The author traces notions about unconscious mental processes to philosophers and psychologists preceding Freud. Leibnitz, Kant, and Wundt developed complex ideas about a cognitive unconscious, in which sensory data are actively and unconsciously organized (apperceived). Unlike the Freudian dynamic unconscious, the cognitive unconscious of these thinkers encounters no special forces driving its contents toward or away from consciousness. Yet the two concepts seem inextricably intertwined, in that motives for repression involve cognitive appraisal of unconscious mental contents. This is clear in the dream, in which unconscious cognitive appraisals of unconscious wishes are involved in the processes of dream formation and disguise. The motives for repression stem not only from these unconscious cognitive factors, but also from unconscious understanding of social constraints and socially-mediated constructs of experience.