1. The intensities of the individual ideas become capable of discharge in their entirety, and, proceeding from one conception to the other, they thus form single presentations endowed with marked intensity. Through the repeated recurrence of this process the intensity of an entire train of ideas may ultimately be gathered in a single presentation element. This is the principle of compression or condensation. It is condensation that is mainly responsible for the strange impression of the dream, for we know of nothing analogous to it in the normal psychic life accessible to consciousness. We find here, also, presentations which possess great psychic significance as junctions or as end-results of whole chains of thought; but this validity does not manifest itself in any character conspicuous enough for internal perception; hence, what has been presented in it does not become in any way more intensive. In the process of condensation the entire psychic connection becomes transformed into the intensity of the presentation content. It is the same as in a book where we space or print in heavy type any word upon which particular stress is laid for the understanding of the text. In speech the same word would be pronounced loudly and deliberately and with emphasis. The first comparison leads us at once to an example taken from the chapter on "The Dream-Work" (trimethylamine in the dream of Irma's injection). Historians of art call our attention to the fact that the most ancient historical sculptures follow a similar principle in expressing the rank of the persons represented by the size of the statue. The king is made two or three times as large as his retinue or the vanquished enemy. A piece of art, however, from the Roman period makes use of more subtle means to accomplish the same purpose. The figure of the emperor is placed in the center in a firmly erect posture; special care is bestowed on the proper modelling of his figure; his enemies are seen cowering at his feet; but he is no longer represented a giant among dwarfs. However, the bowing of the subordinate to his superior in our own days is only an echo of that ancient principle of representation.

The direction taken by the condensations of the dream is prescribed on the one hand by the true foreconscious relations of the dream thoughts, an the other hand by the attraction of the visual reminiscences in the unconscious. The success of the condensation work produces those intensities which are required for penetration into the perception systems.

2. Through this free transferability of the intensities, moreover, and in the service of condensation, intermediary presentations—compromises, as it were—are formed (cf. the numerous examples). This, likewise, is something unheard of in the normal presentation course, where it is above all a question of selection and retention of the "proper" presentation element. On the other hand, composite and compromise formations occur with extraordinary frequency when we are trying to find the linguistic expression for foreconscious thoughts; these are considered "slips of the tongue."

3. The presentations which transfer their intensities to one another are very loosely connected, and are joined together by such forms of association as are spurned in our serious thought and are utilized in the production of the effect of wit only. Among these we particularly find associations of the sound and consonance types.

4. Contradictory thoughts do not strive to eliminate one another, but remain side by side. They often unite to produce condensation as if no contradiction existed, or they form compromises for which we should never forgive our thoughts, but which we frequently approve of in our actions.

These are some of the most conspicuous abnormal processes to which the thoughts which have previously been rationally formed are subjected in the course of the dream-work. As the main feature of these processes we recognize the high importance attached to the fact of rendering the occupation energy mobile and capable of discharge; the content and the actual significance of the psychic elements, to which these energies adhere, become a matter of secondary importance. One might possibly think that the condensation and compromise formation is effected only in the service of regression, when occasion arises for changing thoughts into pictures. But the analysis and—still more distinctly—the synthesis of dreams which lack regression toward pictures, e.g. the dream "Autodidasker—Conversation with Court-Councilor N.," present the same processes of displacement and condensation as the others.

Hence we cannot refuse to acknowledge that the two kinds of essentially different psychic processes participate in the formation of the dream; one forms perfectly correct dream thoughts which are equivalent to normal thoughts, while the other treats these ideas in a highly surprising and incorrect manner. The latter process we have already set apart as the dream-work proper. What have we now to advance concerning this latter psychic process?

We should be unable to answer this question here if we had not penetrated considerably into the psychology of the neuroses and especially of hysteria. From this we learn that the same incorrect psychic processes—as well as others that have not been enumerated—control the formation of hysterical symptoms. In hysteria, too, we at once find a series of perfectly correct thoughts equivalent to our conscious thoughts, of whose existence, however, in this form we can learn nothing and which we can only subsequently reconstruct. If they have forced their way anywhere to our perception, we discover from the analysis of the symptom formed that these normal thoughts have been subjected to abnormal treatment and have been transformed into the symptom by means of condensation and compromise formation, through superficial associations, under cover of contradictions, and eventually over the road of regression. In view of the complete identity found between the peculiarities of the dream-work and of the psychic activity forming the psychoneurotic symptoms, we shall feel justified in transferring to the dream the conclusions urged upon us by hysteria.

From the theory of hysteria we borrow the proposition that such an abnormal psychic elaboration of a normal train of thought takes place only when the latter has been used for the transference of an unconscious wish which dates from the infantile life and is in a state of repression. In accordance with this proposition we have construed the theory of the dream on the assumption that the actuating dream-wish invariably originates in the unconscious, which, as we ourselves have admitted, cannot be universally demonstrated though it cannot be refuted. But in order to explain the real meaning of the term repression, which we have employed so freely, we shall be obliged to make some further addition to our psychological construction.

We have above elaborated the fiction of a primitive psychic apparatus, whose work is regulated by the efforts to avoid accumulation of excitement and as far as possible to maintain itself free from excitement. For this reason it was constructed after the plan of a reflex apparatus; the motility, originally the path for the inner bodily change, formed a discharging path standing at its disposal. We subsequently discussed the psychic results of a feeling of gratification, and we might at the same time have introduced the second assumption, viz. that accumulation of excitement—following certain modalities that do not concern us—is perceived as pain and sets the apparatus in motion in order to reproduce a feeling of gratification in which the diminution of the excitement is perceived as pleasure. Such a current in the apparatus which emanates from pain and strives for pleasure we call a wish. We have said that nothing but a wish is capable of setting the apparatus in motion, and that the discharge of excitement in the apparatus is regulated automatically by the perception of pleasure and pain. The first wish must have been an hallucinatory occupation of the memory for gratification. But this hallucination, unless it were maintained to the point of exhaustion, proved incapable of bringing about a cessation of the desire and consequently of securing the pleasure connected with gratification.