Jun Kobayashi

     This note extends the concept of evolutionarily stable strategy from symmetric two-player random matching games to games with more than two players. First, I extend the definition of evolutionarily stable strategy. Second, I show, as the necessary and sufficient condition of the definition, the procedure to check whether a strategy is evolutionarily stable or not.

     This article argues that, during repeated unanimous consensus makings, evaluating strategies that assign a whole weight to a specific individual are evolutionarily stable. Evaluating strategies represent ways of evaluating alternatives with respect to others' utilities. I derive the following three conclusions: first, when a consensus is reached by two individuals, the maximin strategy evolves rather than the utilitarian strategy or the selfish strategy. Second, this result is robust for consensuses comprising two or more individuals. Finally, in general, concerns for a specific individual evolve.