is most characteristic for the dream. In this dilemma the majority of authors have developed a tendency to depreciate as much as possible the psychic factor in the excitations of dreams which is so difficult to approach. To be sure, they distinguish as a main division of dreams the nerve-exciting and the association dreams, and assert that the latter has its source exclusively in reproduction (Wundt,76 p. 365), but they cannot yet dismiss the doubt whether "they do not appear without being impelled by the psychical stimulus" (Volkelt,72 p. 127). The characteristic quality of the pure association dream is also found wanting. To quote Volkelt (p. 118): "In the association dreams proper we can no longer speak of such a firm nucleus. Here the loose grouping penetrates also into the centre of the dream. The ideation which is already set free from reason and intellect is here no longer held together by the more important psychical and mental stimuli, but is left to its own aimless shifting and complete confusion." Wundt, too, attempts to depreciate the psychic factor in the stimulation of dreams by declaring that the "phantasms of the dream certainly are unjustly regarded as pure hallucinations, and that probably most dream presentations are really illusions, inasmuch as they emanate from slight sensory impressions which are never extinguished during sleep" (p. 338, &c.). Weygandt75 agrees with this view, but generalises it. He asserts that "the first source of all dream presentations is a sensory stimulus to which reproductive associations are then joined" (p. 17). Tissié68 goes still further in repressing the psychic exciting sources (p. 183): "Les rêves d'origine absolument psychique n'existent pas"; and elsewhere (p. 6), "Les pensées de nos rêves nous viennent de dehors..."
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