Department of Human Behavior, Ecology, and Culture, Max Planck Institute for Evolutionary Anthropology, DE, Leipzig, Germany.
LEVYNA: Laboratory for the Experimental Research of Religion, Masaryk University, CZ, Brno, Czech Republic; Department of Human Evolutionary Biology, Harvard University, Cambridge, United States.
Cognition. 2019 May;186:1-6. doi: 10.1016/j.cognition.2019.01.015. Epub 2019 Feb 1.
Identity fusion theory has become a popular psychological explanation of costly self-sacrifice. It posits that while maintaining one's own individual identity, a deep affinity with one's group can contribute to sacrifice for that group. We test this and related hypotheses using a behavioral economic experiment designed to detect biased, self-interested favoritism among eight different populations ranging from foragers and horticulturalists to the fully market-integrated. We find that while individuals favor themselves on average, those with higher ingroup fusion sacrifice more money to other members of their ingroup who are unable to reciprocate. We also find that positive outgroup relations has a similar effect. Additionally, we assess a recently-posited interaction between ingroup and outgroup relations and show no consistent effect at the individual or sub-sample levels.
身份融合理论已成为一种解释高代价自我牺牲的流行心理学理论。它假设，在保持自身个体身份的同时，与自身群体的深厚亲和力可以促使为该群体做出牺牲。我们使用一种行为经济学实验来检验这一假说和相关假设，该实验旨在检测从觅食者和园艺家到完全融入市场的 8 个不同群体中存在的有偏差的、自私的偏袒行为。我们发现，尽管个体平均偏向于自己，但那些融合程度较高的人会为无法回报的同组成员牺牲更多的钱。我们还发现，积极的外群体关系也有类似的效果。此外，我们评估了最近提出的内群体和外群体关系之间的相互作用，但在个体或子样本层面上没有发现一致的影响。
