Publication Date




Embargo Period


Degree Name

Master of Science (MS)


Psychology (Arts and Sciences)

Date of Defense


First Committee Member

Michael E. McCullough

Second Committee Member

Debra Lieberman

Third Committee Member

J. Albert C. Uy


Some researchers have recently promoted the idea that humans possess an instinct to “altruistically” punish social norm violators—that is, to intervene as unaffected third parties and punish transgressors at a personal cost, even when they have no hope of reaping any direct benefit from the punishment. Both the evolutionary theorizing and the empirical findings that are marshaled in support of this claim have been called into question, and results from a recent investigation strongly suggest that humans do not, in fact, punish altruistically as third parties on behalf of strangers. However, humans do engage in third-party punishment on behalf of people with whom they have a vested fitness interest, such as friends and kin. Herein it is proposed that empathy and anger are the proximate mechanisms that produce third-party punishment, and that they are only experienced when a third-party has a sufficiently high vested fitness interest in the victim of a transgression. Thus, the lack of third-party punishment on behalf of strangers can be explained proximately by the absence of empathy toward the victim and anger toward the transgressor. In a laboratory experiment with 212 participants, it was found that experimentally manipulated empathy felt toward a stranger increased anger at unfairness, and quasi-experimental comparisons with a previous experiment suggest that these differences in empathy and anger can produce third-party punishment. These findings provide preliminary support for the proposed model of third-party punishment and shed light on directions for future research on this topic.


third-party punishment; anger; empathy; evolutionary psychology; altruism