundation. Anyone who has become saturated in the analytic technique will no longer be able to make use of the lies and pretences which a doctor normally finds unavoidable; and if, with the best of intentions, he does attempt to do so, he is very likely to betray himself. [Q150, Freud, 1911, p. 164]
  • In the psychology which is founded on psycho-analysis we have become accustomed to taking as our starting point the unconscious mental processes, with the peculiarities of which we have become acquainted through analysis. We consider these to be the older primary processes, the residues of a phase of development in which they were the only kind of mental processes. [Q151, Freud, 1911b, p. 219]
  • I shall be returning to lines of thought which I have developed elsewhere when I suggest that the state of psychical rest was originally disturbed by the peremptory demands of internal needs. When this happened, what was thought of was simply presented in a hallucinatory manner, just as still happens today with our dream-thoughts every night. [Q152, Freud, 1911b, p. 219]
  • The increased significance of the external world [in our ontogenetic/phylogenetic development] heightened the importance too of the sense-organs that are directed towards that external world, and of the consciousness attached to them. Consciousness now learned to comprehend sensory qualities in addition to the qualities of pleasure and pain which hitherto had alone been of interest to it. A special function was instituted which had periodically to search the external world, in order that its data might be familiar already if an urgent internal need should arise – the function of attention. Its activity meets the sense impressions half-way, instead of awaiting their appearance. [Q153, Freud, 1911b, p. 220]
  • Restraint upon motor discharge (upon action), which then became necessary, was provided by means of the process of thinking, which was developed from the presentation of ideas. Thinking was endowed with characteristics which made it possible for the mental apparatus to tolerate an increased tension of stimulus while the process of discharge was postponed. It is essentially an experimental kind of acting, accompanied by displacement of relatively small quantities of energy together with less expenditure (discharge) of them. For this purpose the conversion of freely displaceable energy into ‘bound’ energy was necessary, and this was brought about by means of raising the whole level of the energetic process. [Q154, Freud, 1911b, p. 221]
  • A general tendency of our mental apparatus, which can be traced back to the economic principle of saving expenditures of energy, seems to find expression in the tenacity with which we hold on to the sources of pleasure at out disposal, and in the difficulty with which we renounce them. With the introduction of the reality principle ones species of thought activity was split off; it was kept free from reality-testing and remained subordinated to the pleasure principle alone. This activity is fantasising, which begins already in children’s play, and later, continued as day-dreaming, abandons dependence on real objects. [Q155, Freud, 1911b, p. 222]
  • Religions have been able to effect absolute renunciation of pleasure in this life by means of the promise of compensation in a future existence; but they have not by this means achieved a conquest of the pleasure principle. It is science which comes nearest to succeeding in that conquest [Q156, Freud, 1911b, p. 224]
  • Frustration has a pathogenic effect because it dams up libido, and so submits the subject to a test as to how long he can tolerate this increase in psychical tension and as to what methods he will adopt for dealing with it. [Q157, Freud, 1912, p. 232]
  • The immediate effect of frustration lies in its bringing into play the dispositional factors which have hitherto been inoperative. Where these are present and sufficiently strongly developed, there is a risk of the libido becoming introverted. It turns away from reality, which owing to the obstinate frustration, has lost its value for the subject, and turns towards the life of fantasy. [Q158, Freud, 1912, p. 232b]
  • As a result of their having reached a particular period of life, and in conformity with regular biological processes, the quantity of libido in their mental economy has experienced an increase which is in itself enough to upset the equilibrium of their health and to set up the necessary conditions for a neurosis. It is well known that more of less sudden increases of libido of this kind are habitually associated with puberty and the menopause… Here the damming-up of libido is the primary factor; it becomes pathogenic as a consequence of a relative frustration on the part of the external world… We may assume that it is not a question of an absolute quantity but of the relation between the quota of libido in operation and the quantity of libido which the individual ego is able to deal with that is, to hold under tension, to sublimate or to employ directly. For this reason a relative increase in the quantity of libido may have the same effect as an absolute one. [Q159, Freud, 1912, p. 236]
  • Unconsciousness seemed to us at first only an enigmatical characteristic of a definite psychical act. Now it means more for us. It is a sign that this act partakes of the nature of a certain psychical category known to us by other and more important characters and that it belongs to a system of psychical activity which is deserving of our fullest attention. The index-value of the unconscious has far outgrown its importance as a property. The system revealed by the sign that the single acts forming parts of it are unconscious we designate by the name ‘The Unconscious’, for want of a better and less ambiguous term. In German, I propose to denote this system by the letters Ubw an abbreviation of the German word ‘Unbewusst’. And this is the third and most significant sense which the term ‘unconscious’ has acquired in psycho-analysis. [Q160, Freud, 1912, p. 266]
  • The characteristics peculiar to both [schizophrenia and paranoia] – megalomania, turning away from the world of objects, increased difficulty in transference – have obliged us to conclude that their dispositional fixation is to be looked for in a stage of libidinal development before object-choice has been established – that is in the phase of auto-erotism and of narcissism. [Q161, Freud, 1912, p. 318]

Standard Edition, Volume 13. Totem and Taboo and Other Works. 1913-1914.


  • It might be maintained that a case of hysteria is a caricature of a work of art, that an obsessional neurosis is a caricature of a religion and that a paranoid delusion is a caricature of a philosophical system. [Q162, Freud, 1913, p. 73]
  • Although we are not yet in a position to describe with sufficient accuracy the characteristics of this narcissistic stage, at which the hitherto dissociated sexual impulses come together into a signal unity and activate the ego as an object, we suspect already that this narcissistic organisation is never wholly abandoned. A human being remains to some extent narcissistic even after he has found external objects for his libido. The activation of objects which he effects are as it were emanations of the libido that still remains in his ego and can be drawn back into once more. The state of being in love, which is psychologically so remarkable and is the normal prototype of the psychoses, shows these emanations at their maximum compared to the level of self-love. [Q162, Freud, 1913, p. 89]
  • The animistic phase would correspond to narcissism both chronologically and in its content; the religious phase would correspond to the stage of object-choice of which the characteristic is a child’s attachment to his parents; while the scientific phase would have an exact counterpart in the stage at which an individual has reached maturity, has renounced the pleasure principle, adjusted himself to reality and turned to the external world for the object of his desires. [Q163, Freud, 1913, p. 90]
  • Psychoanalysis points to psychology for the solution of a good half of the problems of psychiatry. It would nevertheless be a serious mistake to suppose that analysis favours or aims at a purely psychological view of the mental disorders. It cannot overlook the fact that the other half of the problems of psychiatry are concerned with the influence of organic factors on the mental apparatus. Even in the case of the mildest of these disorders, the neuroses, it makes no claim that their origin is purely psychogenic but traces their aetiology to the influence upon mental life of an unquestionable organic factor. [Q164, Freud, 1913, p. 175]
  • Thus it is part of the nature of the mental past that, unlike the historic past, it is not absorbed by its derivatives; it persists (whether actually or only potentially) alongside what has proceeded from it. The proof of this assertion lies in the fact that the dreams of normal people revive their childhood characters every night and reduce their whole mental life to an infantile level. The same return to psychical infantilism (regression) appears in the neuroses and psychoses, whose peculiarities may to a great extent be described as psychical archaisms… The part of a person’s psychical material which has remained infantile and has been repressed as being unserviceable constitutes the core of his unconscious. [Q165, Freud, 1913, p. 184]
  • Whatever we can expect in the way of prophylaxis against neurosis in the individual lies in the hands of a psycho-analytically enlightened education. [Q166, Freud, 1913, p. 190]

Standard Edition, Volume 14. On the History of the Psycho-Analytic Movement, Papers on Metapsychology and Other Words. 1914-1916.


