The document discusses several theories of prejudice:
1) Frustration-aggression hypothesis argues that frustration leads to aggression, which is often displaced onto a scapegoat if the original source is unavailable or too powerful.
2) Adorno's authoritarian personality theory proposed that authoritarian child-rearing practices can lead to clusters of prejudices from childhood to adulthood, though situational factors are also important.
3) Social identity theory views prejudice as a way to maintain positive social identity and self-esteem by favoring the in-group over out-groups.