Abstract
The extent to which God grounds normativity within natural law theory is analyzed. I examine Hugo Grotius’s understanding of natural law and human nature and show that Grotius makes few explicit metaphysical commitments which makes his view open to development in at least two different ways. Then a Thomistic view of natural law and human nature is developed. It is shown that Grotius’s position could be developed as a proto-new natural law theory, but this leaves it open to powerful objections from Fulvio Di Blasi and other Thomistic philosophers. Finally, I argue that a view can be developed in such a way as to take on certain elements of the Thomistic view, particularly its metaphysics, but still maintain the famous Grotian claim that human nature can establish normativity without God. The key to this is the distinction between the order of knowing and the order of being.