  • The theory of repression is the corner-stone on which the whole structure of psycho-analysis rests. [Q166b, Freud, 1913, p. 16]
  • If anyone sought to place the theory of repression and resistance among the premises instead of the findings of psycho-analysis, I should oppose him most emphatically. Such premises of a general psychological and biological nature do exist, and it would be useful to consider them on some occasion; but the theory of repression is a product of psycho-analytic work, a theoretical inference legitimately drawn from innumerable observations. [Q167, Freud, 1914, p. 17]
  • A pressing motive for occupying ourselves with the conception of primary and normal narcissism arose when the attempt was made to subsume what we know of dementia praecox (Kraepelin) or schizophrenia (Bleuler) under the hypothesis of libido theory. Patients of this kind… display two fundamental characteristics: megalomania and diversion of interest from the external world – from people and things. [Q168, Freud, 1914a, p. 74]
  • With the [paranoid schizophrenic], he seems to have withdrawn his libido from people and things in the external world, without replacing them by others in fantasy. When we does so replace them, the process seems to be a secondary one and to be part of an attempt at recovery, designed to lead the libido back to objects. [Q169, Freud, 1914a, p. 74b]
  • The question arises: What happens to the libido which has been withdrawn from external objects in schizophrenia? The megalomania characteristic of these states points the way. This megalomania has no doubt come into being at the expense of object-libido. The libido that has been withdrawn from the external world has been directed to the ego and thus gives rise to an attitude which may be called narcissism. But the megalomania itself is no new creation; on the contrary, it is, as we know, a magnification and plainer manifestation of a condition which has already existed previously This leads us to look upon the narcissism which arises through the drawing in of object-activity as a secondary one, superimposed upon a primary narcissism that is obscured by a number of different influences. [Q170, Freud, 1914b, p. 75]
  • This extension of the libido theory – in my opinion, a legitimate one – receives reinforcement from a third quarter, namely, from our observations and views on the mental life of children and primitive peoples. In the latter we find characteristics which, if they occurred singly, might be put down to megalomania: an over-estimation of the power of their wishes and mental acts, the omnipotence of thoughts, a belief in the thaumaturgic [magical] force of words, and a technique for dealing with the external world – ‘magic’ – which appears to a logical application of these grandiose premises. [Q171, Freud, 1914b, p. 75b]
  • In children of today, whose development is much more obscure to us, we expect to find an exactly analogous attitude towards the external world. Thus we form the idea of there being an original libidinal activation of the ego, from which some is later given off to objects, but which fundamentally persists and is related to the object-energy much as the body of an amoeba is related to the pseudopodia which it puts out. [Q172, Freud, 1914b, p. 75c]
  • We can see broadly speaking, an antithesis between ego-libido and object-libido. The more of the one is employed, the more of the other becomes depleted. [Q173, Freud, 1914b, p. 76]
  • A unity comparable to the ego cannot exist from the start; the ego has to be developed. [Q174, Freud, 1914b, p. 77]
  • A speculative theory of the relations in question would begin by seeking to obtain a sharply defined concept as its basis. But I am of the opinion that that is just the difference between a speculative theory and a science erected on empirical interpretation. The latter will not envy speculation its privilege of having a smooth, logical unassailable foundation, but will gladly content itself with nebulous, scarcely imaginable basic concepts, which it hopes to apprehend more clearly in the course of its development, or which it is even prepared to replace by others. For these ideas are not the foundation of science, upon which everything else rests: that foundation is observation alone. They are not the bottom but the top of the whole structure, and they can be replaced and discarded without damaging it. The same thing is happening in our day in the science of physics, the basic notions of which as regards matter, centres of force, attraction etc, are scarcely less debatable than the corresponding notions in psycho-analysis. [Q175, Freud, 1914b, p. 77b]
  • We must recollect that all our provisional ideas in psychology will presumably some day be based on an organic substructure. [Q176, Freud, 1914b, p. 78]
  • Just as the transference neuroses have enabled us to trace the libidinal instinctual impulses, so dementia praecox and paranoia will give us insight into the psychology of the ego. [Q177, Freud, 1914b, p. 82]
  • The condition of sleep, too, resembles illness in implying a narcissistic withdrawal o the positions of the libido on to the subject’s own self, or, more precisely, on to the single wish to sleep. The egoism of dreams fits very well in to this context. In both states we have, if nothing else, examples of changes in the distribution of libido that are consequent upon a change in the ego. [Q178, Freud, 1914b, p. 83]
  • The hypochondriac withdraws both interest and libido – the latter specially markedly – from the objects of the external world and concentrates both of them upon the organ that is engaging attention. [Q179, Freud, 1914b, p. 83]
  • The path from introversion [i.e., withdrawal] to regression [e.g., hallucinosis] is to be linked to a damming-up of object-libido. [Q180, Freud, 1914b, 84]
  • At this point, our curiosity will of course raise the question why this damming-up of libido in the ego should have to be experienced as unpleasurable. I shall content myself with the answer that unpleasure is always the expression of a higher degree of tension. [Q181, Freud, 1914b, p. 85]
  • Here we might venture to touch on the question of what makes it necessary at all for our mental life to pass beyond the limits of narcissism and to attach the libido to objects. The answer which would follow from our line of thought would once more be that this necessity arises when the filling of the ego with libido exceeds a certain amount. A strong egoism is a protection against falling ill, but in the last resort we must begin to love in order not to fall ill, and we are bound to fall ill if, in consequence of frustration, we are unable to love. [Q182, Freud, 1914b, p. 85b]
  • In [paranoid schizophrenia] megalomania allows of a similar internal working over of libido which has returned to the ego; perhaps it is only when the megalomania fails that the damming up of libido in the ego becomes pathogenic and starts the process of recovery which gives us the impression of being a disease. [Q183, Freud, 1914b, p. 86]
  • The difference between paranoid schizophrenia and the transference neuroses appears to me to lie in the circumstance that, in the former, the libido that is liberated by frustration does not remain attached to objects in fantasy, but withdraws on to the ego. Megalomania would accordingly correspond to the psychical mastering of the latter amount of libido and would thus be the counterpart of the introversion on to fantasies that is found in the transference neuroses. [Q184, Freud, 1914b, p. 86b]
  • Repression we have said proceeds from the ego, we might say with greater precision that it proceeds from the self-respect of the ego. [Q185, Freud, 1914b, p. 93]
  • For the ego, the formation of an ideal would be the conditioning factor of repression. [Q186, Freud, 1914b, p. 94]
  • The ego ideal is now the target of the self-love which was once enjoyed in childhood by the actual ego. The subject’s narcissism makes its appearance displaced on to this new ideal ego, which, like the infantile ego, finds itself possessed of every perfection that is of value. As always where the libido is concerned, man has here shown himself to be incapable of giving up a satisfaction he had once enjoyed. He is not willing to forgo the narcissistic perfection of his childhood; and when as he grows up, he is disturbed by the admonitions of others and by the awakening of his own critical judgment, so that he can no longer retain that perfection, he seeks to recover it in the new form of an ideal. What he projects before him as his ideal is the substitute for the lost narcissism of his childhood in which he was his own ideal. [Q187, Freud, 1914b, p. 94b]
  • It would not surprise us if we were to find a special psychical agency which performs the task of seeing that narcissistic satisfaction from the ego ideal is ensured and which, with this end in view, constantly watches the actual ego and measures it by that ideal. If such an agency does exist, we cannot possible come upon it as a discovery – we can only recognise it; for we may reflect that what we call ‘conscience’ has the required characteristics. Recognition of this agency enables us to understand the so-called ‘delusions of being noticed’ or more correctly, of being watched, which are such striking symptoms in the paranoid diseases. [Q188, Freud, 1914b, p. 95]
  • Paranoid patients complain that all their thoughts are known and their actions watched and supervised; they are informed of the functioning of this agency by voices which characteristically speak to them in the third person ‘Now she’s thinking of that again’, ‘now he’s going out’. This complaint is justified; it describes the truth. A power of this kind, watching, discovering and criticising all our intentions, does really exist. Indeed, it exists in everyone of us in normal life. [Q189, Freud, 1914b, p. 95]
  • For what prompted the subject to form an ego ideal, on whose behalf his conscience acts as a watchman, arose from the critical influence of his parents (conveyed to him by the medium of the voice) to whom were added, as time went on, those who trained and taught him and the innumerable and indefinable host of all the other people in his environment – his fellow men – and public opinion. [Q190, Freud, 1914b, p. 96]
  • The institution of conscience was at bottom an embodiment, first of parental criticism and subsequently of that of society – a process which is repeated in what takes place when a tendency towards repression develops out of a prohibition of obstacle that came in the first from without. [Q191, Freud, 1914b, p. 96]
  • The voices, as well as the undefined multitude, are brought into the foreground again by the disease [schizophrenia], and so the evolution of conscience is reproduced regressively. But the revolt against this ‘censoring agency’ arises out of the subject’s desire (in accordance with the fundamental character of his illness) to liberate himself from all these influences… His conscience then confronts him in a regressive form as a hostile influence from without. [Q192, Freud, 1914b, p. 96b]
  • Thus the activity of the mind which has taken over the function of conscience has also placed itself at the service of internal research, which furnishes philosophy with the material fro its intellectual operations. This may have some bearing on the characteristic tendency of paranoics to construct speculative systems. [Q193, Freud, 1914b, p. 96c]
  • It is easy to observe that libidinal object-investment does not raise self-regard. The effect of dependence upon the loved object is to lower that feeling: a person in love is humble. A person who loves has, so to speak, forfeited a part of his narcissism, and it can only be replaced by his being loved. [Q194, Freud, 1914b, p. 98]
  • It is also true that a real happy love corresponds to the primal condition in which object-libido and ego-libido [object and subject] cannot be distinguished. [Q195, Freud, 1914b, p. 100]
  • The development of the ego consists in a departure from primary narcissism and gives rise to a vigorous attempt to recover that state. This departure is brought about by means of the displacement of libido on to an ego ideal imposed from without; and satisfaction is brought about from fulfilling this ideal. At the same time the ego has sent out the libidinal object-investments. It becomes impoverished in favour of these investments, just as it does in favour of the ego ideal, and it enriches itself once more from its satisfactions in respect of the object, just as it does by fulfilling its ideal. One part of the self-regard is primary – the residue of infantile narcissism; another part arises out of the omnipotence which is corroborated by experience (the fulfilment of the ego ideal), whilst a third part proceeds from the satisfaction of object-libido. [Q196, Freud, 1914b, p. 100]
  • We have often heard it maintained that sciences should be built up on clear and sharply defined basic concepts. In actual fact no science, not even the most exact, beings with such definitions. The true beginning of scientific activity consists rather is describing phenomena and then in proceeding to group, classify and correlate them. [Q197, Freud, 1915, p. 117]
  • We thus arrive at the essential nature of drives in the first place by considering their main characteristics – their origin in sources of stimulation within the organism and their appearance as a constant force. [Q198, Freud, 1915, p. 119]
  • The nervous system is an apparatus which has the function of getting rid of stimuli that reach it, or of reducing them to the lowest possible level’ or which, if it were feasible, would maintain itself in an altogether unstimulated condition. [Q199, Freud, 1915, p. 120]
  • Let us for the present not take exception to the indefiniteness of this idea and let us assign to the nervous system the task – speaking in general terms – of mastering stimuli. [Q200, Freud, 1915, p. 120]
  • If now we apply ourselves to considering mental life from a biological point of view, a ‘drive’ appears to us as a concept on the frontier between the mental and the somatic, the psychical representation of the stimuli originating from within the organism and reaching the mind, as a measure of the demand made upon the mind fro work in consequence of its connection with the body. [Q201, Freud, 1915, p. 122]
  • The object of a drive is the thing in regard to which or through which the instinct is able to achieve its aim. [Q202, Freud, 1915, p. 122b]
  • Marked instinctual ambivalence in a human being living at the present day may be regarded as an archaic inheritance, for we have reason to suppose that the part played in instinctual life by the active impulses in their unmodified form was greater in primaeval times than it is on average today. [Q203, Freud, 1915, p. 131]
  • The antithesis active-passive must not be confused with the antithesis ego-subject external world-object. The relation of the ego to the external world is passive in so far as it receives stimuli from it and active when it reacts to these. [Q204, Freud, 1915, p. 134]
  • Hate, as a relation to objects, is older than love. It derives from the narcissistic ego’s primordial repudiation of the external world. [Q205, Freud, 1915, p. 139]
  • Under certain conditions, which we shall presently investigate more closely, the impulse then passes into a state of ‘repression’. If what was in question was the operation of an external stimulus, the appropriate method to adopt would obviously be flight; with a drive, flight is of no avail, for the ego cannot escape from itself. At some later period, rejection based on judgment (condemnation) will be found to be a good method to adopt against an instinctual impulse. Repression is a preliminary stage of condemnation, something between flight and condemnation; it is a concept which could not have been formulated before the time of psycho-analytic studies. [Q205, Freud, 1915, p. 146]
  • The essence of repression lies simply in turning something away, and keeping it at a distance, from the conscious. [Q206, Freud, 1915, p. 147]
  • We have reason to assume that there is a primal repression, a first phase of repression, which consists in the psychical (ideational) representative of the drive being denied entrance into the conscious. [Q207, Freud, 1915, p. 148]
  • This deceptive strength of drive is the result of an uninhibited development in fantasy and of the damming-up consequent on frustrated satisfaction. The fact that this last result is bound up with repression points the direction in which the true significance of repression has to be looked for. [Q208, Freud, 1915, p. 149]
  • The process of repression is not to be regarded as event which takes place once, the results of which are permanent, as when some living thing has been killed and from that time onward is dead; repression demands a persistent expenditure of force, and if this were to cease the success of the repression would be jeopardised, so that a fresh act of repression would be necessary. We may suppose that the repressed exercises a continuous pressure in the direction of the conscious, so that this pressure must be balanced by an unceasing counter-pressure. Thus the maintenance of a repression involves an uninterrupted expenditure of force, while its removal results in a saving from an economic point of view. [Q209, Freud, 1915, p. 151]
  • The mechanisms of repression have at least this one thing in common: a withdrawal of the investment of energy. [Q210, Freud, 1915, p. 155]
  • The vanished affect comes back in its transformed shape as social anxiety, moral anxiety and unlimited self-reproaches. [Q211, Freud, 1915, p. 157]
  • We have learnt from psycho-analysis that the essence of the process of repression lies, not in putting an end to, in annihilating, the idea which represents a drive but in preventing it from becoming conscious. [Q212, Freud, 1915b, p. 166]
  • Everything that is repressed must remain unconscious; but let us state at the very outset that the repressed does not cover everything that is unconscious. The unconscious has the wider compass: the repressed is a part of the unconscious. [Q213, Freud, 1915b, p. 166b]
  • How are we to arrive at a knowledge of the unconscious? It is of course only as something conscious that we know of it, after it has undergone transformation or translation into something conscious. [Q214, Freud, 1915b, p. 166c]
  • When all our latent memories are taken into consideration it becomes incomprehensible how the existence of the unconscious can be denied. [Q215, Freud, 1915b, p. 167]
  • Incidentally, even before the time of psycho-analysis, hypnotic experiments, and especially post-hypnotic suggestion, had tangibly demonstrated the existence and mode of operation of the mental unconscious. [Q216, Freud, 1915b, p. 169]
  • Without any special reflection we attribute to everyone else our own constitution and therefore our consciousness as well, and that this identification is a sine qua non of our understanding. This inference (or this identification) was formerly extended by the ego to other human beings, to animals, plants, inanimate objects and to the world at large, and proved serviceable so long as their similarity to the individual ego was overwhelmingly great; but it became more untrustworthy in proportion as the difference between the ego and these others widened. [Q217, Freud, 1915b, p. 169b]
  • This process of inference, when applied to oneself in spite of internal opposition, does not, however, lead to the disclosure of an unconscious; it leads logically to the assumption of another, second consciousness which is united in oneself with the consciousness one knows. [Q218, Freud, 1915b, p. 170]
  • In psychoanalysis there is no choice for us but to assert that mental processes are in themselves unconscious, and to liken the perception of them by means of consciousness to the perception of the external world by means of the sense organs. [Q219, Freud, 1915b, p. 171]
  • The unconscious comprises, on the one hand, acts which are merely latent, temporarily unconscious, but which differ in no other respect from conscious ones and, on the other hand, processes such as repressed ones, which if they were to become conscious would be bound to stand out in the crudest contrast to the rest of the conscious processes. [Q220, Freud, 1915b, p. 172]
  • We cannot escape the ambiguity of using the words ‘conscious’ and ‘unconscious’, sometimes in a descriptive and sometimes in a systematic sense, in which the latter signify inclusion in particular systems and possessions of certain characteristics. [Q221, Freud, 1915b, p. 172b]
  • Or are we rather to be believe that the transposition consists in a change in the state of the idea, a change involving the same material and occurring in the same locality? This question may appear abstruse, but it must be raised if we wish to form a more definite conception of the psychical topography, of the dimension of depth in the mind. It is a difficult one because it goes beyond pure psychology and touches on the relations pf the mental apparatus to anatomy. We know that in the very roughest sense such relations exist. Research has given irrefutable proof that mental activity is bound up with the function of the brain as it is with no other organ. [Q222, Freud, 1915b, p. 174]
  • There is a hiatus here which at present cannot be filled, nor is it one of the tasks of psychology to fill it. Our psychical topography has for the present nothing to do with anatomy; it has reference not to anatomical localities but to regions in the mental apparatus wherever they may be situated in the body. [Q223, Freud, 1915b, p. 175]
  • Strictly speaking, then, and although no fault can be found with the linguistic usage, there are no unconscious affects as there are unconscious ideas. But there may very well be in the system Ucs, affective structures which, like others, become conscious. The whole difference arises from the fact that ideas are activations/investments – basically of memory-traces, whilst affects and emotions correspond to processes of discharge. [Q224, Freud, 1915b, p. 178]
  • The transition from the system Ucs to the [ego] is not effected through the making of a new registration but through a change in its state, an alteration in its energy/activation. [Q225, Freud, 1915b, p. 180]
  • Besides the dynamic and the topographical points of view, we have adopted the economic This endeavours to follow out the vicissitudes of amounts of excitation and to arrive at least at some relative estimate of their magnitude. [Q226, Freud, 1915b, p. 181]
  • The distinction we have made between the two psychical systems receives fresh significance when we observe that processes in the one system, the Ucs, show characteristics which are not met with again the system immediately above it [the ego]. [Q227, Freud, 1915b, p. 186]
  • The energetic intensities in the Ucs are much more mobile. By the process of displacement one idea may surrender to another its whole quote of energy; by the process of condensation it may appropriate the whole energy of several other ideas. I have proposed to regard these two processes as distinguishing marks of the so-called primary psychical process. In the [ego], the secondary process is dominant. When a primary process is allowed to take its course in connection with elements belonging to the ego, it appears comic and excites laughter. [Q228, Freud, 1915b, p. 186b]
  • The processes of the system Ucs are timeless; i.e., they are not ordered temporally, are not altered by the passage of time; they have no reference to time at all. Reference to time is bound up, once again, with the work of the [ego]. [Q229, Freud, 1915b, p. 187]
  • To sum up: exemption from mutual contradiction [e.g., opposite emotions existing together], timelessness and replacement of external by psychical reality – these are the characteristics which we may expect to find in processes belonging to the system Ucs. [Q230, Freud, 1915b, p. 187b]
  • Unconscious processes only become cognizable by us under conditions of dreaming and of neurosis – that is to say, when the process of the higher [ego] system are set back to an earlier stage… In themselves they cannot be cognized, indeed are even incapable of carrying on their existence; for the system Ucs is at a very early moment overlaid by the ego which has taken over access to consciousness and to motility. [Q231, Freud, 1915b, p. 188]
  • The full significance of the characteristics of the system Ucs described above could only be appreciated by us if we were to contrast them with those of the system Ucs. [Q232, Freud, 1915b, p. 188b]
  • Breuer [assumed] the existence of two different states of energy in mental life: one in which the energy is tonically ‘bound’ and the other is which it is freely mobile and presses towards discharge. In my opinion this distinction represents the deepest insight we have gained up to the present into the nature of nervous energy. [Q233, Freud, 1915b, p. 188b]
  • Further, it devolves upon the [ego] to make communication possible between the different ideational contents so that they can influence one another, to give them an order in time, and to set up a censorship or several censorships; ‘reality-testing’ too, and the reality-principle are its province. Conscious memory, moreover, seems to depend on the [ego]. This should clearly be distinguished from the memory-traces in which the experiences of the Ucs are fixed. [Q234, Freud, 1915b, p. 189]
  • We are describing the state of affairs as it appears in the adult human being, in whom the system Ucs operates, strictly speaking, only as a preliminary stage of the higher organisation. [Q235, Freud, 1915b, p. 189b]
  • Moreover, in human beings we must be prepared to find possible pathological conditions under which the two systems alter, or even exchange, both their content and their characteristics. [Q236, Freud, 1915b, p. 189c]
  • It would nevertheless be wrong to imagine that the Ucs remains at rest while the whole work of the mind is performed by the [ego] – that the Ucs is something finished with, a vestigial organ, a residuum from the process of development. It is wrong also to suppose that communication between the two systems is confined to the act of repression, with the [ego] casting everything that seems disturbing to it into the abyss of the Ucs. On the contrary, the Ucs is alive and capable of development and maintains a number of other relations with the [ego] amongst them that of cooperation. [Q237, Freud, 1915b, p. 190]
  • The act of becoming conscious is dependent on the attention of the [ego] being turned in certain directions. [Q238, Freud, 1915b, p. 192]
  • The more we seek to win our way to a metapsychological [i.e., a mechanistic] view of mental life, the more we must learn to emancipate ourselves from the importance of the symptom of ‘being conscious’. [Q239, Freud, 1915b, p. 193]
  • The existence of the censorship between the [ego] and [consciousness] teaches us that becoming conscious is no mere act of perception, but is probably also a hyperactivation,, a further advance in the psychical organisation. [Q240, Freud, 1915b, p. 194]
  • The unconscious is also affected by experiences originating from external perception. Normally all the paths from perception to the Ucs remain open and only those leading on from the Ucs are subject to blocking by repression. [Q241, Freud, 1915b, p. 194b]
  • The content of the Ucs may be compared with an aboriginal population in the mid. If inherited mental formations exist in the human being – something analogous to instinct in animals – these constitute the nucleus of the Ucs. Later there is added to them what is discarded during childhood development as unserviceable, and this need not differ in its nature from what is inherited. A sharp and final division between the content of the two systems does not, as a rule, take place till puberty. [Q242, Freud, 1915b, p. 195]
  • We have tried to base our characterisation of Kraepelin’s dementia praecox (Bleuler’s schizophrenia) on its position with reference to the antithesis between ego and object. [Q243, Freud, 1915b, p. 196]


