As a way of illuminating the crucial dilemma involved in creating a code of ethics for psychoanalysis—the tension between the psychoanalyst's responsibility to the needs of patients and his duty as a member of a civilized, organized society—the author explores the nature and effects of the instincts on the human personality and human behavior. Freud's paper “Totem and Taboo” is called on extensively as the source for Freudian and modern psychoanalytic understandings of the aggressive drive.