Jung, yoong, Carl Gustav (1875-1961), was a Swiss psychiatrist and psychologist who developed the field of analytical psychology. His teachings extended beyond psychology and influenced other fields, including anthropology, philosophy, and theology. Jung challenged many of the theories proposed by the famous Austrian physician Sigmund Freud, who had developed the method of therapy called psychoanalysis. However, both Jung and Freud stressed the effects of unconscious ideas on human behavior.