Optimal Distinctiveness Theory : A Framework for Social Identity , Social Cognition , and Intergroup Relations

Optimal distinctiveness theory [Brewer, M. B. (1991). The social self: on being the same and different at the same time. Personality & Social Psychology Bulletin, 17(5), 475–482] proposes that individuals have two fundamental and competing human needs—the need for inclusion and the need for differentiation—that can be met by membership in moderately inclusive (optimally distinct) groups. In this chapter, the optimal distinctiveness model and its origins are summarized, and theoretical extensions and empirical tests of the model are discussed. In particular, the empirical review summarizes the model’s consequences for social identification, social cognition, and intergroup relations. The evidence strongly supports the notion that the needs for inclusion and differentiation influence self-categorization resulting in a curvilinear relation between group inclusiveness and group identification. The existing evidence also indicates that the two needs influence perceptions and judgments of the self and others and the nature of intragroup and intergroup relations. The chapter concludes by discussing the interplay of the needs for inclusion and differentiation across levels of the self and how the needs for inclusion and differentiation influence which level of self (individual or collective) is motivationally primary.