Publication Date




Embargo Period


Degree Type


Degree Name

Master of Science (MS)


Psychology (Arts and Sciences)

Date of Defense


First Committee Member

Michael E. McCullough

Second Committee Member

Elizabeth R. Losin

Third Committee Member

William A. Searcy


Theorists of human nature have long debated whether prosocial behavior is always self-interested, or instead is at least sometimes explained by altruism or moral motivation. Experiments testing the empathy-altruism hypothesis appear to confirm the existence of altruism, while results from an experimental economic paradigm called the “dictator game” provide evidence of moral motivation. However, both experimental paradigms feature an explicit prompt to behave prosocially. Explicit prompts make the helping opportunity common knowledge among the participant, experimenter, and (sometimes) the potential recipient, and therefore confound unselfishness with a self-interested desire to avoid social censure. The present experiment (N= 334) recreated both the empathy-altruism and dictator game paradigms and manipulated whether the opportunity to benefit another person was explicitly prompted or merely permissible. Removing the explicit prompt dramatically reduced prosocial behavior: Giving in the dictator game paradigm disappeared completely, while giving in the empathy-altruism paradigm was attenuated and not explained by empathy. Empathy only predicted prosocial behavior when the ability to engage in prosocial behavior was common knowledge. These results undercut previous evidence that altruistic and moral considerations motivate prosocial behavior and suggest that empathy tracks the magnitude of perceived social censure from failing to help needy persons.


empathy-altruism hypothesis; dictator game; common knowledge; prosocial behavior