People derive self-worth from group membership and denigrate outsiders to protect it

Evidence

Moreover, with respect to collective identity, people obtain a sense of self-worth from the groups to which they belong, so that self and group identity are linked. Individuals therefore seek to belong to groups that are evaluated more positively than other groups, and will denigrate other groups and limit their opportunities in order to obtain this outcome. — , Rudman, Laurie A - On the Nature of…, 1495

Categorization

• DEFINE: Core premise of Social Identity Theory stated compactly.
• XREF: connects to: Deflationary self-protection by individuals is zero-sum against everyone else — Mark Blyth, Austerity: The History of a Dangerous…, 47; Mere group membership suffices to trigger self-esteem-linked favoritism. — Anthony G. Greenwald and Mahzarin R. Banaji, Implicit Social Cognition: Attitudes,…, 126