Economists have a long tradition in identifying the evolution of cooperation in large, unstructured societies as a puzzle. We suggest a new explanation for cooperation which avoids restrictions of most previous attempts. Our explanation deals with the role of internalized norms for cooperation...

That institutions matter is widely accepted among economists and so are social norms as an important category of informal institutions. Social norms matter in many economic situations, but in particular for markets. The economic literature has studied the interrelation between markets and social...