People sacrifice personal material gain to favor even minimal in-groups

Evidence

There is further evidence (Turner, 1978a) that the social-competitive pattern of intergroup behavior holds even when it conflicts with obvious self-interest. In this study, the distribution of either monetary rewards or “points” was made, within the minimal intergroup paradigm, between self and an anonymous other, who was either in the ingroup or in the out-group. As long as minimal conditions existed for in-group identification, the subjects were prepared to give relatively less to themselves when the award (either in points or in money) was to be divided between self and an anonymous member of the in-group, as compared with dividing with an anonymous member of the out-group. … These results seem particularly important, since the category of “self,” which is by no means minimal or ad hoc, was set here against a truly minimal in-group category, identical to those used in the earlier experiments. Despite this stark asymmetry, the minimal group affiliation affected the responses. — John T. Jost and Jim Sidanius, Political Psychology, 2726

Categorization

• XREF: Connects to Milgrom’s findings that cooperative equilibria can survive even against self-interest, and to broader evidence on social identity overriding rational self-interest.
• CANDY: A striking, quotable finding: people take less money for themselves to favor a group they were assigned to moments earlier.
• corroborated: 2 independent passages support this claim — John T. Jost and Jim Sidanius, Political Psychology, 2726