We provide a generalized definition of evolutionary stability of heritable types in arbitrarily large symmetric interactions under random matching that may be assortative. We establish stability results when these types are strategies in games, and when they are preferences or moral values in...

Using James Buchanan's "Samaritan's Dilemma" as a basic example, this paper analyses the problems that have to be solved if strategic behavior is necessary to escape from dilemma situations by changing the opponents' incentives. These problems are addressed within one-shot games as well as...