Moral emotion is thought to have evolved to guide our behavior and control our impulse to achieve immediate rewards, thus serving to enforce pro-social behavior. Guilt, one of the moral emotions, is a social, other-oriented emotion that is experienced primarily in interpersonal situations, although it may also be experienced in non-interpersonal situations. We predicted that the intensity of the sense of guilt would differ depending on the relationship between a witness and the person who performed the antisocial behavior because building a good reputation plays an important role in the evolution of reciprocal altruism through indirect reciprocity. Participants were asked to imagine that they had been observed by a third party while committing five kinds of moral transgression based on moral foundation theory, and to describe the intensity of their sense of guilt when witnessed by parents, a cordial friend, a neighbor, or a stranger. The intensity of guilt was significantly lower when the act was witnessed by a stranger regardless of the moral foundation involved. The effects of the kind of witness, however, differed for each moral foundation. The results support the hypothesis that guilt functions to guide our behavior, to achieve cooperation.

人们认为，道德情感的进化是为了指导我们的行为并控制我们获得即时奖励的冲动，从而有助于强化亲社会行为。内疚是道德情感之一，是一种社会性的、以他人为导向的情感，主要在人际情境中经历，尽管也可能在非人际情境中经历。我们预测，内疚感的强度会根据目击者与实施反社会行为的人之间的关系而有所不同，因为建立良好的声誉在通过间接互惠发展互惠利他主义方面发挥着重要作用。根据道德基础理论，参与者被要求想象自己在犯下五种道德违规行为时被第三方观察到，并描述当父母、亲密朋友、邻居或邻居目睹他们的负罪感的强度。一个陌生人。当该行为被陌生人目睹时，无论涉及的道德基础如何，内疚的强度都会明显降低。然而，这种见证的效果因每个道德基础而异。结果支持这样的假设：内疚感可以引导我们的行为，实现合作。