Pt. I. The evolution of cooperation at the level of individuals. Evolutionary foundations of cooperation and group cohesion / Steven A. Frank ; How to evolve cooperation / Christine Taylor and Markin A. Nowak ; Beyond enlightened self-interest : social norms, other-regarding preferences, and cooperative behavior / Samuel Bowles and Herbert Gintis ; Evolution, cooperation, and repeated games / E. Maskin ; Public good games with incentives : the role of reputation / Hannelore De Silva and Karl Sigmund ; Groups and networks : their role in the evolution of cooperation / Brian Skyrms -- Pt. II. Cooperation and group formation. Evolution and construction of moral systems / Jessica C. Flack and David C. Krakauer ; Games, groups, norms, and societies / Simon Levin ; Evolutionary theory and cooperation in everyday life / David Sloan Wilson and Daniel Tumminelli O'Brien ; The error of God : error management theory, religion, and the evolution of cooperation / Dominic D.P. Johnson ; Moral motivation / John E. Hare ; Explaining religion : notes toward a research agenda / Kwame Anthony Appiah -- Pt. III. Cooperation and problems of the commons. Building trust to solve commons dilemmas : taking small steps to test an evolving theory of collective action / Elinor Ostrom ; How democracy resolves conflict in difficult games / Steven J. Brams and D. Marc Kilgour ; Two strategic issues in apologizing / Barry O'Neill ; Neither self-interest nor self-sacrifice : the fraternal morality of market relationships / Robert Sugden