Most previous studies regarding self-punishment have focused on the correlation between moral emotion and self-punishment. Only a few studies have attempted to understand self-punishment from the perspective of seeking forgiveness, and no study has yet directly tested whether wrongdoers' self-punishment promotes others to forgive the wrongdoers. In three studies, the participants judged the wrongdoers' self-punishment behaviors following an unfair allocation and reported the extent to which they forgave the wrongdoers. The results demonstrated that self-punishment did promote forgiveness in both the direct (Studies 1 and 2) and indirect reciprocity (Study 3) contexts. Consistent with costly signaling theory, the costlier the self-punishment was, the stronger the effect it had on forgiveness. Moreover, communicative self-punishment had a better effect than silent self-punishment when the cost was relatively high in the direct-reciprocity studies. These findings can guide us regarding how to address a damaged relationship via self-punishment when compensation is not feasible or acceptable.
Keywords: Self-punishment; communicative; cost; forgiveness; silent.