Unconscious processes of mind are a fact of life, both as phenomenon and as explanatory concept and were recognized before Freud. But it was Freud who not only put “the unconscious” on the map but also operationalized it in a new way—as a dynamic unconscious, laying down the foundation of a science of the unconscious, his Copernican revolution. The new science first provided a dual purpose method: investigating the emotional and ideational manifestations of disordered human behavior and psychological conflict and healing those disorders. In becoming a general psychoanalytic psychology, it played an important role in unraveling the dynamics of sexuality in the individual and society, literature and the arts, and in group dynamics in peace and war. The author emphasizes hitherto unacknowledged aspects: (1) The distinction between a theory of method and a theory of disorder; and (2) The role of interpersonal, or dyadic, dynamics in Freud's method, completing the largely monadic or intrap-ersonal focus in Freud. The author also discusses critiques of Freud's method both within and without psychonalysis.