Many important intertemporal decisions are made by groups rather than individuals. What happens to collective decisions when there is internal conflict about the tradeoff between present and future has not been thoroughly investigated so far. We study experimentally the causal effect of group...

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...