  • In the case of schizophrenia, on the other hand, we have been driven to the assumption that after the process of repression the libido that has been withdrawn does not seek a new object but retreats into the ego; that is to say, that here the object-investments are given up and a primitive objectless condition of narcissism is re-established. The incapacity of these patients for transference (so far as the pathological process extends), their consequent inaccessibility to therapeutic efforts, their characteristic repudiation of the external world, the appearance of signs of a hyper-activation of their own ego, the final outcome in complete apathy – all these clinical features seem to agree excellently with the assumption that their object-investments have been given up. [Q244, Freud, 1915b, p. 197]
  • As regard the relation of the two psychical systems to each other, all observers have been struck by the fact in schizophrenia a great deal is expressed as being conscious which in the transference neuroses can only be shown to be present in the Ucs by psycho-analysis. [Q245, Freud, 1915b, p. 197b]
  • In schizophrenia we observe – especially in the initial stages, which are so instructive – a number of changes in speech, some of which deserve to be regarded from a particular point of view. The patient often devotes peculiar care to his way of expressing himself, which becomes stilted and precious. The construction of his sentences undergoes a peculiar disorganisation. [Q246, Freud, 1015b, p. 197c]
  • In schizophrenia words are subjected to the same process as that which makes the dream images out of the latent dream-thoughts – to what we have called the primary psychical process. They undergo condensation and by means of displacement transfer their energy to one another in their entirety. The process may go so far that a single word, if it specially suitable in account of its numerous connections, takes over the representation of a while train of thought. [Q247, Freud, 1915, p. 199]
  • If now we put this finding alongside the hypothesis that in schizophrenia object-investments are given up, we shall be obliged to modify the hypothesis by adding that the investment of the word-presentation of objects is retained. What we have permissibly called the conscious presentation of the object can now be split up into the presentation of the word and the presentation of the thing; the latter consists in the activation, if not of the direct memory-images of the thing, at least of remoter memory-traces derived from these. [Q248, Freud, 1915b, p. 202]
  • The conscious presentation comprises the presentation of the thing plus the presentation of the word belonging to it, while the unconscious presentation is the presentation of the thing alone. The system Ucs contains the thing-activations of the objects, the first and true object-activations; the [ego] comes about by this thing presentation being hyper-activated through being linked with word-presentations corresponding to it. It is these hyperactivations, we may suppose, that bring about a higher psychical organisation and make it possible for the primary process to be succeeded by the secondary process which is dominant in the ego. Now too, we are in a position to state precisely what it is that repression denies to the rejected presentation in the transference neuroses: what it denies to the presentation is translation into words, which shall remain attached to the object. A presentation which is not put into words, or a psychical act which is not hyperactivated, remains therefore in the Ucs in a state of repression. [Q249, Freud, 1915b, p. 202b]
  • Probably, however, thought proceeds in systems so far remote from the original perceptual residues that they have no longer retained anything of the qualities of those residues, and, in order to become conscious, need to be reinforced by new qualities. Moreover, by being linked with words, activations can be provided with quality, even when they present only relations between presentations of objects and are thus unable to derive any quality from perceptions. Such relations, which become comprehensible only through words, form a major part of out thought processes. [Q250, Freud, 1915b, p. 202c]
  • As we can see, being linked with word-presentation is not yet the same thing as becoming conscious, but only makes it possible to become so; it is therefore characteristic of the [ego] and of that system alone. [Q251, Freud, 1915b, p. 202-203]
  • The ego’s attempt at flight, which expresses itself in the withdrawal of the conscious activation, nevertheless remains a factor common to [transference and narcissistic neuroses]. The most superficial reflection shows us how much more radically and profoundly this attempt at flight, this flight of the ego, is put into operation is the narcissistic neuroses. [Q252, Freud, 1915b, p. 203]
  • If in schizophrenia, this flight consists in withdrawal of instinctual energy from the points which represent the unconscious presentation of the object, it may seems strange that the part of the presentation of this object which belongs to the [ego] namely – word presentation corresponding to it – should, on the contrary receive a major activation… It turns out that the activation of the word presentation is not part of the act of repression but represents the first of the attempts at recovery or cure which so conspicuously dominate the clinical picture of schizophrenia. [Q253, Freud, 1915b, p. 203-204]
  • These endeavours are directed towards regaining the lost object and it may well be that to achieve this purpose they set off on a path that leads to the object via the verbal part of it, but then find themselves obliged to be content with words instead of things. It is a general truth that our mental activity moves in two opposite directions: either it starts from the instincts and passes through the system Ucs to conscious thought-activity; or, beginning with an instigation from outside, it passes through the [ego] till; it reaches the Ucs activations of the ego and objects. This second path must in spite of the repression which has taken place, remain traversable, and it lies open to some extent to the endeavours make by the neuroses to regain its objects. When we think in abstractions there is a danger that we may neglect the relations of words to unconscious thing-presentations. [Q253, Freud, 1915b, p. 204b]
  • We learn to speak the language of other people by endeavouring to make the sound-image produced by ourselves as like as possible to the one which gave rise to our speech innervation. [Q254, Freud, 1891, p. 211]
  • A dream is, therefore, among other things, a projection: an externalisation of an internal process. [Q255, Freud, 1917, p. 223]
  • The essential difference between the dream-work and schizophrenia becomes clear. In the latter, what becomes the subject of modification by the primary process are the words themselves…; in dreams, what are subject to modification are not the words but the thing-presentations to which the words have been taken back. In dreams there is topographical regression [i.e., the system Ucs and the primary process becoming dominant]; in schizophrenia there is not. In dreams there is free communication between the [ego] word-activations and the Ucs thing-activations, while it is characteristic of schizophrenia that this communication is cut off. [Q256, Freud, 1917, p. 229]
  • Hallucination consists in an activation of the perceptual system which however, is not effected – as normally – from without but from within. [Q257, Freud, 1917, p. 232]
  • This function of orienting the individual in the world by discrimination between what is internal and what is external must now after detailed dissection of the mental apparatus, be ascribed to the perceptual system alone. This system must have at its disposal a motor innervation which determines whether the perception can be made to disappear or whether it proves resistant. Reality-testing need be nothing more than this contrivance. [Q258, Freud, 1917, p. 233]
  • We shall place reality-testing among the major institutions of the ego, alongside the censorships which have come to recognise between the psychical systems. [Q259, Freud, 1917, p. 233b]
  • With this turning away from reality, reality-testing is got rid of, the wishful fantasies are able to press forward into the system and they are there regarded as a better reality. [Q260, Freud, 1917, p. 233c]
  • Amentia [hallucinatory delirium] presents the interesting spectacle of a breach between the ego and one of its organs [the hippocampus?] one which had perhaps been its most faithful servant and had been bound up with it most intimately. [Q261, Freud, 1917, p. 233d]
  • As regards the hallucinatory psychosis of dementia praecox, we shall infer from our discussion that that psychosis cannot be among the initial symptoms of the affection. It becomes possible only when the patient’s ego is so far disintegrated that reality-testing no longer stands in its way. [Q262, Freud, 1917, p. 234]
  • In mourning, reality-testing has shown that the loved object no longer exists and it proceeds to demand that all libido shall be withdrawn from its attachments to that object… Opposition to this can be so intense that a turning away from reality takes place and a clinging to the object through the medium of a hallucinatory wishful psychosis. [Q263, Freud, 1917b, p. 244]
  • Melancholia is in some way related to an object-loss which is withdrawn from consciousness, in contradistinction to mourning, in which there is nothing about the loss that is unconscious. [Q264, Freud, 1917, p. 245]
  • In mourning we found that the inhibition and loss of interest are fully accounted for by the work of mourning in which the ego is absorbed. In melancholia, the unknown loss will result in a similar internal work and will therefore be responsible for the melancholic inhibition. [Q265, Freud, 1917b, p. 245b]
  • We see how in hum one part of the ego sets itself over against the other, judges it critically and as it were takes it as its object. Our suspicion that the critical agency which is here split off from the ego might also show its independence in other circumstances will be confirmed by every further observation. We shall really find grounds for distinguishing this agency from the rest of the ego. What we are here becoming acquainted with is the agency commonly called ‘conscience’; we shall count it, along with the censorship of consciousness and reality-testing, among the major institutions of the ego, and we shall come upon evidence to show that it can become diseased in its own account. [Q266, Freud, 1917b, p. 247]
  • There is no difficulty in reconstructing [the] process of [melancholia]. An object-choice, an attachment of the libido to a particular person, had at one time existed; then, owing to a real slight or disappointment coming from this loved person, the object-relationship was shattered… But the free libido was not displaced on to another object; it was withdrawn into the ego… Thus the shadow of the object fell upon the ego and the latter could henceforth be judged by a special agency, as though it were the forsaken object… One or two things may be directly inferred with regards to the preconditions and effects of a process such as this. On the one hand, a strong fixation to the loved object must have been present; on the other hand, in contradiction to this, the object-[investment] must have had little power of resistance… This contradiction seems to imply that the object-choice had been effected on a narcissistic basis, so that the object-[investment], when obstacles [came] in its way, [could] regress to narcissism. [Q267, Freud, 1917b, p. 249]
  • Recovery in a case of schizophrenia; it represents, of course, a regression from one type of object choice to original narcissism. We have elsewhere shown that identification is a preliminary stage of object-choice, that it is the first way – and one that is expressed in an ambivalent fashion – in which the ego picks out an object. The ego wants to incorporate this object into itself, and, in accordance with the oral or cannibalistic phase of libidinal development in which it is, it wants to do so by devouring it. [Q268, Freud, 1917b, p. 250]
  • Melancholia therefore borrows some of its features from mourning and the others from the process of regression from narcissistic object-choice to narcissism. [Q269, Freud, 1917b, p. 250]
  • The loss of a love-object is an excellent opportunity for the ambivalence in love-relationships to make itself effective and come into the open. Where there is a disposition to obsessional neurosis the conflict die to ambivalence gives a pathological cast to mourning and forces it to express itself in the form of self-reproaches to the effect that the mourner himself is to blame for the loss of the loved object i.e., he has willed it. [Q270, Freud, 1917b, p. 251]
  • If the love for the object – a love which cannot be given up though the object itself is given up –takes refuge in narcissistic identification, then the hate comes into operation on this substitutive object, abusing it, debasing it, making it suffer and deriving sadistic satisfaction from its suffering. The self-tormenting in melancholia which is without doubt enjoyable signifies just like the corresponding phenomenon in obsessional neurosis a satisfaction of trends of sadism and hate which relate to an object and which have been turned round upon the subject’s own self. [Q271, Freud, 1917b, p. 251b]
  • In taking revenge on the original object and in tormenting their loved one through their illness, having resorted to it in order to avoid the need to express to express their hostility to him openly. [Q272, Freud, 1917b, p. 251c]
  • It is this sadism alone that solves the riddle of the tendency to suicide which make melancholia so interesting and so dangerous. So immense is the ego’s self-love, which we have come to recognise as the primal state rom which instinctual life proceeds, and so vast is the amount of narcissistic libido which we see liberated in the fear that emerges at a threat to life, that we cannot conceive how that ego can consent to its own destruction. We have long known, it is true, that no neurotic harbours thoughts of suicide which he has not turned back upon himself from murderous impulses against others. [Q273, Freud, 1917b, 252]
  • In the two opposed situations of being most intensely in love and of suicide the ego is overwhelmed by the object though in totally different ways. [Q274, Freud, 1917b, p. 252b]
  • The manic subject plainly demonstrates his liberation from the object which was the cause of his suffering by seeking like a ravenously hungry man for new object-activations. [Q275, Freud, 1917b, p. 255]
  • Each single one of the memories and situations of expectancy which demonstrate the libido’s attachment to the lost object is met by the verdict of reality that the object no longer exists; and the ego, confronted as it were with the question whether it shall share this fate,, is persuaded by the sum of the narcissistic satisfactions it derives from being alive to sever its attachment to the object that has been abolished. We may perhaps suppose that this work of severance is so slow and gradual that by the time it has been finished the expenditure of energy necessary for it has dissipated. [Q276, Freud, 1917b, p. 255b]
  • The accumulation of energy which is at first bound and then, after the work of melancholia is finished, becomes free and makes mania possible must be linked with regression of the libido to narcissism. The conflict within the ego, which melancholia substitutes for the struggle over the object, must act like a painful wound which calls for an extraordinarily high inhibitory force [repression]. [Q277, Freud, 1917b, p. 258]
  • When a village grows into a town or child into a man, the village and the child become lost in the town and the man. [Q278, Freud, 1915c, p. 285]
  • The primitive mind is, in the fullest meaning of the word, imperishable. [Q279, Freud, 1915c, p. 286]
  • The man of prehistoric times survives unchanged in our unconscious. Our unconscious then, does not believe in its own death; it behaves as if it were immortal. [Q280, Freud, 1915c, p. 296]

Standard Edition, Volume 15. Introductory Lectures on Psycho-Analysis. Parts I & II. 1915-1916.

