84 percent of subjects paid to punish, at least once. And even more remarkably, cooperation skyrocketed on the very first round where punishment was allowed, and it kept on climbing. By the twelfth round, the average contribution was fifteen tokens.46 Punishing bad behavior promotes virtue and benefits the group. And just as Glaucon argued in his ring of Gyges example, when the threat of punishment is removed, people behave selfishly.
