The Adaptive Utility of Deontology: Deontological Moral Decision-Making Fosters Perceptions of Trust and Likeability

Although various motives underlie moral decision-making, recent research suggests that deontological moral decision-making may have evolved, in part, to communicate trustworthiness to conspecifics, thereby facilitating cooperative relations. Specifically, social actors whose decisions are guided by deontological (relative to utilitarian) moral reasoning are judged as more trustworthy, are preferred more as social partners, and are trusted more in economic games. The current study extends this research by using an alternative manipulation of moral decision-making as well as the inclusion of target facial identities to explore the potential role of participant and target sex in reactions to moral decisions. Participants viewed a series of male and female targets, half of whom were manipulated to either have responded to five moral dilemmas consistent with an underlying deontological motive or utilitarian motive; participants indicated their liking and trust toward each target. Consistent with previous research, participants liked and trusted targets whose decisions were consistent with deontological motives more than targets whose decisions were more consistent with utilitarian motives; this effect was stronger for perceptions of trust. Additionally, women reported greater dislike for targets whose decisions were consistent with utilitarianism than men. Results suggest that deontological moral reasoning evolved, in part, to facilitate positive relations among conspecifics and aid group living and that women may be particularly sensitive to the implications of the various motives underlying moral decision-making