  • The prehistory into which the dreamwork leads us back is of two kinds – on the one hand, into the individual’s prehistory, his childhood and on the other, in so far as each individual somehow recapitulates in an abbreviated form the entire development of the human race, into phylogenic history too… It seems to me that symbolic connections, which the individual has never acquired by learning may justly claim to be regard as a phylogenetic heritage. [Q281, Freud, 1916, p. 199]
  • The regression of the dreamwork is not only a formal one but also a material one. It not only translates our thoughts into a primitive form of expression; but it also revives the characteristics of our primitive mental life. [Q282, Freud, 1916, p. 211]

Standard Edition, Volume 16. Introductory Lectures on Psychoanalysis. Part III. 1916-1917.


  • We can say that the mental apparatus serves the purpose of mastering and disposing of the amounts of stimulus and sums of excitation that impinge on it from outside and inside. [Q283, Freud, 1917c, p. 356-357]
  • A nature reserve preserves its original state which everywhere else has to our regret been sacrificed to necessity. Everything, including what is useless and even what is noxious, can grow and proliferate there as it pleases. The mental realm of fantasy is just such reservation withdrawn from the reality principle… The best known productions of fantasy are the day-dreams [Q284, Freud, 1917c, p. 372]
  • The ultimate aim of mental activity, which may be described qualitatively as an endeavour to obtain pleasure and avoid unpleasure, emerges, looked at from the economic point of view, as the task of mastering the amounts of excitation (mass of stimuli) operating in the mental apparatus and of keeping down their accumulation which creates unpleasure. [Q285, Freud, 1917c, p. 375]
  • Repression corresponds to an attempt at flight by the ego from libido which is felt as danger. [Q286, Freud, 1917c, p. 410]
  • I have already spoken to you of the [inhibitory action] which is employed by the ego in the process of repression which must be permanently maintained in order that the repression may have stability. [Q287, Freud, 1917c, p. 411]
  • The question then arose of what happened to the libido of dementia praecox patients which was turned away from objects. Abraham did not hesitate to give the answer: it is turned back on to the ego and this reflexive turning-back is the source of the megalomania in dementia praecox. [Q288, Freud, 1917c, p. 415]
  • We pictured the relation of ego-libido to object-libido in a way which I can make plain to you by an analogy from zoology. Think of those simplest of living organisms [the amoebas] which consist of a little differentiated globule of protoplasmic substance. They put out protrusions, known as pseudopodia, into which they cause the substance of their body to flow over. They are able, however, to withdraw the protrusions once more and form themselves again into a globule. We compare the putting out of these protrusions, then, to the emission of libido on to objects while the main mass of libido can remain in the ego; and we suppose that in normal circumstances ego-libido can be transformed unhindered into object libido and that this can once more be taken back into the ego. [Q289, Freud, 1917c, p. 416]
  • In a sleeper the primal state of distribution of the libido is restored – total narcissism, in which libido and ego-interest, still united and indistinguishable, dwell in the self-sufficing ego. [Q290, Freud, 1917c, p. 417]
  • It is possible to be absolutely egoistic and yet maintain powerful object-activations, in so far as the libidinal satisfaction in relation to the object froms part of the ego’s needs. In that case, egoism will see to it that striving for the object involves no damage to the ego. It is possible to be egoistic and at the same time to be excessively narcissistic – that is to say, to have very little need for an object. [Q291, Freud, 1917c, p. 417c]
  • When a particular, very energetic process forces a withdrawal of libido from objects. Here the libido that has become narcissistic cannot find its way back to objects and this interference with the libido’s mobility certainly becomes pathogenic. It seems that an accumulation of narcissistic libido beyond a certain amount is not tolerated. We may even imagine that it was for that very reason that object-activations originally came about, that the ego was obliged to send out its libido so as not to fall ill as a result of its being dammed up. [Q292, Freud, 1917c, p. 421]
  • The clinical picture of dementia praecox (which incidentally, is very changeable) is not determined exclusively by the symptoms arising the forcing away of the libido from objects and its accumulation in the ego as narcissistic libido. A large part, rather, is played by other phenomena, which are derived from efforts of the libido to attain objects once more and which thus correspond to an attempt at restitution or recovery. These latter symptoms are indeed the more striking and noisy… It seems as though in dementia praecox the libido, in its efforts once more to reach objects (that is, the presentation of objects), does in fact snatch hold of something of them, but, as it were, only their shadows – I mean the word-presentations belonging to them. [Q293, Freud, 1917c, p. 422]
  • We have discovered that the self-reproaches, with which these melancholic patients torment themselves in the most merciless fashion, in fact apply to another person, the sexual object which they have lost or which has become valueless to them through its own fault. From this we can conclude that the melancholic has, it is true, withdrawn his libido from the object, but that, by a process which we must call ‘narcissistic identification’, the object has been set-up in the ego itself, has been, as it were projected into the ego… The subject’s own ego is then treated like the object that has abandoned, and it is subjected to all the acts of aggression and expressions of vengefulness which have been aimed at the object. A melancholic’s propensity to suicide is also made more intelligible if we consider that the patient’s embitterment strikes with a single blow at his own ego and at the loved and hated object. [Q294, Freud, 1917c, p. 427]
  • From the analysis of delusions of observation we have drawn the conclusion that there actually exists in the ego an agency which unceasingly observes, criticises and compares and in that way sets itself over against the other part of the ego. [Q295, Freud, 1917c, p. 428]
  • He senses an agency holding sway in his ego which measures his actual ego and each of its activities by an ideal ego that he has created for himself in the course of development… When in delusions of observation it becomes split up, it reveals to us its origins from the influence of parents, educators and social environment – from an identification with some of these model figures. [Q296, Freud, 1917c, p. 429]
  • On the basis of our clinical impressions we maintained that [schizophrenic] patients’ object-activations must have been given up and that their libido must have been transformed into ego-libido. Through this characteristic we distinguished them from the first group of neurotics… This suspicion is now confirmed by their behaviour in our attempts at therapy. They manifest no transference and for that reason are inaccessible to our efforts and cannot be cured by us. [Q297, Freud, 1917c, p. 447]

Standard Edition, Volume 17. An Infantile Neurosis and Other Works. 1917-1919.

  • I will add that all the narcissistic impulses operate from the ego and have their permanent seat in the ego. [Q298, Freud, 1918, p. 111]
  • His extraordinary propensity to ambivalence, and (as a third trait [of the unconscious] in a constitution which deserves the name archaic) his power of maintaining simultaneously the most various and contradictory libidinal activations, all of them functioning side by side. [Q299, Freud, 1918, p. 119]
  • We have been driven to assume that at the beginning of the development of the individual all his libido (all his erotic tendencies, all his capacity for love) is tied to himself – that as we say, it [fills] his own ego. It is only later that, being attached to the satisfaction of the major vital needs, the libido flows over from the ego on to external objects… The condition in which the ego retains the libido is called by us ‘narcissism’, in reference to the Greek legend of the youth Narcissus who was in love with his won reflection. [Q300, Freud, 1917d, p. 139]
  • The ego is a great reservoir from which the libido that is destined for objects flows out and into which it flows back from those objects. Object-libido was at first ego-libido can be transformed back into ego-libido. For complete health it is essential that the libido should not lose this full mobility. As an illustration of this state of things we may think of an amoeba, whose viscous substance puts out pseudopodia, elongations into which the substance of the body extends but which can be retracted at any time so that the form of protoplasmic mass is restored. [Q301, Freud, 1917d, p. 139]
  • For this mind is not a simple thing; on the contrary, it is a hierarchy of superordinated and subordinated agencies, a labyrinth of impulses striving independently of one another towards action, corresponding with the multiplicity of instincts and of relations with the external world, may of which are antagonistic to one another and incompatible. For proper functioning it is necessary that the highest of these agencies should have knowledge of all that is going forward and that its will should penetrate everywhere, so as to exert its influence. And in fact the ego feels secure both as to the completeness and trustworthiness of the reports it receives and as to the openness of the channels through which it enforces its commands. [Q302, Freud, 1917d, p.141]
  • Even if you are not ill, who can tell all that is stirring in your mind of which you know nothing or are falsely informed? You behave like an absolute ruler who is content with the information supplied him by his highest officials and never goes among the people to hear their voice. Turn your eyes inward, look into your own depths, learn first to know yourself! [Q303, Freud, 1917d, p. 143]
  • It is thus that psycho-analysis has sought to educate the ego. But these two discoveries – that the life of our sexual [impulses] cannot be wholly tamed, and that mental processes are in themselves unconscious and only reach the ego and come under its control through incomplete and untrustworthy perceptions – these two discoveries amount to a statement that the ego is not master in its own house. Together they represent the third blow to man’s self-love, what I may call the psychological one. No wonder, then, that the ego does not look favourably upon psycho-analysis and obstinately refuses to believe in it. [Q304, Freud, 1917d, p. 143b]
  • Man’s archaic heritage forms the nucleus of the unconscious mind: and whatever part of that heritage has to be left behind in the advance to later phases of development, because it is unserviceable or incompatible with what is new and harmful to it, falls a victim to the process of repression. [Q305, Freud, 1917d, p. 204]

Standard Edition, Volume 18. Beyond the Pleasure Principle, Group Psychology & Other Works. 1920-1922.

