Definition
Prejudice is a preformed and typically negative attitude toward a person or group, based on category membership rather than individual evidence. Social psychologists distinguish three linked components: a cognitive element (stereotypes — generalized beliefs about a group), an affective element (emotional reactions such as fear, contempt, or disgust), and a behavioral element (discrimination — differential treatment expressed in action).
The word comes from the Latin praejudicium, meaning "judgment in advance." A prejudiced view is not necessarily a strongly held one; it can operate automatically and outside conscious awareness, as research on implicit bias has shown. Modern definitions also recognize that prejudice can favor as well as disfavor groups — in-group favoritism is a structurally similar phenomenon.
Why it matters
How it works
Several converging theories explain why prejudice arises. Social identity theory, developed by Henri Tajfel, holds that people derive part of their self-concept from group memberships and tend to favor their in-group over out-groups even when group boundaries are arbitrary. Realistic conflict theory attributes prejudice to competition over scarce resources between groups. System justification theory proposes that members of both advantaged and disadvantaged groups can develop attitudes that legitimize existing hierarchies. Authoritarian personality research, pioneered by Adorno and colleagues, links prejudice to a constellation of traits including conventionalism, submission to authority, and aggression toward out-groups.
The contact hypothesis, proposed by Gordon Allport in 1954, identified conditions under which intergroup contact reduces prejudice: equal status between groups, common goals, intergroup cooperation, and institutional support. Subsequent meta-analyses across hundreds of studies have confirmed that well-designed contact does reliably reduce prejudice, with effects that generalize beyond the specific individuals encountered. But contact under unequal status, competitive pressure, or without sustained engagement can entrench prejudice rather than soften it. This is why structural interventions — changing the rules that govern intergroup interaction — often matter more than attempts to change minds one person at a time.