This book explains the foundation of what we all know to be right and wrong and shows how that foundation has been kicked out from under western society. Budziszewski questions the modern assumption that moral truths are unknowable. With logical arguments he rehabilitates the natural law tradition and restores confidence in a moral code based upon human nature. He offers a foothold to those who attempt either to understand or defend the reasonableness of traditional morality. He believes that natural law theory has entered a new phase, in which theology will again have pride of place. While religious belief might seem to hamper the search for common ground, he shows that it is not an obstacle, but a pathway to apprehending universal norms of behavior.