Abstract

In his 2013 book, “Moral Tribes: Emotion, Reason, and the Gap between Us and Them,” Joshua Greene1 contemplates two tragedies. The first is the tragedy of the commons, a well- studied problem in the game theory and psychology literature. Here, if people are truly self- interested, cooperation cannot arise, and everyone will use the commons until it is depleted. This problem is succinctly called the “Me vs. Us” problem. The second is the tragedy of the commonsense morality, which Greene named, refers to the problem of cooperation among groups, the “Us vs. Them” problem.