An unjustifiable generalization, based on a few striking examples, is contained in the statement that every dream admits of two kinds of interpretation: one of the kind we have described, the so-called “psycho-analytic” interpretation, and the other the so-called “anagogic,” which disregards the instinctive tendencies and aims at a representation of the higher mental functions (H. Silberer); there are dreams of this kind, but you will seek in vain to extend this conception to include even a majority of dreams. After all you have heard, the statement that all dreams are to be interpreted bisexually, as a combination of two tendencies which may be called male and female (A. Adler), will seem to you quite incomprehensible. Here again, single dreams of this sort do of course occur and later on you may learn that their structure is similar to that of certain hysterical symptoms. I mention all these discoveries of new general characteristics of dreams in order to warn you against them, or at least to leave you in no doubt about my own opinion of them. 4. At one time the objective value of research into dreams seemed to be discredited by the fact that patients treated analytically appeared to suit the content of their dreams to the favourite theories of their doctors, one class dreaming mainly of sexual impulses, and another of impulses for mastery, others again even of rebirth (W. Stekel). The force of this observation is weakened by the reflection that people dreamed dreams before there was any such thing as psycho-analytic treatment to influence their dreams and that the patients undergoing treatment nowadays also used to dream before they began it. The actual fact in this supposedly new observation is soon shown to be self-evident and of no consequence for the theory of dreams. The residue from the previous day which gives rise to dreams is a residue from the great interests of waking life. If the physician’s words and the stimuli which he gives have become of importance to the patient they then enter into whatever constitutes the residue and can act as mental stimuli for dream-formation, just like other interests of affective value roused on the preceding day which have not subsided; they operate in the same way as bodily stimuli which affect the sleeper during sleep. Like these other factors inciting dreams, the trains of thought roused by the physician can appear in the manifest dream-content or be revealed in the latent thoughts. We know indeed that dreams can be experimentally produced, or, to speak more accurately, a part of the dream-material can be thus introduced into the dream. In influencing his patients thus the analyst plays a part no different from that of an experimenter, like Mourly Void, who placed in certain positions the limbs of the person upon whom he experimented.