Carl Gustav Jung was a Swiss psychiatrist and psychotherapist who founded analytical psychology. Jung proposed and developed the concepts of the extroverted and the introverted personality, archetypes, and the collective unconscious. His work has been influential in psychiatry and in the study of religion, literature, and related fields. The central concept of analytical psychology is individuation ‚Äì the psychological process of integrating the opposites, including the conscious with the unconscious, while still maintaining their relative autonomy. Jung considered individuation to be the central process of human development.