A groundbreaking revision of the psychoanalytic theory of sexuality and its centrality to mental life, distinguishing between adult and infantile states of mind, and between infantile polymorphous and infantile perverse sexuality. Meltzer traces the history of the psychoanalytical theory of psychosexual development and clinical sexual psychopathology from Freud through Abraham, Klein, and Bion. Next, he presents his revision of the theory of psychosexual development, with particular emphasis on the role of the super-ego-ideal, and then views several dimensions of differentiation. Finally, some exploration into the implications and applications of this revised theory to other areas, such as politics, education, abortion, art, and law.