The evolution of large-scale cooperation among genetic strangers is a fundamental unanswered question in the social sciences. Behavioral economics has persuasively shown that so called strong reciprocity plays a key role in accounting for the endogenous enforcement of cooperation. Insofar as...

The evolution of large-scale cooperation among genetic strangers is a fundamental unanswered question in the social sciences. Behavioral economics has persuasively shown that so called ‘strong reciprocity’ plays a key role in accounting for the endogenous enforcement of cooperation. Insofar...