Sigmund Freud's psychoanalytic theory argues that human behavior results from the interaction of the id, ego, and superego. The id operates on the pleasure principle, the ego mediates reality, and the superego internalizes societal values. Freud believed all human actions stem from life and death instincts. Psychoanalysis aims to make the unconscious conscious by identifying repressed urges and enabling patients to deal with them realistically.