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...

We study the development 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 and indirect reciprocity, and third-party punishment – emerges earliest...

Discrimination is an ubiquitous phenomenon in many societies, but little is known about its origins in childhood. In a framed field experiment, we let 142 three to six-year old preschool children allocate a fixed endowment between an in-group and an out-group receiver in two domains (gender and...