He was the first to emphasize the significance of unconscious processes in normal and neurotic behaviour, and was the founder of psychoanalysis as both a theory of personality and a therapeutic practice. He proposed the existence of an unconscious element in the mind which influences consciousness, and of conflicts in it between various sets of forces. Freud also stated the importance of a child’s semi-consciousness of sex as a factor in mental development; his theory of the sexual origin of neuroses aroused great controversy