Sigmund Freud's theory of the human mind
id - the primitive and instinctive component of personality, cares only about themselves, and their wants and needs (JACK)
ego - the realistic, decision-making component, relies on the superego for good sense and morality, and tries to meet the desire of the id in a way that is socially acceptable - a balance of good and bad (RALPH)
superego - embodies selfless actions, stands by morality and judgements on right and wrong, and the ideals of civilisation taught by adults (PIGGY)