Let us compare the dream of Napoleon I- who, incidentally, was an excellent sleeper- with that of the sleepy student, who was awakened by his landlady with the reminder that he had to go to the hospital, and who thereupon dreamt himself into a bed in the hospital, and then slept on, the underlying reasoning being as follows: If I am already in the hospital, I needn't get up to go there. This is obviously a convenience- dream; the sleeper frankly admits to himself his motive in dreaming; but he thereby reveals one of the secrets of dreaming in general. In a certain sense, all dreams are convenience-dreams; they serve the purpose of continuing to sleep instead of waking. The dream is the guardian of sleep, not its disturber. In another place we shall have occasion to justify this conception in respect to the psychic factors that make for waking; but we can already demonstrate its applicability to the objective external stimuli. Either the mind does not concern itself at all with the causes of sensations during sleep, if it is able to carry this attitude through as against the intensity of the stimuli, and their significance, of which it is well aware; or it employs the dream to deny these stimuli; or, thirdly, if it is obliged to recognize the stimuli, it seeks that interpretation of them which will represent the actual sensation as a component of a desired situation which is compatible with sleep. The actual sensation is woven into the dream in order to deprive it of its reality. Napoleon is permitted to go on sleeping; it is only a dream-memory of the thunder of the guns at Arcole which is trying to disturb him. * -

* The two sources from which I know of this dream do not entirely agree as to its content. -

The wish to sleep, to which the conscious ego has adjusted itself, and which (together with the dream- censorship and the "secondary elaboration" to be mentioned later) represents the ego's contribution to the dream, must thus always be taken into account as a motive of dream-formation, and every successful dream is a fulfilment of this wish. The relation of this general, constantly present, and unvarying sleep- wish to the other wishes of which now one and now another is fulfilled by the dreamcontent, will be the subject of later consideration. In the wish to sleep we have discovered a motive capable of supplying the deficiency in the theory of Strumpell and Wundt, and of explaining the perversity and capriciousness of the interpretation of the external stimulus. The correct interpretation, of which the sleeping mind is perfectly capable, would involve active interest, and would require the sleeper to wake; hence, of those interpretations which are possible at all, only such are admitted as are acceptable to the dictatorial censorship of the sleep-wish. The logic of dream situations would run, for example: "It is the nightingale, and not the lark." For if it is the lark, love's night is at an end. From among the interpretations of the stimulus which are thus admissible, that one is selected which can secure the best connection with the wish- impulses that are lying in wait in the mind. Thus everything is definitely determined, and nothing is left to caprice. The misinterpretation is not an illusion, but- if you will- an excuse. Here again, as in substitution by displacement in the service of the dream-censorship, we have an act of deflection of the normal psychic procedure.

If the external nerve-stimuli and the inner bodily stimuli are sufficiently intense to compel psychic attention, they represent- that is, if they result in dreaming at all, and not in waking- a fixed point for dream-formation, a nucleus in the dream-material, for which an appropriate wish-fulfilment is sought, just as (see above) mediating ideas between two psychical dream-stimuli are sought. To this extent it is true of a number of dreams that the somatic element dictates the dream-content. In this extreme case even a wish that is not actually present may be aroused for the purpose of dream-formation. But the dream cannot do otherwise than represent a wish in some situation as fulfilled; it is, as it were, confronted with the task of discovering what wish can be represented as fulfilled by the given sensation. Even if this given material is of a painful or disagreeable character, yet it is not unserviceable for the purposes of dream-formation. The psychic life has at its disposal even wishes whose fulfilment evokes displeasure, which seems a contradiction, but becomes perfectly intelligible if we take into account the presence of two sorts of psychic instance and the censorship that subsists between them.

In the psychic life there exist, as we have seen, repressed wishes, which belong to the first system, and to whose fulfilment the second system is opposed. We do not mean this in a historic sense- that such wishes have once existed and have subsequently been destroyed. The doctrine of repression, which we need in the study of psychoneuroses, asserts that such repressed wishes still exist, but simultaneously