c) _Personality and the social self._--The selections upon "Personality and the Social Self" bring together and compare the different definitions of the term. These definitions fall under three heads: (1) _The organism as personality:_ This is a biological statement, satisfactory as a definition only as preparatory to further analysis. (2) _Personality as a complex:_ Personality defined in terms of the unity of mental life is a conception that has grown up in the recent "individual psychology," so called. Personality includes, in this case, not only the memories of the individual and his stream of consciousness, but also the characteristic organization of mental complexes and trends which may be thought of as a supercomplex. The phenomena of double and multiple personalities occur when this unity becomes disorganized. Disorganization in releasing groups of complexes from control may even permit the formation of independent organizations. Morton Prince's book _The Dissociation of a Personality_ is a classic case study of multiple personality. The selections upon "The Natural Person versus the Social and Conventional Person" and "The Divided Self and the Moral Consciousness" indicate the more usual and less extreme conflicts of opposing sentiments and interests within the organization of personality. (3) _Personality as the rôle of the individual in the group:_ The word personality is derived from the Latin _persona_, a mask used by actors. The etymology of the term suggests that its meaning is to be found in the rôle of the individual in the social group. By usage, personality carries the implication of the social expression of behavior. Personality may then be defined as the sum and organization of those traits which determine the rôle of the individual in the group. The following is a classification of the characteristics of the person which affect his social status and efficiency: (a) physical traits, as physique, physiognomy, etc.; (b) temperament; (c) character; (d) social expression, as by facial expression, gesture, manner, speech, writing, etc.; (e) prestige, as by birth, past success, status, etc.; (f) the individual's conception of his rôle. The significance of these traits consists in the way in which they enter into the rôle of the individual in his social milieu. Chief among these may be considered the individual's conception of the part which he plays among his fellows. Cooley's discriminating description of "the looking-glass self" offers a picture of the process by which the person conceives himself in terms of the attitudes of others toward him.