|Institut für Empirische Wirtschaftsforschung, Zürich, Switzerland|
Humans are outliers in the animal world in that they frequently cooperate in large groups of genetically unrelated strangers. Experimental evidence and evolutionary models suggest that altruistic punishment, the propensity to punish unfair and uncooperative behavior, is an important element for human cooperation. In the talk, I will present experimental evidence on the patterns of altruistic punishment. This evidence will be the basis for a discussion of different proximate models of humans' propensity for altruistic punishment as inequity aversion or intention based reciprocity. Although the models differ in detail, they have in common that they assume that people have some utility from punishing. In line with this idea, it has been shown that the punishment of defectors activates reward related neural circuits in the brain.