Third-party punishment of antisocial others is unique to humans and seems to be universal across cultures. However, its emergence in ontogeny remains unknown. We developed a participatory cognitive paradigm using gaze-contingency techniques, in which infants can use their gaze to affect agents displayed on a monitor. In this paradigm, fixation on an agent triggers the event of a stone crushing the agent. Throughout five experiments (total N = 120), we show that eight-month-old infants punished antisocial others. Specifically, infants increased their selective looks at the aggressor after watching aggressive interactions. Additionally, three control experiments excluded alternative interpretations of their selective gaze, suggesting that punishment-related decision-making influenced looking behaviour. These findings indicate that a disposition for third-party punishment of antisocial others emerges in early infancy and emphasize the importance of third-party punishment for human cooperation. This behavioural tendency may be a human trait acquired over the course of evolution.

对反社会他人的第三方惩罚是人类独有的，而且似乎在不同文化中都是普遍存在的。然而，它在个体发育中的出现仍然未知。我们使用凝视应急技术开发了一种参与式认知范式，其中婴儿可以使用他们的凝视来影响监视器上显示的代理。在这个范例中，对代理的固定会触发石头压碎代理的事件。通过五个实验（总共N = 120），我们发现八个月大的婴儿会惩罚反社会的其他人。具体来说，婴儿在观看攻击性互动后，会增加对攻击者的选择性观察。此外，三项对照实验排除了对其选择性注视的其他解释，这表明与惩罚相关的决策会影响注视行为。这些发现表明，对反社会他人进行第三方惩罚的倾向在婴儿早期就出现了，并强调了第三方惩罚对人类合作的重要性。这种行为倾向可能是人类在进化过程中获得的特征。