Freud began to build up his conception of personality development by the gradual universalization of phenomena which he encountered in actual clinical work, and which he first described in relatively modest and restricted terms. He began his original psychological contributions by stressing the rôle of sexuality in the etiology of certain neuroses. He found that all sorts of pathological conditions and developmental abnormalities were apparently due to some shortcoming in sexual integration. This emphasis upon sexual adjustment as a necessary prerequisite of healthy adulthood met with so much opposition that Freud’s energies were taken up with defending and elaborating his position. Now the sexual function is essentially a species function and stresses the biological uniformities of man at the expense of individuality. A topic like “personality development” requires a comprehensive theory of individuality, and this Freud did not develop until the split with Adler, who insisted upon the rôle of a drive toward individualization and who denied that the much neglected “ego instincts” of Freud were enough to support a comprehensive theory. The story of Freud’s neurosis-sexuality-personality theories begins with his earliest independent psychological contributions. Many clinicians before Freud had been abundantly impressed by the frequency with which sexual troubles seemed to beget “nervous” troubles. In his hypnotic work, Freud was especially struck by the frequency with which specifically sexual episodes were involved in the pathogenic experiences. Freud now proceeded to generalize about the sexual element in neurosis, and announced that neurosis was a function of deviated sexual life. Freud armed in defense of his generalization with two new weapons. The first was his experience in letting his patients talk it out and in treating most of their productions as symbolic of something else. He acquired facility in interpreting what other people took literally as being a disguised representation of something else. So, when Freud was confronted with cases which were not manifestly sexual, he felt able to treat the non-sexual elements as symbolic representations of sexuality and to justify himself by claiming that his more intensive research procedure supplied him with the sustaining facts. Needless to say, those who had not themselves experienced the shift in standpoint which Freud had achieved were alienated by his seeming arbitrariness. Freud’s second reliance was on an inclusive theory of sexuality. Undaunted by the ridicule heaped upon his sexual theory of the neurosis, he carried the war into enemy territory by extending the whole concept of sexuality backward from puberty through the life of the growing child to infancy.