Freud believed human behavior is driven by the id, ego, and superego. The id operates on the pleasure principle seeking immediate gratification of desires. The ego uses reason and reality to satisfy the id within social norms. The superego incorporates moral values and causes guilt when one fails to act properly. Freud saw the id as the source of motivation, while the superego represses urges motivating good behavior. Childhood experiences shape the development of ego and superego as children learn acceptable behavior.