Those authors who, like the influential philosopher Wundt, adopt a middle course do not fail to remark that in most dreams there is a co-operation of the somatic stimuli with the psychic instigators of the dream, the latter being either unknown or recognised as day interests. We shall learn later that the riddle of the dream formation can be solved by the disclosure of an unsuspected psychic source of excitement. For the present we shall not be surprised at the over-estimation of those stimuli for the formation of the dream which do not originate from psychic life. It is not merely because they alone can easily be found and even confirmed by experiment, but the somatic conception of the origin of dreams thoroughly corresponds to the mode of thinking in vogue nowadays in psychiatry. Indeed, the mastery of the brain over the organism is particularly emphasized; but everything that might prove an independence of the psychic life from the demonstrable organic changes, or a spontaneity in its manifestations, is alarming to the psychiatrist nowadays, as if an acknowledgment of the same were bound to bring back the times of natural philosophy and the metaphysical conception of the psychic essence. The distrust of the psychiatrist has placed the psyche under a guardian, so to speak, and now demands that none of its feelings shall divulge any of its own faculties; but this attitude shows slight confidence in the stability of the causal concatenation which extends between the material and the psychic. Even where on investigation the psychic can be recognised as the primary course of a phenomenon, a more profound penetration will some day succeed in finding a continuation of the path to the organic determination of the psychic. But where the psychic must be taken as the terminus for our present knowledge, it should not be denied on that account.