Studies of cooperation in infinitely repeated matching games focus on homogeneous economies, where full cooperation is …

Under what conditions can cooperation be sustained in a network of strangers? Here we study the role of institutions … possible, including full intertemporal cooperation supported by a social norm based on community punishment of defectors. We … coordination on intertemporal cooperation in ways that networks of strangers were unable to achieve through social norms. …

achieve cooperation. Empirically, without a working monetary system, participants were reluctant to expand the scale of … interaction; and when they did, they ended up destroying surplus compared to partnerships, because cooperation collapsed in large …