  • In taking that course into account in our consideration of the mental processes which are the subject of our study, we are introducing an ‘economic’ point of view into our work; and if, in describing those processes, we try to estimate this ‘economic’ factor in addition to the ‘topographical’ and ‘dynamic’ ones, we shall, I think, be giving the most complete description of them of which we can at present conceive, and one which deserves to be called ‘metapsychological’. [Q306, Freud, 1920, p. 7]
  • The mental apparatus endeavours to keep the quantity of excitation present in it as low as possible or at least to keep it constant… Moreover, a more detailed discussion will show that the tendency which we thus attribute to the mental apparatus is subsumed as a special case under Fechner’s principle of the ‘tendency towards stability’. [Q307, Freud, 1920, p. 9]
  • Another occasion of the release of unpleasure, which occurs with no less regularity, is to be found in the conflicts and dissentions that take place in the mental apparatus while the ego is passing through its development into more highly composite organisations. Almost all the energy with which the apparatus is filled arises from its innate instinctual impulses. But these are not all allowed the same phases of development. In the course of things it happens again and again that individual impulses or parts of impulses turn out to be incompatible in their aims or demands with the remaining ones, which are able to combine into the inclusive unity of the ego. The former are then split off from this unity by the process of repression, held back at lower levels of psychical development and cut off, to begin with, from the possibility of satisfaction. [Q308, Freud, 1920, p.11]
  • It is certain that much of the ego is unconscious. [Q309, Freud, 1920, p. 19]
  • Protection against stimuli is an almost more important function for the living organism than reception of stimuli. The protective shield is supplied with its own store of energy and must above all endeavour to preserve the special modes of transformation of energy operating in it against the effects threatened by the enormous energies at work in the external world – effects which tend towards a levelling out of them and hence towards destruction. The main purpose of the reception of stimuli is to discover the direction and nature of the external stimuli; and for that it is enough to take small specimens of the external world, to sample it in small quantities. In highly developed organisms the receptive cortical layer of the former vesicle has long been withdrawn into the depths of the interior of the body, though portions of it have been left behind on the surface immediately beneath the general shield against stimuli. These are the sense organs, which consist essentially of apparatus for the reception of certain specific effects of stimulation, but which also include special arrangements for further protection against excessive amounts of stimulation and for excluding unsuitable kinds of stimuli. It is characteristic of them that they only deal with very small quantities of external stimulation and only take in samples of the external world. They may perhaps be compared with feelers which are all the time making tentative advances towards the external world and then drawing back from it. [Q310, Freud, 1920, p. 27-28]
  • We have learnt that unconscious mental processes are in themselves ‘timeless’. This means in the first place that they are not ordered temporally, that time does not change them in any way and that the idea of time cannot be applied to them. These are negative characteristics which can only be clearly understood if a comparison is made with conscious mental processes. On the other hand, our abstract idea of time seems to be wholly derived form the method of working of the perceptual system and to correspond to a perception on its own. [Q311, Freud, 1920, p. 28b]
  • A particular way is adopted of dealing with any internal excitations which produce too great an increase of unpleasure: there is a tendency to treat them as though they were acting, not from the inside but from the outside, so that it may be possible to bring the shield against stimuli into operation as a means of defence against them. This is the origin of projection, which is destined to play such a large part in the causation of pathological processes. [Q312, Freud, 1920, p. 29]
  • We describe as ‘traumatic’ any excitations from outside which are powerful enough to break through the protective shield. It seems to me that the concept of trauma necessarily implies a connection of this kind with a breach in an otherwise efficacious barrier against stimuli. [Q313, Freud, 1920, p. 29]
  • We infer that a system which is itself highly activated is capable of taking up an additional stream of fresh inflowing energy and of converting it into quiescent energy, that is of binding it psychically. The higher the system’s own quiescent energy, the greater seems to be its binding force; conversely, therefore, the lower the activation, the less capacity will it have for taking up inflowing energy. [Q314, Freud, 1920, p. 30]
  • The indefiniteness of all our discussions on what we describe as metapsychology is of course due to the fact that we know nothing of the nature of the excitatory process that takes place in the elements of the psychical systems, and that we do not feel justified in framing any hypothesis on the subject. We are consequently operating all the time with a large unknown factor, which we are obliged to carry over into every new formula. It may be reasonably supposed that this excitatory process can be carried out with energies that vary quantitatively; it may also seem probable that it has more than one quality (in the nature of amplitude, for instance). As a new factor we have taken into consideration Breuer’s hypothesis that charges of energy occur in two forms; so that we have distinguish between two kinds of activations of the psychical systems or their elements – a freely flowing activation that presses on towards discharge and a quiescent activation. We may perhaps suspect that the binding of the energy that streams into the mental apparatus consists in its change from a freely flowing into a quiescent state. [Q315, Freud, 1920, p. 31]
  • The fact that the cortical layer which receives stimuli is without any protective shield against excitations from within must have as its result that these latter transmissions of stimulus have a preponderance in economic importance and often occasion economic disturbances comparable with traumatic neuroses. The most abundant sources of this internal excitation are what are described as the organism’s drives – the representatives of all the forces originating in the interior of the body and transmitted to the mental apparatus – at once the most important and the most obscure element of psychological research. It will perhaps not be thought too rash to suppose that the impulses arising from the drives do not belong to the type of bound nervous processes but of freely mobile processes which press towards discharge. The best part of what we know of these processes is derived from our study of the dream-work… In the unconscious, energy can easily be transferred, displaced and condensed. [Q316, Freud, 1920, p. 34]
  • I described the type of process found in the unconscious as the ‘primary’ psychical process, in contradistinction to the secondary process which is the one obtaining in our normal waking life. Since all instinctual impulses have the unconscious systems as their point of impact, it is hardly an innovation to say that they obey the primary process. Again, it is easy to identify the primary psychical process with Breuer’s freely mobile activity and the secondary process with changes in his bound or tonic activity. [Q317, Freud, 1920, p.34]
  • It may be presumed too that when people unfamiliar with analysis feel an obscure fear – a dread of rousing something that, so they feel, is better left sleeping – what they are afraid of at bottom is the emergence of [a] compulsion with its hint of possession by some ‘daemonic’ power. [Q318, Freud, 1920, p. 36]
  • It seems that a drive is an urge inherent in organic life to restore an earlier state of things which the living entity has been obliged to abandon under the pressure of external disturbing forces; that is, it is a kind of organic elasticity, or to put it another way, the expression of the inertia inherent in organic life. [Q319, Freud, 1920, p. 36]
  • Advancing more cautiously, psycho-analysis observed the regularity with which libido is withdrawn from the object and directed on to the ego (the process of introversion); and, by studying the libidinal development of children in its earliest phases came to the conclusion that the ego is the true and original reservoir of libido and it is only from this reservoir that libido is extended on to objects. [Q320, Freud, 1920, p. 52]
  • We have found that one of the earliest and most important functions of the mental apparatus is to bind the instinctual impulses which impinge on it, to replace the primary process prevailing in them by the secondary process and convert their freely mobile energy into a mainly quiescent (tonic) activity. [Q321, Freud, 1920, p. 62]
  • This raises the question whether feelings of pleasure and unpleasure can be produced equally from bound and from unbound excitatory processes. And there seems to be no doubt whatever that the unbound or primary processes give rise to far more intense feelings in both directions than the bound or secondary ones… In any case, whatever it is that causes the appearance of feelings of pleasure and unpleasure in processes of excitation must be present in the secondary process just as it is in the primary one. [Q322, Freud, 1920, p. 63]
  • On previous occasions we have been driven to the hypothesis that some such agency develops in our ego which may cut itself off from the rest of the ego and come into conflict with it. We have called it the ‘ego ideal’ and by way of functions we have ascribed to it self-observation, the moral conscience, the censorship in dreams, and the chief influence in repression. We have said that it is heir to the original narcissism in which the childish ego enjoyed self-sufficiency; it gradually gathers up from the influences of the environment the demands which that environment makes upon the ego and which the ego cannot always rise to; so that a man, when he cannot be satisfied with his ego itself, may nevertheless be able to find satisfaction in the ego-ideal which has been differentiated out of the ego. In delusions of observation, as we have further shown, the disintegration of this agency has become patent, and has thus revealed its origin in the influence of superior powers and above all of the parents. [Q323, Freud, 1920, p. 110]
  • Speech owes its importance to its aptitude for mutual understanding in the herd, and upon it the identification of the individuals with one another largely rests. [Q324, Freud, 1920, p. 118]
  • In the course of our development we have effected a separation of our mental existence into a coherent ego and into an unconscious and repressed portion which is left outside of it. [Q325, Freud, 1920, p. 131]
  • The sense of guilt (as well as the sense of inferiority) can also be understood as an expression of tension between the ego and the ego ideal. [Q326, Freud, 1920, p. 131b]
  • To this day psycho-analysis is looked upon as one savouring of mysticism… But if we look closer, difficulties begin to emerge… Analysts are at bottom incorrigible mechanists and materialists, even though they seek to avoid robbing the mind and spirit of their still unrecognisable characteristics. So too, they embark on the investigation of occult phenomena only because they expect in that way finally to exclude the [wishful thinking] of mankind from material reality [i.e., from science]. [Q327, Freud, 1921, p. 179]
  • The neuroses are the expression of conflicts between the ego and such of the sexual impulses as seem to the ego incompatible with its integrity or with its ethical standards. Since these impulse are not ego-syntonic, the ego has repressed them: that is to say, it has withdrawn its interest from them and has shut them off from becoming conscious. [Q328, Freud, 1922, p. 246]
  • The ego itself came to be regarded as a reservoir of what was described as narcissistic libido, from which the libidinal energy of objects flowed out and into which they could be once more withdrawn… The narcissistic disorders (dementia praecox, paranoia, melancholia) are characterised by a withdrawal of the libido from objects and they are therefore scarcely assessable to analytic therapy. [Q329, Freud, 1922, p. 249]
  • The pathogenic process in dementia praecox is the withdrawal of the libido from objects and its introduction into the ego, while the clamorous symptoms of the ideas arise from the vain struggles of the libido to find a pathway back to objects. [Q330, Freud, 1922, p. 257]
  • The ego is to be regarded as a great reservoir of libido from which libido is sent out to objects and which is always ready to absorb libido flowing back from [Q331, Freud, 1922, p. 257b]
  • For that reason I think it advisable, when establishing a distinction between the different modes of thought-activity, not to utilise the relation to consciousness in the first instance, and to designate the day-dream… as freely wandering or fantastic thinking, in opposition to intentionally directed reflection. [Q332, Freud, 1921, p. 272]

Standard Edition, Volume 19. The Ego and the Id and Other Works. 1923-1925.


  • To most people who have been educated in philosophy the idea of anything psychical which is not also conscious is so inconceivable that it seems to them absurd and refutable simply by logic. I believe this is only because they have never studied the relevant phenomena of hypnosis and dreams, which – quite apart from pathological manifestations – necessitate this view. Their psychology of consciousness is incapable of solving the problems of dreams and hypnosis. [Q333, Freud, 1923, p. 13]
  • In each individual there is a coherent organisation of mental processes; and we call this his ego. It is to this ego that consciousness is attached; the ego controls the approaches to motility – that is, to the discharge of excitation into the external world. [Q334, Freud, 1923, p. 17]
  • We have come upon something in the ego itself which is also unconscious, which behaves exactly like the repressed – that is, which produces powerful effects without itself being conscious and which requires special work before it can be made conscious. [Q335, Freud, 1923, p. 17]
  • We have said that consciousness is the surface of the mental apparatus; that is, we have ascribed it as a function to a system [the perceptual system] which is spatially the first one reached from the external world – and spatially not only in the functional sense but on this occasion also in the sense of anatomical dissection. [Q336, Freud, 1923, p. 19]
  • Thinking in pictures [fantasy] is only a very incomplete form of becoming conscious. In some way, too, it stands nearer to unconscious processes than does thinking in words, and it is unquestionably older than the latter, both ontogenetically and phylogenetically. [Q337, Freud, 1923, p. 21]
  • Whereas the relation of external perceptions to the ego is quite perspicuous, that of internal perceptions to the ego requires special investigation. It gives rise once more to a doubt whether we are really right in referring the whole of consciousness to the single superficial perceptual system. [Q338, Freud, 1923, p. 21b]
  • We shall now look upon an individual as a psychical id, unknown and unconscious, upon whose surface rests the ego… The ego is not sharply separated from the id; its lower portion merges into it. [Q339, Freud, 1923, p. 24]
  • It is easy to see that the ego is that part of the id which has been modified by the direct influence of the external world through the medium of the perceptual system; in a sense it is an extension of the surface differentiation. Moreover, the ego seeks to bring the influence of the external world to bear upon the id and its tendencies… For the ego, perception plays the part which in the id falls to drive. The ego represents what may be called reason and common sense, in contrast to the id, which contains the passions. [Q340, Freud, 1923, p. 25]
  • Thus, in its relation to the id [the ego] is like a man on horseback, who has to hold in check the superior strength of the horse… Often a rider, if he is not to be parted from his horse, is obliged to guide it where it wants to go; so in the same way the ego is in the habit of transforming the id’s will into action as if it were its own. [Q341, Freud, 1923, p. 25]
  • The ego is first and foremost a bodily ego. [Q342, Freud, 1923, p. 26]
  • If we are to come back once more to our scale of values, we shall have to say that not only what is lowest but also what is highest in the ego can be unconscious. [Q343, Freud, 1923, p. 27]
  • If we consider once more the origin of the super-ego as we have described it, we shall recognise that it is the outcome of two highly important factors, once biological and the other of a historical nature: namely, the lengthy duration in man of his childhood helplessness and dependence, and the fact of his Oedipus complex, the repression of which we have shown to be connected with the interruption of libidinal development by the latency period and so with the diphasic onset of man’s sexual life. According to one psycho-analytic hypothesis, the last-mentioned phenomenon, which seems to be peculiar to man, is a heritage of the cultural development necessitated by the glacial epoch. We see, then, that the differentiation of the super-ego from the ego is no matter of chance; it represents the most important characteristics of the development both of the individual and of the species, indeed, by giving permanent expression to the influence of the parents it perpetuates the existence of the factors to which it owes its origin. [Q344, Freud, 1923, p. 35]
  • The ego-ideal is therefore heir to the Oedipus complex and this it is also the expression of the most powerful impulses and most important libidinal vicissitudes of the id. By setting up this ego ideal, the ego has mastered the Oedipus complex and at the same time placed itself in subjection to the id. Whereas the ego is essentially the representative of the external world, of reality, the super-ego stands in contrast to it as the representative of the internal world, of the id. [Q345, Freud, 1923, p. 36]
  • Through the forming of the ideal, what biology and the vicissitudes of the human species have created in the id and left behind in it is taken by the ego and re-experienced in relation to itself as an individual. Owing to the way in which the ego-ideal is formed, it has the most abundant links with the phylogenetic acquisition of each individual – this archaic heritage. What has belonged to the lowest part of the mental life of each of us in changed, through the formation of the ideal, into what is highest in the human mind by our scale of values. It would be in vain, however, to attempt to localise the ego ideal. Even in the sense in which we have localised the ego, or to work it into any of the analogies with the help of which we have tried to picture the relation between the ego and the id. [Q346, Freud, 1923, p. 36-37]
  • The differentiation between ego and id must be attributed not only to primitive man but even to much simpler organisms, for it is the inevitable expression of the influence of the external world. [Q347, Freud, 1923, p. 38]
  • Reflection at once shows us that no external vicissitudes can be experienced or undergone by the id, except by way of the ego, which is the representative of the external world to the id. Nevertheless it is not possible to speak of direct inheritance in the ego. It is here that the gulf between an actual individual and the concept of a species becomes evident. Moreover, one must not take the difference between ego and id in too hard-and-fast a sense, nor forget that the ego is a specially differentiated part of the id. The experiences of the ego seem at first to be lost for inheritance; but, when they have been repeated often enough and with sufficient strength in many individuals in successive generations, they transform themselves, so to say, into experiences of the id, the impressions of which are preserved by heredity. Thus in the id, which is capable of being inherited, are harboured residues of the existences of countless egos; and, when the ego forms its super-ego out of the id, it may perhaps only be reviving shapes of former egos and be bringing them to resurrection. [Q348, Freud, 1923, p. 38]
  • The way in which the super-ego came into being explains how it is that the early conflicts of the ego with the object-investments of the id can be continued in conflicts with their heir, the super-ego. If the ego has not succeeded in properly mastering the Oedipus complex, the energetic activation of the latter, springing from the id, will come into operation once more in the reaction-formation of the ego-ideal. The abundant communication between the ideal and these Ucs instinctual impulses solves the puzzle of how it is that the ideal itself can to a great extent remain unconscious and inaccessible to the ego. The struggle which once raged in the deepest strata of the mind, and was not brought to an end by rapid sublimation and identification, is now continued in a higher region, like the Battle of the Huns in Kaulbach’s painting. [Q349, Freud, 1923, p. 38-39]
  • We have already concluded that the ego is especially under the influence of perception, and that, speaking broadly, perceptions may be said to have the same significance for the ego as drives have for the id. [Q350, Freud, 1923, p. 40]
  • The ego deals with the first object-investments of the id (and certainly later ones too) by taking over the libido from them into itself and binding it to the alteration of the ego. [Q351, Freud, 1923, p. 46]
  • At the very beginning, all the libido is accumulated in the id, while the ego is still in process of formation or is still feeble. The id sends part of this libido out into erotic object-investments, whereupon the ego, now grown stronger, tries to get hold of this object-libido and to force itself on the id as a love-object. The narcissism of the ego is thus a secondary one, which has been withdrawn from objects. [Q352, Freud, 1923, p. 46b]
  • If it is true that Fechner’s principle of constancy governs life. [Q353, Freud, 1923, p. 47]
  • The feelings of inferiority so well known in neurotics are presumably not far removed from it. In two very familiar maladies the sense of guilt is over-strongly conscious; in them the ego ideal displays particular severity and often rages against the ego in a cruel fashion. [Q354, Freud, 1923, p. 51]
  • In certain forms of obsessional neurosis the sense of guilt in over-noisy but cannot justify itself to the ego. [Q355, Freud, 1923, p. 51b]
  • By virtue of [the ego’s] relation to the perceptual system it gives mental processes an order in time and submits them to reality-testing. By interposing processes of thinking, it secures a postponement of motor discharges and controls the access to motility. [Q356, Freud, 1923, p. 55]
  • All the experiences of life that originate from without enrich the ego; the id, however, is its second external world, which it strives to bring into subjection to itself. It withdraws libido from the id and transforms the object-investments of the id into ego structures. With the aid of the super-ego, in a manner that is still obscure to us, it draws upon the experiences of past ages stored in the id. [Q357, Freud, 1923, p. 55b]
  • There are two paths by which the contents of the id can penetrate into the ego. The one is direct, the other leads by way of the ego ideal; which of these two paths they take may, for some mental activities, be of decisive importance. The ego develops from perceiving impulses to controlling them, from obeying impulses to inhibiting them. [Q358, Freud, 1923, p. 56]
  • The id, to which we finally come back, has no means of showing the ego either love or hate. It cannot say what it wants; it has achieved no unified will. [Q359, Freud, 1923, p. 59]
  • But this ego developed out of the id, it forms with it a single biological unit, it is only a specially modified peripheral portion of it, and it is subject to the influences and obeys the suggestions that arise from the id. For any vital purpose, a separation of the ego from the id would be a hopeless undertaking. [Q360, Freud, 1925, p. 133]
  • Conscience is no doubt a reaction formation against the evil that is perceived in the id. [Q361, Freud, 1925, p. 134]
  • In undertaking the repression, the ego is at bottom following the commands of its super-ego – commands which, in their turn, originate from influences in the external world that have found representation in the super-ego. The fact remains that the ego has taken sides with those powers, that in it their demands have more strength than the instinctual demands of the id, and that the ego is the power which sets repression in motion against the portions of the id concerned and which fortifies the repression by means of the [inhibitory force] of resistance. The ego has come into conflict with the id in the service of the super-ego. [Q362, Freud, 1924, p. 150]
  • Normally, the external world governs the ego in two ways: firstly, by current, present perceptions which are always renewable, and secondly by the store of memories of earlier perceptions which, in the shape of an ‘internal world’, form a possession of the ego and a constituent part of it. [Q363, Freud, 1924, p. 150b]
  • Delusion is found like a patch over the place where originally a rent had appeared in the ego’s relation to the external world. [Q364, Freud, 1924, p. 151]
  • The pathogenic effect depends on whether, in a conflictual tension of this kind, the ego remains true to its dependence on the external world and attempts to silence the id or whether it lets itself by overcome by the id and thus torn away from reality. [Q365, Freud, 1924, p. 151b]
  • It will be remembered that we have taken the view that the principle which governs all mental processes is a special case of Fechner’s ‘tendency towards stability’, and have accordingly attributed to the mental apparatus the purpose of reducing to nothing, or at least of keeping as low as possible, the sums of excitation which flow in upon it. Barbara Low has suggested the name of ‘Nirvana principle’ for this supposed tendency, and we have accepted the term. [Q366, Freud, 1924b, p. 159]
  • The super-ego is as much a representative of the id as of the external world. It came into being through the introjection into the ego of the first objects of the id’s libidinal impulses – namely, the two parents. [Q367, Freud, 1924b, p. 167]
  • I have recently indicated as one of the features which differentiate a neurosis from a psychosis the fact that in a neurosis the ego, in its dependence of reality, suppresses a piece of the id (of instinctual life), whereas in a psychosis, the same ego, is the service of the id, withdraws from a piece of reality. [Q368, Freud, 1924c]
  • The fact that, in so many forms and cases of psychosis… the paramnesias, the delusions and the hallucinations that occur are of a most distressing character and are bound up with the generation of anxiety – this fact is without doubt a sign that the whole process of remodelling is carried through against the forces which oppose it violently. [Q369, Freud, 1924c]
  • The sharp distinction between neurosis and psychosis, however, is weakened by the circumstance that in neurosis, too, there is no lack of attempts to replace a disagreeable reality by one which is more in keeping with the subject’s wishes. This is made possible by the existence of a world of fantasy, of a domain which became separated from the real external world at the time of the introduction of the reality principle. This domain has since been kept free from the demands of the exigencies of life, like a kind of reservation. [Q370, Freud, 1924c]
  • It can hardly be doubted that the world of fantasy plays the same part in psychosis and that there too it is the storehouse from which the materials or the patterns for building the new reality are derived. [Q371, Freud, 1924c]
  • I have recently proposed of dividing the mental apparatus into an ego, turned towards the external world and equipped with consciousness, and an unconscious id, dominated by its instinctual needs, then psycho-analysis is to be described as a psychology of the id (and of its effects on the ego). [Q372, Freud, 1924d]
  • The other sort of decision made by the function of judgement – as to the real existence of something of which there is a presentation (reality-testing) – is a concern of the definitive reality-ego… It is now no longer a question of whether what has been perceived (a thing) shall be taken into the ego or not, but of whether something which is in the ego as a presentation can be rediscovered in perception (reality) as well. [Q373, Freud, 1924d]
  • Judging is the intellectual action which decides the choice of motor action, which puts an end to the postponement due to thought and which leads over from thinking to acting. [Q374, Freud, 1925b, p. 238]
  • For on our hypothesis, perception is not a purely passive process. The ego periodically sends out small amounts of energy into the perceptual system by means of which it samples the external stimuli and then after every such tentative advance it draws back again. [Q375, Freud, 1925b, p. 238b]
  • This view of negation fits in very well with the fact that in analysis we never discover a ‘no’ in the unconscious and that recognition of the unconscious on the part of the ego is expressed in a negative formula. There is no stronger evidence that we have been successful in our effort to uncover the unconscious than when the patient reacts to it with the words ‘I didn’t think that’ or ‘I didn’t (ever) think of that’. [Q376, Freud, 1925b, p. 239]

