One of the key scientific challenges is the puzzle of human cooperation. Why do people cooperate? Why do people help strangers, even sometimes at a major cost to themselves? Why do people want to punish people who violate norms and undermine collective interests?

This book is inspired by the fact that social dilemmas, defined in terms of conflicts between (often short-term) self-interest and (often longer-term) collective interest, are omnipresent. The book centers on two major themes. The first theme is the theoretical understanding of human cooperation: are people indeed...