When It’s Good to Feel Bad: An Evolutionary Model of Guilt and Apology

Abstract

We use techniques from evolutionary game theory to analyze the conditions under which guilt can provide individual fitness benefits, and so evolve. In particular, we focus on the benefits of guilty apology. We consider models where actors err in an iterated prisoner's dilemma and have the option to apologize. Guilt either improves the trustworthiness of apology or imposes a cost on actors who apologize. We analyze the stability and likelihood of evolution of such a "guilt-prone" strategy against cooperators, defectors, grim triggers, and individuals who offer fake apologies, but continue to defect. We find that in evolutionary models guilty apology is more likely to evolve in cases where actors interact repeatedly over long periods of time, where the costs of apology are low or moderate, and where guilt is hard to fake. Researchers interested in naturalized ethics, and emotion researchers, can employ these results to assess the plausibility of fuller accounts of the evolution of guilt.

The social function of the feeling and expression of guilt

“…Recent research showed the importance of guilty apology in strong friendship [13]. Moreover, opportunities to make amends are more plentiful among friends than among strangers, which lead to the idea that in order to maintain a strong, honest relationship, punishment might sometimes be necessary [10,11,13]. Our finding supports the idea that guilt has a much stronger function and impact within existing friendships, leading to harsher punishments.…”

“…Alternatively, it could be that participants evaluate the contribution of their partner differently in light of the guilty look. The guilty look might reinforce the information given to the participant that their partner has performed poorly and act as an acknowledgement of the wrongdoer's bad behaviour [ 13 ]. After receiving the feedback from the game, participants did not interact directly anymore.…”

“…People sharing a strong friendship bond have invested a lot of time and resources into the relationship; any disruption to the relationship ought to be repaired in order to save and restore the relationship [ 10 ], regardless of short-term consequences such as punishment. Recent research showed the importance of guilty apology in strong friendship [ 13 ]. Moreover, opportunities to make amends are more plentiful among friends than among strangers, which lead to the idea that in order to maintain a strong, honest relationship, punishment might sometimes be necessary [ 10 , 11 , 13 ].…”

“…The costs could be refusal to cooperate at a later time or damage to the defecting partner's reputation at the scale of the whole social group [12], leading to wider repercussions against the untrustworthy. To regain the good graces of their partners, defectors need to acknowledge their wrongs, make amends and even express remorse regarding their wrongdoing [13]. Moral emotions are, therefore, intimately linked to our relationships with others, [14], facilitating the social interactions and important relationships [15,16].…”

“…Evidence suggests that guilt has a potentially positive function within social interaction by stimulating pro-social behaviours from others, and also promoting actions towards those who have been wronged [ 18 , 20 , 21 ]. As the quality of relationship and likelihood of repeated interaction between two individuals is likely to affect the consequences of social transgressions [ 13 ], however, guilt may perform different roles depending on friendship status. For example, guilt could have a stronger impact within existing friendships compared with new or less close friendships [ 22 , 23 ], as the costs of relationship breakdown are greater.…”