We have already taken the first step in this direction in setting up the thesis that the dream activity is under a compulsion to elaborate all the dream stimuli which are simultaneously present into a unified whole (p. 151). We have seen that when two or more experiences capable of making an impression have been left over from the previous day, the wishes which result from them are united into one dream; similarly, that an impression possessing psychic value and the indifferent experiences of the previous day are united in the dream material, provided there are available connecting ideas between the two. Thus the dream appears to be a reaction to everything which is simultaneously present as actual in the sleeping mind. As far as we have hitherto analysed the dream material, we have discovered it to be a collection of psychic remnants and memory traces, which we were obliged to credit (on account of the preference shown for recent and infantile material) with a character of actuality, though the nature of this was not at the time determinable. Now it will not be difficult to foretell what will happen when new material in the form of sensations is added to these actualities of memory. These stimuli likewise derive importance for the dream because they are actual; they are united with the other psychic actualities in order to make up the material for dream formation. To express it differently, the stimuli which appear during sleep are worked over into the fulfilment of a wish, the other component parts of which are the remnants of daily experience with which we are familiar. This union, however, is not inevitable; we have heard that more than one sort of attitude towards bodily stimuli is possible during sleep. Wherever this union has been brought about, it has simply been possible to find for the dream content that kind of presentation material which will give representation to both classes of dream sources, the somatic as well as the psychic. The essential nature of the dream is not changed by this addition of somatic material to the psychic sources of the dream; it remains the fulfilment of a wish without reference to the way in which its expression is determined by the actual material.