Xenophobia and Social Closure: A Development of a Model from Coleman

The study builds on the results of an article from James Coleman entitled “Norm-Generating Structures†. In this article Coleman considers whether cooperative behavior establishes itself through evolution as the norm in a social group when group members encounter foreigners occasionally. Since people cooperate in closed social groups the question that Coleman asks is: in what ways is cooperation with foreigners dependent on the degree of social closure? In the article mentioned above Coleman is only able to outline the answer to this question. The goal of this contribution is to broaden Coleman’s model and completely answer the question, whereby it will become clear that Coleman’s results only represent a special case. In general the evolution of cooperation with foreigners is unpredictable, but a low level of xenophobia can be established through evolution under a broad range of circumstances.