Both a primer on natural law, and a vigorous academic defense of it, Written on the Heart is an informative and insightful look into the moral and ethical foundations of human culture. From the Christian standpoint, there are obvious limitations on natural law, including the fact that "it tells us what sin is, [but] it tells us nothing of how to escape it." Budziszewski does a masterful job of noting the limitations and capabilities of natural law, as he examines several of the major players involved in its formation and history.
He has chosen to look at Aristotle (considered the forebear of much natural law thought and thinking), Thomas Aquinas (the best Christian expositor of natural law), John Locke (the influential writer who was a guiding force behind the American experiement in democracy and government), and John Stuart Mill (one of the best modern opponents of natural law). His introductions to the thoughts of these four men gives us a broad look at the history and development of natural law.
After looking at the history and development of natural law, Budziszewski then offers a Christian appraisal of natural law, and a look at the contemporary natural law arena, focusing on Catholic, Protestant, Jewish, and secular views of natural law. He focuses on the political implications of natural law, arguing that the existence of the natural law is known and that its content is knowable to all people. Natural law has been repressed, however, and Budziszewski eloquently argues that natural law concepts deserve much greater respect than they have often been given.
This is a great introduction to a vast and important topic. The author offers a profound analysis of great natural law thinkers and opponents, and offers suggestions for further reading. He is well-versed, and his defense of natural law deserves academic respect. This is a truly valuable book on a truly valuable topic.