Understanding the roots of human cooperation among strangers is of great importance for solving pressing social … dilemmas and maintening public goods in human societies. We study the development of cooperation in 929 young children, aged 3 … to 6. In a unified experimental framework, we examine which of three fundamental pillars of human cooperation − direct …

We study the developmental roots of cooperation in 929 young children, aged 3 to 6. In a unified experimental framework …, we examine pre-registered hypotheses about which of three fundamental pillars of human cooperation - direct reciprocity …, indirect reciprocity, and third-party punishment - emerges earliest and is more effective as a means to increase cooperation in …