People can become less cooperative when threatened with sanctions, and researchers have pointed to both 'intentions' and incentives as sources of this effect. This paper reports data from a novel experimental design aimed at determining the relative importance of intentions and incentives in...

People can become less cooperative when threatened with sanctions, and researchers have pointed to both 'intentions' and incentives as sources of this effect. This paper reports data from a novel experimental design aimed at determining the relative importance of intentions and incentives in...

Evolutionary theory reveals that punishment is effective in promoting cooperation and maintaining social norms. Although it is accepted that emotions are connected to punishment decisions, there remains substantial debate over why humans use costly punishment. Here we show experimentally that...