Citation

Cacault MP, Goette L, Lalive R, Thoenig M. Front. Psychol. 2015; 6: e729.

Affiliation

Department of Economics, University of Lausanne Lausanne, Switzerland.

Copyright

(Copyright © 2015, Frontiers Research Foundation)

DOI

10.3389/fpsyg.2015.00729

PMID

26082737

Abstract

Evolutionary explanations of the co-existence of large-scale cooperation and warfare in human societies rest on the hypothesis of parochial altruism, the view that in-group pro-sociality and out-group anti-sociality have co-evolved. We designed an experiment that allows subjects to freely choose between actions that are purely pro-social, purely anti-social, or a combination of the two. We present behavioral evidence on the existence of strong aggression-a pattern of non-strategic behaviors that are welfare-reducing for all individuals (i.e., victims and perpetrators). We also show how strong aggression serves to dynamically stabilize in-group pro-sociality.

Language: en