Human groups maintain a high level of sociality despite a low level of relatedness among group members. The behavioral basis of this sociality remains in doubt. This paper reviews the evidence for an empirically identifiable form of prosocial behavior in humans, which we call "strong...

We study the impact of advice or observation on the depth of reasoning in an experimental beauty-contest game. Both sources of information trigger faster convergence to the equilibrium. Yet, we find that subjects who receive naïve advice outperform uninformed subjects permanently, whereas...

This paper experimentally explores how the enforcement of cooperative behavior in a social dilemma is facilitated through institutional as well as emotional mechanisms. Recent studies emphasize the importance of negatively valued emotions, such as anger, which motivate individuals to punish free...