 Human Reciprocity and Its Evolution" (2011) and "Schooling in Capitalist America", first published in 1976.Bowles has recently studied the way that people are motivated by selfishness and the desire to maximize their own income as compared to altruism and the desire to do a good job and be well regarded by others.Real-world experiments show that contrary to traditional economic theories market incentives destroy cooperation and are less efficient than voluntary, altruistic behavior "in most cases."