In Defense of Natural Law
Natural Law, Liberalsim, and Morality
The Clash of Orthodoxies: Law, Religion, and Morality in Crisis
each of these by Robert P. George.
there are other natural law theorists and theories, but i have found that the theory expounded by these guys (a theory developed by Germain Grisez, Joseph Boyle, and John Finnis) to be the most defensible.
I haven’t read these yet, but they are on my to-read list concerning natural law.
J. Budziszewski is a fairly recent convert and from what I’ve read of his online articles, is very good at explaining complicated concepts in understandable ways.
Above is a link to a class offered by The Teaching Company. The professor offering the class (on cassette - CD - DVD) is a Catholic priest who is a highly regarded philosopher and faculty member of Fordham University, Father Joseph Koterski, S.J.
If you would like a different venue to learn about natural law and its history I would recommend this fine course. It’s more expensive than a book but it’s an enjoyable way to learn in the car going to and from work.
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