For example: we can compare how ethical traditions do in Prisoner’s Dilemmas against the game’s best strategy, called Tit-For-Tat, which is an “evolutionarily stable strategy.” As Tomas Sedlacek asks: What would Christians do? Or practitioners of any religious or secularly sourced Golden Rule? The results are clear: Rationalists do worse than the Golden Ruled. And Jewish preferences beat Christian ethics. So-called rationalists, dominated by some dire logic, produce no cooperation and low productivity. Two Golden Ruled players cooperate, thus beating rationalists. But New Testament turning-the-other-cheek is exploitable (as Machiavelli and Nietzsche complained). Old Testament eye-for-an-eye comes closer to Tit-For-Tat, if forgiveness follows (which might be divine, but is also evolutionarily adaptive). - blogs.scientificamerican.com