Biased assimilation

Biological Parallel

Dominant chimpanzees interpret ambiguous social cues as submission; subordinates interpret the same cues as challenges. Both assimilate new evidence into existing status beliefs. A neutral gesture—reaching for food—is 'deference' when performed by subordinates, 'theft attempt' when performed by equals. The mechanism: prior beliefs about social rank filter all subsequent evidence. Hierarchies become self-reinforcing: each interaction confirms pre-existing status assessments. Evidence doesn't update beliefs; it gets assimilated into them.