发表机构
Toulouse School of Economics; Monash University（图卢兹经济学院; 莫纳什大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过评估所有1,048,576个道德系统，发现稳定合作需“区分性”策略与“一致性”规范配对，其中“悔悟的区分者”在各类社会困境中普遍稳定，揭示道德一致性是间接互惠合作的核心。
AI 中文摘要
关于人类为何与陌生人合作的一个主要解释是间接互惠：当行为被观察时，个体通过帮助值得帮助的人来获得良好声誉。先前的研究已经识别出许多通过间接互惠维持合作的“道德系统”——每个系统将一种行动策略与一种评判他人的规范配对——然而，是什么使这些系统成功，以及这种成功是否能推广到捐赠博弈之外，仍不清楚。在此，我们评估了所有1,048,576个道德系统，其规范以双方玩家的声誉和行动为条件，涵盖每一个两人社会困境。我们发现，每一个高度稳定、合作的系统都将一种“区分性”策略——即在良好声誉下帮助好人、拒绝坏人——与一种“一致性”规范配对，该规范认为那些按策略要求行动的人为善。这样的系统“言行一致”且“言传身教”。在小误差的极限下，只有一种策略与一致性规范配对在所有社会困境中保持稳定：“悔悟的区分者”，当其声誉不佳时通过合作来弥补。我们的结果统一了数十年来关于间接互惠的研究，揭示道德一致性是每一个稳定、合作的道德系统的共同要素。
英文摘要
A leading explanation for why humans cooperate with strangers is indirect reciprocity: when conduct is observed, individuals earn good reputations by cooperating with the deserving. Previous research has identified many "moral systems" that sustain cooperation through indirect reciprocity - each pairing a strategy for how to act with a norm for how to judge others - yet what makes them succeed, and whether that success generalizes beyond the donation game, has remained unclear. Here we evaluate all 1,048,576 moral systems whose norms condition on both players' reputations and actions, across every two-player social dilemma. We find that every highly stable, cooperative system pairs a "discriminating" strategy - one that cooperates with the good and defects against the bad when in good standing - with a "consistent" norm that deems good exactly those who act as the strategy prescribes. Such systems "practice what they preach" and preach what they practice. In the limit of small errors, only one strategy paired with a consistent norm remains stable across all social dilemmas: the "contrite discriminator", which cooperates to make amends when its standing is bad. Our results unify decades of research on indirect reciprocity, revealing moral consistency as the common ingredient of every stable, cooperative moral system.
CommentsMain text (27 pages, 4 figures, 4 Extended Data figures) and Supplementary Information (90 pages) in one PDF. Code: https://doi.org/10.5281/zenodo.21519395