Standard Edition, Volume 20. An Autobiographical Study, Inhibitions, Symptoms and Anxiety, Lay Analysis and Other Works. 1925-1926.


  • The dividing of the conscious and the unconscious into various psychical systems – then psychoanalysis was no longer an auxiliary science in the field of psychopathology, it was rather the starting point if a new and deeper science of the mind which would be equally indispensable for the understanding of the normal. Its postulates and findings could be carried over to other regions of the mental happening; a path lay open to it that led far a field, into spheres of universal interest. [Q377, Freud, 1925c, p.47]
  • There followed form this fact the concept (of fundamental importance to libido theory) of a state in which the subject’s libido filled his own ego and had that for its object. This state could be called narcissism or self-love. A moment’s reflection showed that this state never completely ceases. All through the subject’s life his ego remains the great reservoir of libido, from which object-investments are sent out and into which the libido can stream back again from the objects. Thus narcissistic libido is constantly being transformed into object-libido and vice versa. [Q378, Freud, 1925c, p. 56]
  • I was always open to the ideas of G.T. Fechner and have followed that thinker upon many points. [Q379, Freud, 1925c, p. 59]
  • It seems to me that the ego obtains this influence in virtue of its intimate connections with the perceptual system – connections which, as we know, constitute its essence and provide the basis of its differentiation from the id. The function of this system, which we have called the perceptual system is bound up with the phenomenon of consciousness. [Q380, Freud, 1926, p. 92]
  • Just as the ego controls the path to action in regard to the external world, so it controls access to consciousness. [Q381, Freud, 1926, p. 95]
  • We know well enough how little light science has so far been able to throw on the problems that surround us. But however much ado the philosophers make, they cannot alter the situation. Only patient, persevering research, in which everything is subordinated to the one requirement for certainty, can gradually bring about change. The benighted traveller may sing aloud in the dark to deny his own fears; but for all that, he will not see an inch further in front of his nose. [Q382, Freud, 1926, p. 96]
  • We were justified, I think, in dividing the ego from the id, for there are certain considerations which necessitate that step. On the other hand the ego is identical with the id and is merely a specially differentiated part of it. If we think of this part by itself in contradistinction to the whole, or if a real split has occurred between the two, the weakness of the ego becomes apparent. But if the ego remains bound up with the id and indistinguishable from it, then it displays its strength. [Q383, Freud, 1926, p. 97]
  • In repression the decisive fact is that the ego is an organisation and the id is not. The ego is indeed the organised portion of the id. [Q384, Freud, 1926, p. 97b]
  • The ego is an organisation. It is based on the maintenance of free intercourse and of the possibility of reciprocal influence between all its parts. Its desexualised energy still shows traces of its origin in its impulsion to bind together and unify, and this necessity to synthesise grows stronger in proportion as the strength of the ego increases. It is therefore only natural that the ego should try to proven symptoms from remaining isolated and alien by using every possible method to bind them to itself in one way or another; and to incorporate them into its organisation by means of those bonds. [Q385, Freud, 1926, p. 98]
  • It is always the ego’s attitude of anxiety which is the primary thing and which sets repression going. [Q386, Freud, 1926, p. 109]
  • But even a normal person uses concentration to keep away not only what is irrelevant or unimportant but above all, what is unsuitable because it is contradictory. [Q387, Freud, 1926, p. 121]
  • Anxiety is an affective state and as such can, of course, only be felt by the ego. The id cannot have anxiety as the ego can; for it is not an organisation and cannot make a judgment about situations of danger. [Q388, Freud, 1926, p. 140]
  • This is inevitable from the nature of repression, which, is fundamentally an attempt at flight. The repressed is now, as it were, an outlaw; it is excluded from the great organisation of the ego and is subject only to the laws which govern the realm of the unconscious. [Q389, Freud, 1926, 153]
  • This has led us to suppose that something momentous must have occurred in the vicissitudes of the human species [events related to the glacial epoch] which has left behind this interruption in the sexual development of the individual as a historical precipitate. [Q390, Freud, 1926, p. 155]
  • In view of the dangers of external reality, the ego is obliged to guard against certain instinctual impulses in the id and to treat them as dangers. But it cannot protect itself from internal instinctual dangers as effectively as it can from some piece of reality that is not part of itself. Intimately bound up with the id as it is, it can only fend off an instinctual danger by restricting its own organisation and by acquiescing in the formation of symptoms in exchange for having impaired the impulse. If the rejected impulse renews its attack, the ego is overtaken by all those difficulties which are known as neurotic ailments. [Q391, Freud, 1926, p. 156]
  • We recognise is human beings a mental organisation which is interpolated between their sensory stimuli and the perception of their somatic needs on the one hand and their motor acts on the other, and which mediates between them for a particular purpose. We call this organisation their ‘Ich’ [‘ego’; literally, ‘I’]… Besides this ‘I’, we recognise another mental region, more extensive, more imposing and more obscure than the ‘I’, and this w call the ‘Es’ [‘id’; literally, ‘it’]. The relation between the two must be our immediate concern. [Q392, Freud, 1926b, p. 195]
  • I must ask you to picture the ego as a kind of façade of the id, as a frontage, like an external, cortical layer of it… We suppose that the ego is the layer of the mental apparatus (of the id) which has been modified by the influence of the external world (of reality). [Q393, Freud, 1926b, p. 195b]
  • The ego lies between reality and the id. [Q394, Freud, 1926b, p. 196]
  • The rules governing the course of mental acts are different in the ego and the id. [Q395, Freud, 1926b, p. 196b]
  • In the id there are no conflicts; contradictions and antithesis persist side by side unconcernedly. [Q396, Freud, 1926b, p. 196c]
  • The ego is an organisation characterised by a very remarkable trend towards unification, towards synthesis. This characteristic is lacking in the id. [Q397, Freud, 1926b, p. 196d]
  • Now, we believe that on the outermost surface of this ego there is a special agency directed immediately to the external world, a system … through the excitation of which alone the phenomenon that we call consciousness comes about. This organ can be equally excited from outside – thus receiving (with the help of the sense-organs) the stimuli from the external world – and from inside – thus becoming aware, first of the sensations in the id and then also of the processes in the ego. [Q398, Freud, 1926b, p. 198]
  • ‘Triebe’ [drive], a word for which we are envied by many modern languages. Well these drives fill the id: all the energy of the id, as we may put it briefly, originates from them. Nor have the forces of the ego any other origin; they are derived from those in the id. [Q399, Freud, 1926b, p. 200]
  • At that point the portion of the id which is directed towards the external world – the ego – begins to function. If all the driving force that sets the vehicle in motion is derived from the id, the ego, as it were, undertakes the steering, without which no goal can be reached. [Q400, Freud, 1926b, p. 201]
  • [The ego] carried on its activity in two directions. On the one hand, it observes the external world with the help of its sense-organ, the system of consciousness, so as to catch the favourable moment for harmless satisfaction; and on the other hand it influences the id, bridles its passion, induces its drives to postpone their satisfaction. [Q401, Freud, 1926b, p. 201b]
  • Yes, all will be well if the ego is in possession of its whole organisation and efficiency, if it has access to all parts of the id and can exercise its influence on them. For there is not natural opposition between ego and id; they belong together, and under healthy conditions cannot in practice be distinguished from each other. [Q402, Freud, 1926b, p. 201c]
  • The decisive repressions all take place in childhood. [Q403, Freud, 1926b, p. 202]
  • The super-ego occupies a special position between the ego and the id. It belongs to the ego and shares its high degree of psychological organisation; but it has a particularly intimate connection with the id. It is in fat a precipitate of the first object-investments of the id and is heir to the Oedipus complex after its demise. The super-ego can confront the ego and treat it like an object and it often treats it very harshly… The super-ego is the vehicle of the phenomenon that we call conscience. [Q404, Freud, 1926b, p. 223]
  • Illness is employed as an instrument for this ‘self-punishment’. And neurotics have to behave as though they were governed by a sense of guilt which, in order to be satisfied, needs to be punished by illness. [Q405, Freud, 1926b, p. 223b]
  • Under the extraordinary burden of this period of childhood – we have in a few years to cover the enormous developmental distance between stone-age primitive mend and the participants in contemporary civilisation, and, at the same time and in particular, we have to fend off the instinctual impulses of the early sexual period – under this burden, then. Our ego takes refuge in repression and lays itself open to a childhood neurosis, the precipitate of which it carried with it into maturity as a disposition to a later nervous illness. Everything now depends on how the growing organism is treated by fate. If life becomes too hard, if the gulf between impulsive claims and the demands of reality become too great, the ego may fail in its efforts to reconcile the two, and the more readily, the more it is inhibited by the disposition carried over by it from infancy. The process of repression is then repeated, the drives tear themselves away from the ego’s domination, find their substitutive satisfactions along the paths of regression, and the poor ego has become helplessly neurotic. [Q406, Freud, 1926b, p. 241-242]
  • But the relative feebleness of the ego [e.g., the childhood ego] is the decisive factor for the genesis of a neurosis, it must also be possible for a later physical illness to produce a neurosis provided that it can bring about an enfeeblement of the ego. And that, once again, is very frequently found. A physical disorder of this kind can affect the instinctual life of the id and increase the strength of the drives beyond a certain limit up to which the ego is capable of coping with them. The normal model of such process is perhaps the alteration in women caused by the disturbance of menstruation and the menopause. [Q407, Freud, 1926b, p. 242b]
  • As a depth psychology, a theory of the mental unconscious, [psychoanalysis] can become indispensable to all the sciences which are concerned with the evolution of human civilisation and its major institutions such as art, religion and the social order. [Q408, Freud, 1926b, p. 248]
  • I share the view that all those problems which relate to the connection between psychical phenomena and their organic, anatomical and chemical foundation can be approached only by those who have studied both, that is, by medical analysts. [Q409, Freud, 1926b, p. 257]
  • From the economic standpoint psycho-analysis supposes that the mental representatives of the drives have a charge of definite quantities of energy, and that it is the purpose of the mental apparatus to hinder any damming-up of these energies and to keep as low as possible the total amount of the excitations with which it is loaded. [Q410, Freud, 1926b, p. 266]
  • According to the most recent psycho-analytic views, the mental apparatus is composed of an ‘id’, which is the repository of the impulses, or an ego, which is the most superficial portion of the id and one which has been modified by the influence of the external world; and of a ‘super-ego’ which develops out of the id, dominates the ego and represents the inhibitions of drives that are characteristic of man. [Q411, Freud, 1926b, p. 266b]
  • It must not be supposed that these very general ideas are presuppositions upon which the work of psycho-analysis depends. On the contrary, they are its latest conclusions and are ‘open to revision’. Psycho-analysis is founded securely upon the observation of the facts of mental life and for that reason its theoretical superstructure is still incomplete and subject to constant alteration. [Q412, Freud, 1926b, p. 266c]

Standard Edition, Volume 21. The Future of an Illusion, Civilisation and its Discontents and Other Works. 1927-1931.


