Joshua Greene is the John and Ruth Hazel Associate Professor of the Social Sciences and director of the Moral Cognition Lab at Harvard University's Department of Psychology. Moral Tribes is his first book although he has made a big splash with his experiments using cutting edge neuroscience and cognitive techniques to find out how people make moral decisions. In this bold and ambitious book, Greene melds philosophy, psychology, and neuroscience to explore our social instincts in this age of raging battles between individuals and groups holding very different values.
At the core of Greene's concern for the daunting challenges facing our society, all the way from global warming down to waste management, is his optimism: "We can improve our prospects for peace and prosperity by improving the way we think about moral problems."
Philosophers have stated that morality is a set of psychological adaptations that allow otherwise selfish individuals to reap the benefits of cooperation. Greene also is firmly convinced that the brain is designed for collaboration even though there is still plenty of conflict around the globe. In terms that are too complicated to replicate here, the author notes that our brains have "automatic settings, emotional responses that allow us to make decisions efficiently, drawing on the precompiled lessons of past genetic, cultural, and individual experience. And our brains have a manual mode, a general capacity for conscious, explicit, practical reasoning that makes human decision making flexible."
Greene says that we've made progress in reducing enmity but there remains room for improvement. He posits that emotions remain the chief cause of the Tragedy of Commonsense Morality, and reason has its place in moving us forward. Greene ends the book with "Six Rules" which will be helpful in creating a global tribe that looks out for everyone.