To resolve the major controversy about why prosocial behaviors persist in large-scale human societies, we propose that two questions need to be answered. First, how do social interactions in small-scale and large-scale societies differ? By reviewing the exchange and collective-action dilemmas in both small-scale and large-scale societies, we show they are not different. Second, are individual decision-making mechanisms driven by self-interest? We extract from the literature three types of individual decision-making mechanism, which differ in their social influence and sensitivity to self-interest, to conclude that humans interacting with non-relatives are largely driven by self-interest. We then ask: what was the key mechanism that allowed prosocial behaviors to continue as societies grew? We show the key role played by new social interaction mechanisms—change in the rules of exchange and collective-action dilemmas—devised by the interacting individuals, which allow for self-interested individuals to remain prosocial as societies grow.

中文翻译：

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大规模人类社会中的合作——是什么让它独一无二，它是如何进化的？

为了解决关于为什么亲社会行为在大规模人类社会中持续存在的主要争议，我们建议需要回答两个问题。首先，小规模社会和大规模社会中的社会互动有何不同？通过回顾小规模社会和大规模社会中的交换和集体行动困境，我们表明它们并没有什么不同。第二，个人决策机制是否受自身利益驱动？我们从文献中提取了三种类型的个人决策机制，它们的社会影响和对自身利益的敏感性不同，得出的结论是人类与非亲属的互动很大程度上是由自身利益驱动的。然后我们问：随着社会的发展，允许亲社会行为继续存在的关键机制是什么？我们展示了新的社会互动机制所发挥的关键作用——交换规则的变化和集体行动困境——由互动的个人设计，随着社会的发展，这些机制允许自利的个人保持亲社会。