  • Normally, there is nothing of which we are more certain than the feeling of our self, of our own ego. This ego appears to us as something autonomous and unitary, marked off distinctly from everything else. Such an appearance is deceptive… on the contrary the ego is continued inwards, without any sharp delimitation into an unconscious mental entity which we designate as the id and for which it serves as a kind of façade. [Q413, Freud, 1930, p. 66]
  • Further reflection tells us that the adult’s ego feeling cannot have been the same from the beginning. It must have gone through a process of development. [Q414, Freud, 1930, p. 66]
  • Originally the ego includes everything, later is separates off an external world from itself. Our present ego-feeling is therefore a shrunken residue of a much more inclusive – indeed all-embracing – feeling which corresponded to a more intimate bond between the ego and the world about it… the ideational content appropriate to it would be precisely those of limitlessness and of a bond with the universe – the same ideas with which my friend elucidated the ‘oceanic’ feeling. [Q415, Freud, 1930, p. 68]
  • The ego itself is activated with libido, the ego, indeed, is the libido’s original home, and remains to some extent its headquarters. [Q416, Freud, 1930, p. 118]
  • The essential difference between neurosis and psychosis [is] that in the former, the ego, in the service of reality, suppresses a piece of the id, whereas in a psychosis it lets itself be induced by the id to detach itself from a piece of reality. [Q417, Freud, 1927, p. 155]
  • The cure too of such paranoic attacks would lie not so much in a resolution and correction of the delusional ideas as in a withdrawal from them of the energy which has been lent to them. The alternations between melancholia and mania, between a cruel suppression of the ego by the super-ego and a liberation of the ego after that pressure, suggests a shift of energy of this kind. [Q418, Freud, 1927, p. 165]

Standard Edition, Volume 22. New Introductory Lectures on Psycho-Analysis and Other Works. 1932-1936.


  • In psychosis, however, the turning away from reality is brought about in two kinds of way: either by the unconscious repressed becoming excessively strong so that it overwhelms the conscious which is attached to reality, or because reality has become so intolerably distressing that the threatened ego throws itself into the arms of the unconscious impulsive forces in a desperate revolt. [Q419, Freud, 1933, p. 16]
  • The processes which take place in the unconscious system… has shown us that they are quite other than what we know from our conscious thinking and are bound to appear to the latter preposterous and incorrect. [Q420, Freud, 1933, p. 17]
  • The ego can take itself as an object, can treat itself like other objects, can observe itself, criticise itself, and do Heaven knows what with itself. In this, one part of the ego is setting itself over against the rest [i.e., the super-ego over the ego]. So the ego can be split; it splits itself during a number of its functions – temporarily at least. Its parts can come together afterwards. [Q421, Freud, 1933, p. 58]
  • We perceive that we have no right to name the mental region that is foreign to the ego ‘the system Ucs’, since the characteristics of being unconscious is not restricted to it. Very well; we will no longer use the term ‘unconscious’ in the systematic sense and we will give what we have hitherto described a better name and one no longer open to misunderstanding. Following a verbal usage of Nietzsche’s and taking up a suggestion by Georg Groddeck, we will in future call it the ‘Es’ [i.e., ‘it’, the ‘id’]. [Q422, Freud, 1933, p. 72]
  • You will not expect me to have much to tell you that is new about the id apart from its new name. It is the dark, inaccessible part of our personality; what little we know of it we learnt from our study of dream-work and of the construction of neurotic symptoms and most of that is of a negative character and can be described only as a contrast to the ego. We approach the id with analogies: we call it a chaos, a cauldron full of seething excitations… It is filled with energy reaching it from the drives but it has no organisation, produces no collective will… The logical laws of thought do not apply in the id, and this is true above all of the law of contradiction. Contrary impulses exist side by side without cancelling each other out or diminishing each other: at the moment they may converge to form compromises under the dominating economic pressure towards the discharge of energy. [Q423, Freud, 1933, p. 73]
  • There is nothing in the id that could be compared with negation [i.e., a ‘no’]; and we perceive with surprise an exception to the philosophical theorem that space and time are necessary forms of our mental acts. There is nothing in the id that corresponds to the idea of time; there is o recognition of the passage of time, and – a thing that is most remarkable and awaits consideration in philosophical thought – no alteration in its mental processes is produced by the passage of time. Wishful impulses which have never passed beyond the id but impressions too which have been sunk into the id by repression, are virtually immortal; after the passage of decades they behave as though they had just occurred. They can only be recognised as belonging to the past, can only lose their importance and be deprived of the investment of energy, when they have been made conscious by the work of analysis. Again and again I have had the impression that we have made too little theoretical use of this fact, established beyond any doubt, of the inalterability by time of the repressed. [Q424, Freud, 1933, p. 74]
  • The id of course knows no judgement of value: no good and evil. [Q425, Freud, 1933, p. 74b]
  • It even seems that the energy of these impulses is in a state different from that in the other regions of the mind, far more mobile and capable of discharge. [Q426, Freud, 1933, p. 74c]
  • We can best arrive at the characteristics of the actual ego, in so far as it can be distinguished from the id and from the super-ego, by examining its relation to the outermost superficial portion of mental apparatus, which we describe as the perceptual system. This system is turned towards the external world, it is the medium for the perceptions arising thence, and during its functioning the phenomenon of consciousness arises in it. It is the sense-organ of the entire apparatus; moreover it is receptive not only to excitations from outside but also to those arising out of the interior of the mind. We need scarcely look for a justification of the view that the ego is that portion of the id which was modified by the proximity and influence of the external world, which is adapted for the reception of stimuli and as a protective shield against stimuli, comparable to the cortical layer by which a small piece of living substance is surrounded. The relation to the external world has become the decisive factor for the ego; it has taken on the task of representing the external world to the id. [Q427, Freud, 1933, p. 75]
  • The ego must observe the external world, must lay down an accurate picture of it on the memory traces of its perceptions, and by its exercise o the function of reality-testing, must put aside whatever in this picture of the external world is an addition derived from internal sources of excitation. The ego controls the approaches to motility under the id’s orders; but between a need and an action it has interposed a postponement in the form of the activity of thought, during which it makes use of the mnemic residues of experience. [Q428, Freud, 1933, p. 76]
  • The relation to time, which is so hard to describe, is also introduced into the ego by the perceptual system; it can scarcely be doubted that the mode of operation of that system is what provides the origin of the idea of time. But what distinguishes the ego from the id quite especially is a tendency to synthesis in its contents, to a combination and unification in its mental processes which are totally lacking in the id. When presently we come to deal with the impulses in mental life we shall, I hope, succeed in tracing this essential characteristic of the ego back to its source. It alone produces the high degree of organisation which the ego needs for its best achievements. The ego develops from perceiving the impulses to controlling them; but this last is only achieved by the representative of the impulses being allotted its proper place in a considerable assemblage, by its being taken up into a coherent context. To adopt a popular mode of speaking, we might say that the ego stands for reason and good sense while the id stands for the untamed passions. [Q429, Freud, 1933, p. 76]
  • The ego is after all only a portion of the id, a portion that has been expediently modified by the proximity of the external world with its threat of danger. [Q430, Freud, 1933, p. 77]
  • Thus, the ego, driven by the id, confined by the super-ego, repulsed by reality, struggles to master its economic task of bringing about harmony among the forces and influences working in and upon it; and we can understand how it is that so often we cannot suppress a cry: ‘Life is not easy!’ If the ego is obliged to admit its weakness, it breaks out in anxiety – realistic anxiety regarding the external world, moral anxiety regarding the super-ego and neurotic anxiety regarding the strength of the passions in the id. [Q431, Freud, 1933, p. 78]
  • The super-ego merges into the id; indeed, as heir to the Oedipus complex it has intimate relations with the id, it is more remote than the ego from the perceptual system. [Q432, Freud, 1933, p. 79]
  • It is easy to imagine too that certain mystical practices may succeed in upsetting the normal relations between the different regions of the mind, so that for instance, perception may be able to grasp happening in the depths of the ego and in the id which were otherwise inaccessible to it. [Q433, Freud, 1933, p. 80]
  • [The intention of psychoanalysis] is to strengthen the ego, to make it more independent of the super-ego, to widen its field of perception an enlarge its organisation, so that it can appropriate fresh portions of the id. Where id was, there ego shall be. It is a work of culture – not unlike the draining of the Zuider Zee. [Q434, Freud, 1933, p. 80b]
  • Thinking is an experimental action carried out with small amounts of energy. [Q435, Freud, 1933, p. 89]
  • The ego is the better organised part of the id, with its face turned towards reality. [Q436, Freud, 1933, p. 93]
  • An impulse then is distinguished from a stimulus by the fact that it arises from sources of stimulation within the body, that it operates as a constant force and that the subject cannot avoid it by flight, as is possible with an external stimulus. [Q437, Freud, 1933, p. 96]
  • The ego is always the main reservoir of libido from which libidinal investments of objects go out and into which they return again, while the major part of this libido remains permanently in the ego. Thus ego libido is constantly being changed into object libido and object libido into ego libido. [Q438, Freud, 1933, p. 103]

Standard Edition, Volume 23. Moses and Monotheism, An Outline of Psycho-Analysis and Other Works. 1937-1939.

