The Interpretation of Dreams by Sigmund Freud
4. Psychic sources of excitation

When considering the relation of dreams to waking life, and the provenance of the material of dreams, we learned that the earliest as well as the most recent investigators are agreed that men dream of what they do during the day, and of the things that interest them in the waking state. This interest, continued from waking life into sleep, is not only a psychic bond, joining the dream to life, but it is also a source of dreams whose importance must not be underestimated, and which, taken together with those stimuli which become active and of interest during sleep, suffices to explain the origin of all dream-images. Yet we have also heard the very contrary of this asserted; namely, that dreams bear the sleeper away from the interests of the day, and that in most cases we do not dream of things which have occupied our attention during the day until after they have lost, for our waking life, the stimulating force of belonging to the present. Hence in the analysis of dream-life we are reminded at every step that it is inadmissible to frame general rules without making provision for qualifications by introducing such terms as "frequently," "as a rule," "in most cases," and without being prepared to admit the validity of exceptions.

If interest during the waking state together with the internal and external stimuli that occur during sleep, sufficed to cover the whole aetiology of dreams, we should be in a position to give a satisfactory account of the origin of all the elements of a dream; the problem of the dream-sources would then be solved, leaving us only the task of discriminating between the part played by the psychic and that played by the somatic dream-stimuli in individual dreams. But as a matter of fact no such complete solution of a dream has ever been achieved in any case, and everyone who has attempted such a solution has found that components of the dream- and usually a great many of them- are left whose source he is unable to trace. The interests of the day as a psychic source of dreams are obviously not so influential as to justify the confident assertion that every dreamer continues the activities of his waking life in his dreams.

Other dream-sources of a psychic nature are not known. Hence, with the exception perhaps of the explanation of dreams given by Scherner, to which reference will be made later on, all the explanations found in the literature of the subject show a considerable hiatus whenever there is a question of tracing the images and ideas which are the most characteristic material of dreams. In this dilemma the majority of authors have developed a tendency to belittle as far as possible the share of the psychic factor, which is so difficult to determine, in the evocation of dreams. To be sure, they distinguish as major divisions the nerve-stimulus dream and the association-dream, and assert that the latter has its source exclusively in reproduction (Wundt, p. 365), but they cannot dismiss the doubt as to "whether they appear without any impulsion from organic stimuli" (Volkelt, p. 127). And even the characteristic quality of the pure association-dream disappears. To quote Volkelt (p. 118): "In the association-dream proper, there is no longer any question of such a stable nucleus. Here the loose grouping penetrates even to the very centre of the dream. The imaginative life, already released from the control of reason and intellect, is here no longer held together by the more important psychical and physical stimuli, but is left to its own uncontrolled and confused divagations." Wundt, too, attempts to belittle the psychic factor in the evocation of dreams by asserting that "the phantasms of the dream are perhaps unjustly regarded as pure hallucinations. Probably most dream-representations are really illusions, inasmuch as they emanate from the slight sensory impressions which are never extinguished during sleep" (p. 359, et seq.). Weygandt has adopted this view, and generalizes upon it. He asserts that "the most immediate causes of all dream-representations are sensory stimuli to which reproductive associations then attach themselves" (p. 17). Tissie goes still further in suppressing the psychic sources of excitation (p. 183): "Les reves d'origine absolument psychique n'existent pas"; * and elsewhere (p. 6), "Les pensees de nos reves nous viennent de dehors...." *(2)

* Dreams do not exist whose origin is totally psychic.

*(2) The thoughts of our dreams come from outside.

Those writers who, like the eminent philosopher Wundt, adopt a middle course, do not hesitate to assert that in most dreams there is a cooperation of the somatic stimuli and psychic stimuli which are either unknown or are identified with the interests of the day.

We shall learn later that the problem of dream-formation may be solved by the disclosure of an entirely unsuspected psychic source of excitation. In the meanwhile we shall not be surprised at the over-estimation of the influence of those stimuli which do not originate in the psychic life. It is not merely because they alone may easily be found, and even confirmed by experiment, but because the somatic conception of the origin of dreams entirely corresponds with the mode of thought prevalent in modern psychiatry. Here, it is true, the mastery of the brain over the organism is most emphatically stressed; but everything that might show that the psychic life is independent of demonstrable organic changes, or spontaneous in its manifestations, is alarming to the contemporary psychiatrist, as though such an admission must mean a return to the old-world natural philosophy and the metaphysical conception of the nature of the soul. The distrust of the psychiatrist has placed the psyche under tutelage, so to speak; it requires that none of the impulses of the psyche shall reveal an autonomous power. Yet this attitude merely betrays a lack of confidence in the stability of the causal concatenation between the physical and the psychic. Even where on investigation the psychic may be recognized as the primary cause of a phenomenon, a more profound comprehension of the subject will one day succeed in following up the path that leads to the organic basis of the psychic. But where the psychic must, in the present state of our knowledge, be accepted as the terminus, it need not on that account be disavowed.