Shared knowledge that others hold the same stereotypes grants social permission to express prejudice.

Evidence

Social sharing among ingroup members – gossip, rumor, opinions, stories, media – contribute to consensus in stereotyped beliefs and related prejudices. The most easily communicated traits constitute the core of most stable stereotypes (Schaller & Conway, 2001). The knowledge that their prejudices and stereotypes are shared gives people social permission to express their biases, reinforcing their own and other people’s stereotypes and prejudice. — John F. Dovidio, Peter Glick, Laurie A. Rudman, On the Nature of Prejudice, 331

Categorization

• XREF: Relates to Milgrom’s work on shared community knowledge enabling cooperative behavior — the flip side, where shared consensus enables prejudiced behavior.