  • The sexual life of human beings exhibits an efflorescence which comes to an end at about the firth year and it followed by what is known as the period of latency (till puberty)… [this] leads us to suppose that the human race is descended from a species of animal which reached sexual maturity in five years and rouses a suspicion that the postponement of sexual life and its diphasic onset are intimately connected with the history of hominisation. Human beings appear to be the only animal organisms with a latency period and sexual retardation of this kind. [Q439, Freud, 1939, p. 75]
  • We now distinguish in our mental life (which we regard as an apparatus compounded of several agencies, districts or provinces) one regions which we call the ego proper and another which we name the id. The id is the older of the two; the ego has developed out it, like a cortical layer, through the influence of the external world. It is in the id that all our primary impulses are at work, all the processes in the id take place unconsciously. [Q440, Freud, 1939, p. 96]
  • The psychical topography that I have developed here has nothing to do with the anatomy of the brain and actually only touches it at one point. What is unsatisfactory in this picture – and I am aware of it as clearly as anyone – is due to our complete ignorance of the dynamic nature of the mental processes. [Q441, Freud, 1939, p. 97]
  • But a fresh complication arises when we become aware of the probability that what may be operative in an individual’s psychical life may include not only what he has experienced himself but also things that were innately present in him at his birth, elements with a phylogenetic origin –an archaic heritage. [Q442, Freud, 1939, p. 98]
  • The immediate and most certain answer is that it consists in certain innate dispositions such as are characteristic of all living organisms: the capacity and tendency to enter particular lines of development and to react in a particular manner to certain excitations, impressions and stimuli. Since experience shows that there are distinctions in this respect between individuals of the human species, the archaic heritage must include these distinction; they represent what we recognise as the constitutional factor in the individual. [Q443, Freud, 1939, p. 98]
  • If any explanation at all is to be found of this instinctive life of animals, it can only be that they bring the experiences of their species with them into their own new existence – that is, that they have preserved memories of what was experienced by their ancestors. The position of the human animal would not at bottom be different… After this discussion I have no hesitation in declaring that men have always known (in this special way) that they once possessed a primal father and killed him. [Q444, Freud, 1939, p. 98b]
  • In our children, in adults who are neurotic, as well as in primitive peoples, we meet with the mental phenomenon which we describe as a belief in the ‘omnipotence of thoughts’. In our judgement this lies in an over-estimation of the influence which our mental acts can exercise in altering the external world. At bottom magic, the precursor of our technology, rests on this premise… The ‘omnipotence of thoughts’ was we suppose, an expression of the pride of mankind in the development of speech, which resulted in such an extraordinary advancement of intellectual activities. The new realm of intellectuality was opened up, in which ideas, memories, and inferences become decisive in contrast to the lower psychical activity which had direct perceptions by the sense-organs as its content. This was unquestionably one of the most important stages in the development of hominisation. [Q445, Freud, 1939, p. 113]
  • The oldest of these psychical provinces or agencies we give the name of id. It contains everything that is inherited, that is present at birth, that is laid down in the constitution – above all, therefore, the drives, which originate from the somatic organisation and which find a first psychical expression here in forms unknown to us. [Q446, Freud, 1940, p. 145]
  • Under the influence of the real external world around us, one portion of the id has undergone a special development. From what was originally a cortical layer, equipped with the organs for receiving stimuli and with arrangements for acting as a protective shield against stimuli, a special organisation has arisen which henceforth acts as an intermediary between the id and the external world. To this region of the mind we have given the name of ego. [Q447, Freud, 1940, p. 145b]
  • The ego has voluntary movement at its command. It has the task of self-preservation. As regards external events, it performs that task by becoming aware of stimuli, by storing up experiences about them (in the memory), by avoiding excessively strong stimuli (through flight), by dealing with moderate stimuli (through adaptation) and finally by learning to bring about expedient changes in the external world to its own advantage (through activity). As regards internal events, in relation to the id, it performs that task by gaining control over the demands of the drives, by devising whether they are to be allowed satisfaction, by postponing that satisfaction to times and circumstances favourable in the external world or by suppressing their excitation entirely. [Q448, Freud, 1940, p. 146]
  • The long period of childhood, during which the growing human being lives in dependence of his parents, leaves behind it as a precipitate the formation in his ego of a special agency in which this parental influence is prolonged. It has received the name of the super-ego. In so far as this super-ego is differentiated from the ego or is opposed to it, it constitutes a third power which the ego must take into account. [Q449, Freud, 1940, p. 146b]
  • The id and the super-ego have one thing in common: they both represent the influence of the past – the id the influence of heredity, the super-ego the influence , essentially of what is taken over from other people – whereas the ego is principally determined by the individual’s own experience, that is by accidental and contemporary events. [Q450, Freud, 1940, p. 147]
  • This general schematic picture of a psychical apparatus may be supposed to apply as well to the higher animals which resemble man mentally. A super-ego must be presumed to be present wherever, as is the case with man, there is a long period of dependence in childhood. [Q451, Freud, 1940, p. 147b]
  • The power of the id expresses the true purpose of the individual organism’s life. This consists in the satisfaction of its innate needs. No such purpose as that of keeping itself alive or of protecting itself from dangers by means of anxiety can be attributed to the id. That is the task of the ego. [Q452, Freud, 1940, p. 148]
  • The forces which we assume to exist behind the tensions caused by the needs of the id are called the drives. They represent the somatic demands upon the mind. [Q453, Freud, 1940, p. 148]
  • It is hard to say anything of the behaviour of the libido in the id and the super-ego. All that we know about it relates to the ego, in which at first the whole available quota of libido is stored up. We call this state absolute, primary narcissism. It lasts till the ego begins to invest the ideas of objects with libido, to transform narcissistic libido into object-libido. Throughout the whole of life the ego remains the great reservoir from which libidinal investments are sent out to objects and into which they are also once more withdrawn. [Q454, Freud, 1940, p. 150]
  • What come about in analytic treatment as a result of our efforts can also occur spontaneously: material which is ordinarily unconscious can transform itself into preconscious [i.e., consciously accessible] material and then become conscious – a thing that happens to a large extent in psychotic states. From this we infer that the maintenance of certain internal resistances is a sine qua non of normality. [Q455, Freud, 1940, p. 161]
  • The process of something becoming conscious is above all linked with the perceptions which our sense organs receive from the external world. From the topographical point of view, therefore, it is a phenomenon which take place in the outermost cortex of the ego. [Q456, Freud, 1940, p. 161b]
  • Internal processes in the ego may also acquire consciousness. This is the work of the function of speech which brings material in the ego into a firm connection with mnemic residues of visual but more particularly auditory perceptions. Thenceforward the perceptual periphery of the cortical layer can be excited to a much greater extent from inside as well, internal events such as passages of ideas and thought-processes can become conscious and a special device is called for in order to distinguish between the two possibilities – a device known as reality-testing. [Q457, Freud, 1940, p. 162]
  • The sole prevailing quality in the id is that of being unconscious. Id and unconscious are as intimately linked as ego and preconscious. [Q458, Freud, 1940, p. 163]
  • Originally, to be sure, everything was id; the ego was developed out of the id by the continual influence of the external world. In the course of this slow development certain of the contents of the id were transformed into the preconscious state and so taken into the ego, others of its contents remained in the id unchanged, as its scarcely accessible nucleus. [Q459, Freud, 1940, p. 163b]
  • During this development, however, the young and feeble ego put back into the unconscious state some of the material it has already taken in, dropped it and behaved in the same way to some fresh impressions which it might have taken in, so that these, having been rejected, could leave a trace only in the id. In consideration of its origin we speak of this latter portion of the id as the repressed. [Q460, Freud, 1940, p. 163c]
  • We seem to recognise that nervous or psychical energy occurs in two forms, one freely mobile and another, by comparison, bound; we speak of activations] and [hyperactivations] of psychical material, and even venture to suppose a [hyperactivation] brings about a kind of synthesis of different processes – a synthesis in the course of which free energy is transformed into bound energy… We hold firmly to the view that the distinction between the [primary] and the [secondary] state lies in dynamic relations of this kind, which would explain how it is that, whether spontaneously or with our assistance, the one can be changed into the other… We have found that processes in the unconscious or in the id obey different laws from those in the ego. We name these laws in their totality the primary process, in contrast to the secondary process which governs the course of events in the ego.”[Q461, Freud, 1940, p. 164]
  • An investigation of normal, stable states, in which the frontiers of the ego are safeguarded against the id… would teach us little. The only thing that can help us are states of conflict and uproar, where the contents of the unconscious id have a prospect of forcing their way into the ego and into consciousness… It is only under these conditions that we can make such observations as will confirm or correct our statements about the two partners [Q462, Freud, 1940, p. 165]
  • Now our nightly sleep is precisely a state of this sort, and for that reason psychical activity during sleep, which we perceive as dreams, is our most favourable object of study. [Q463, Freud, 1940, p. 165b]
  • The study of the dream-work teaches us by an excellent example the way in which unconscious material from the id (originally unconscious and repressed unconscious alike) forces its way into the ego. [Q464, Freud, 1940, 165c]
  • Dreams bring up recollections which the dreamer has forgotten, which are inaccessible to him when he is awake. [Q465, Freud, 1940, p. 166]
  • Since the waking ego governs motility, that function is paralysed in sleep, and accordingly a good part of the inhibitions imposed on the unconscious id become superfluous. The withdrawal or reduction of these [inhibitory forces] thus allow the id what is now a harmless amount of liberty. [Q466, Freud, 1940, p. 166b]
  • Memory very often reproduces in dreams impressions from the dreamer’s early childhood. [Q467, Freud, 1940, p. 166c]
  • Dreams bring to light material which cannot have originated either from the dreamer’s adult life or from his forgotten childhood. We are obliged to regard it as part of the archaic heritage which a child brings with him into the world, before any experience of his own, influenced by the experience of his ancestors. We find the counterpart of this phylogenetic material in the earliest human legends and in surviving customs. Thus dreams constitute a source of human prehistory which is not to be despised. [Q468, Freud, 1940, p. 167]
  • But what makes dreams so invaluable in giving us insight is the circumstance that, when the unconscious material makes its way into the ego, it brings its own modes of working along with it. [Q469, Freud, 1940, p. 167b]
  • Our theory infers that in the unconscious id the energy is in a freely mobile state and that the id sets more store by the possibility of discharging quantities of excitation than by any other consideration; and our theory makes use of these two peculiarities in defining the character of the primary process we have attributed to the id. [Q470, Freud, 1940, p. 168]
  • The governing rules of logic carry no weight in the unconscious; it might be referred to as the Realm of the Illogical. Urges with contrary aims exist side by side in the unconscious without any need arising for an adjustment between them. [Q471, Freud, 1940, p. 168-169]
  • Something that is a satisfaction for the unconscious id may for that very reason be a cause of anxiety for the ego. [Q472, Freud, 1940, p. 171]
  • Experience has shown that the unconscious mechanisms which we have come to know from our study of the dream-work and which gave us the explanation of the formation of dreams also help us to understand the puzzling symptoms which attract our interest to neuroses and psychoses. [Q473, Freud, 1940, p. 171b]
  • A dream, then, is a psychosis, with all the absurdities, delusions and illusions of a psychosis. [Q474, Freud, 1940, p. 172]
  • The necessary precondition of the pathological states under discussion can only be a relative or absolute weakening of the ego which makes the fulfilment of its tasks impossible. The severest demand on the ego is probably the keeping down of the impulsive claims of the id, to accomplish which it is obliged to maintain large expenditures of energy on [inhibition]. [Q475, Freud, 1940, p. 172b]
  • We may suspect that in the economic conflicts which arise at this point, the id and the super-ego often make common cause against the hard-pressed ego which tries to cling to reality in order to retain its normal state. If the other two become too strong, they succeed in loosening and altering the ego’s organisation so that its proper relation to reality is disturbed or even brought to an end. We have seen it happen in dreaming: when the ego is detached from the reality of the external world, it slips down under the influence of the internal world into psychosis. [Q476, Freud, 1940, p. 172-173]
  • The [unconscious] has a natural upward drive and desires nothing better than to press forward across its settled frontiers into the ego and so to consciousness. [Q477, Freud, 1940, p. 179]
  • But here we are concerned with therapy only in so far as it works by psychological means; and for the time being we have no other. The future may teach us to exercise a direct influence, by means of particular chemical substances, on the amounts of energy and their distribution in the mental apparatus. It may be that there are other still undreamt-of possibilities of therapy. But for the moment we have nothing better at our disposal than the technique of psycho-analysis, and for that reason, in spite of its limitations, it should not be despised. [Q478, Freud, 1940, p. 180]
  • The core of our being, then, is formed by the obscure id, which has no direct communication with the external world and is accessible even to our own knowledge only through the medium of another agency. Within the id the organic drives [Q479, Freud, 1940, p. 197]
  • But immediate and unheeding satisfaction of the drives such as the id demands would often lead to perilous conflicts with the external world and to extinction. The id knows no solicitude about ensuring survival and no anxiety; or it would perhaps be more correct to say that, though it can generate the sensory elements of anxiety, it cannot make use of them. The processes which are possible in and between the assumed psychical elements in the id (the primary process) differ widely from those which are familiar to us through conscious perception in our intellectual and emotional life; nor are they subject to the critical restrictions of logic, which repudiates some of these processes as invalid and seeks to under them. [Q480, Freud, 1940, p. 198]
  • The ego has been developed out of the id’s cortical layer, which through being adapted to the reception and exclusion of stimuli, is in direct contact with the external world (reality). Starting from conscious perception is has subjected to its influence ever larger regions and deeper strata of the id. [Q481, Freud, 1940, p. 198-199]
  • The ego makes use of sensations of anxiety as a signal to give warning of dangers that threaten its integrity. Since memory traces can become conscious just as perceptions do, especially through association with residues of speech, the possibility arises of a confusion which would lead to a mistaking of reality. The ego guards itself against this possibility by the institution of reality-testing, which is allowed to fall into abeyance in dreams. [Q482, Freud, 1940, p. 199b]
  • [The ego’s] psychological function consists in raising the passage of [energy] in the id to a higher dynamic level (perhaps by transforming freely mobile energy into bound energy). [Q483, Freud, 1940, p. 199c]
  • Thus the ego is fighting on two fronts: it has to defend against an external world which threatens it with annihilation as well as against an internal world that makes excessive demands. [Q484, Freud, 1940, p. 200]
  • The ego owes its origin as well as the most important of its acquired characteristics to its relation to the real external world. We are thus prepared to assume that the ego’s pathological states, in which it most approximates once again to the id, are founded on a cessation or slackening of the relation to the external world… The precipitating cause of an outbreak of psychosis is either that reality has become intolerably painful or that the drives have become extraordinarily intensified – both of which, in view of the rival claims on the ego made by the id and the external world, must lead to the same result. The problem of psychoses would be simple and perspicuous if the ego’s detachment from reality could be carried through completely. But that seems to happen rarely or perhaps never. Even is a state so far removed from the reality of the external world as one of hallucinatory confusion, one learns from patients after their recovery that at the time in some corner of their mind (as they put it) there was a normal person hidden, who, like a detached spectator, watched the hubbub of illness go past him. [Q485, Freud, 1940, p. 201]
  • At about [the age of five] an important change [takes place in the ego]. A portion of the external world has, at least partially, been abandoned as an object and has instead, by identification, been taken into the ego and this become an integral part of the internal world. This new psychical agency continues to carry on the functions which have hitherto been performed by the people in the external world: it observes the ego, gives it orders, judges it and threatens it with punishments, exactly like the parents whose place it has taken. [Q486, Freud, 1940, p. 205]
  • The super-ego continues to play the part of the external world for the ego, although it has become a portion of the internal world. [Q487, Freud, 1940, p. 206]
  • Twice in the course of individual development certain drives are considerably reinforced: at puberty, and, in women, at the menopause. We are not in the least surprised if a person who was not neurotic before becomes so at these times. [Q488, Freud, 1940, p. 226]
  • The repressions behave like dams against the pressure of water. [Q489, Freud, 1940, p. 226]
  • Repressions depend absolutely and entirely on the relative strength of the forces involved and they cannot hold out against an increase in the strength of the drives. [Q489, Freud, 1940, p. 227]
  • When we speak of an ‘archaic heritage’, we are usually thinking only of the id. [Q490, Freud, 1940, p. 240]
  • In certain analyses… [patients] have had lively recollections called up in them – which they themselves have described as ‘ultra-clear’. [Q491, Freud, 1937, p. 266]
  • The transposing of material from a forgotten past on to the present or on to an expectation of the future in indeed a habitual occurrence in neurotics no less than psychotics. Often enough, when a neurotic is led by an anxiety-state to expect the occurrence of some terrible event, he is in fact merely under the influence of a repressed memory (which is seeking to enter consciousness but cannot become conscious) that something which was at the time terrifying did really happen. I believe that we should gain a great deal of valuable knowledge from work of this kind upon psychotics even if it led to no therapeutic success. [Q492, Freud, 1937, p. 268]
  • In consequence of the special character of our discoveries, our scientific work in psychology will consist in translating unconscious processes into conscious ones, and thus filling the gaps in conscious perception. [Q493, Freud, 1940b, p. 286]

Note: with regards our use of terms, for accessibility we have chosen to refer to the problematic German term “besetzung” (“filling” in English but referred to as “cathexis” in the standard edition) as “activated”, “activation”, “activity”, “investment” and in some cases simply “energy” – also “anticathexis” is translated as “inhibition” or “inhibitory action”. Our rationale for this is to simplify the terms and make them more accessible, especially to those who might be put-off by overly-complicated neologisms which were not Freud’s own. Similarly, we have chosen to use the term “ego” instead of “preconscious”. The motivation for this again is to improve the reader’s familiarity with the system being described. For the same reasons we also sometimes refer to “the unconscious” or “system Ucs” as “the id” and we refer to “instinct” as “drive” or “impulse” which are arguably truer translations of the German “triebe”. Finally, we refer to the “system Cs (Pcpt)” with the simpler “perceptual system” and relate this to the DMN’s anticorrelated networks; principally, the attention and salience systems.

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