Perhaps, as Kant thought, making transgressors suffer is a truly worthy goal, just for its own sake. But if that’s right, it’s a remarkable coincidence. How strange if the true principles of justice just happen to coincide with the feelings produced by our punishment gizmos, installed in our brains by natural selection to help us stabilize cooperation and thus make more copies of our genes. Knowing how our brains work and how they got here, it’s more reasonable to suppose that our taste for justice is a useful illusion.

Joshua Greene, Moral Tribes: Emotion, Reason, and the Gap Between Us and Them, New York, 2013, p. 274