I have dwelt upon this historical example of the exaggerated development of mood complexes because, while well within the limits of normal life, it brings home to us the recognition of psychological facts which we all, more or less, have in common. But, more important than this, in certain abnormal conditions where the dissociation between systems of complexes becomes more exaggerated, mood, subject, chronological and other complexes, linked as each is with its own characteristic emotions and feelings—instincts and other innate dispositions—play a paramount part and dominate the personality. In the _hysterical personality_, in particular, there is more or less complete reversion to or a subconscious awakening of one or other such complex. Where the hysterical dissociation becomes so extreme as to eventuate in amnesia in one state for another the different systems of complexes are easily recognized as so many phases of _multiple personality_. But in so identifying the ideational content of phases of personality it should not be overlooked that intensive studies of multiple personality disclose the fact that the dissociation of one phase for another carries with it certain of the instincts innate in every organism. What I mean to say is, observation of psychopathological states has shown that instincts, such as play, hunger, anger, fear, love, disgust, the sexual instincts, etc., may be dissociated separately or in conjunction with complexes of ideas. In every case of multiple personality that I have had the opportunity to study each phase has been shorn of one or more of these inborn psycho-physiological dispositions and I believe this obtains in every true case. As a result certain sentiments and traits are lost while those that are retained stamp an individuality upon the phase. And as the conative forces of the retained instincts are not balanced and checked by the dissociated opposing instincts, the sentiments which they form and the emotional reactions to which they give rise stand out as dominating traits. Thus one phase may be characterized by pugnacity, self-assertion, and elation; another by submission, fear and tender feeling; and so on.