Merely categorizing people into groups triggers biased evaluation, even on trivial features

Evidence

A critical question to be addressed in any consideration of intergroup relations is, “How do in-groups and, by extension, out-groups, come about?” Tajfel (1970, 1978, 1981) provided one answer to this question— an admittedly incomplete one—when he discovered that people often display a propensity to group themselves and those around them into meaningful social categories on the basis of even trivial features, and to use these groupings in evaluating others who are, or are not, included in the grouping. This mere categorization tendency has been more than adequately documented in research using the minimal group paradigm and has been the source of hundreds of social psychological studies, many of which look suspiciously like others that already have seen the light of day. — Roderick M. Kramer, Geoffrey J. Leonardelli, Robert W. Livingston, Social Cognition, Social Identity, and…, 1375

Categorization

• XREF: Connects to the reader’s prejudice-psychology thread — Tajfel’s mere categorization is a core mechanism-level causal account of ingroup/outgroup formation that grounds Islamophobia/antisemitism research. — connects to: Merely categorizing people into us and them produces discrimination against them — Leonard S. Newman and Ralph Erber (eds.), Understanding Genocide: The Social…, 88
• QUESTION: The author flags Tajfel’s answer as ‘admittedly incomplete’ — worth chasing what critiques exist of minimal-group findings for real-world intergroup hostility.
• corroborated: 2 independent passages support this claim — Roderick M. Kramer, Geoffrey J. Leonardelli, Robert W. Livingston, Social Cognition, Social Identity, and…, 1375