Bowles, Samuel; Gintis, Herbert - Santa Fe Institute - 1998
-oriented preferences. We call this strong reciprocity. We distinguish this from weak reciprocity, namely reciprocal altruism, tit … reciprocity in human society. However, where benefits and costs are measured in fitness terms and where the relevant behaviors are … reciprocity cannot invade a population of non-reciprocators, nor can it be sustained in a stable population equilibrium. We show …