Human altruism is a widespread phenomenon that puzzled evolutionary biologists since Darwin. Economic games illustrate human altruism by demonstrating that behavior deviates from economic predictions of profit maximization. A game that most plainly demonstrates this altruistic tendency is the...

In today’s increasingly interconnected world, deciding with whom and at what level to cooperate becomes a matter of increasing importance as societies become more globalized and large-scale cooperation becomes a viable means of addressing global issues. This tension can play out via...