"Morality, Rationality, and Natural Law"

Public Discourse today published a short essay of mine entitled "Morality, Rationality, and Natural Law."  It is a slightly expanded version of a contribution I made to a Templeton Foundation symposium on the question: "Does Morality Depend on Reasoning?"  The editors of Public Discourse added a headnote that simply says:  "We should prefer natural law thinking to utilitarianism---here's why."  That's not a bad summary of what I seek to show.  Here's my opening paragraph:

If moral norms, including those prohibiting such evils as murder, rape, torture, enslavement, and genocide, are what they purport to be—namely, principles for guiding human choices and actions—then there must be a point to abiding by them; they must have some rational basis. Do they? What could provide such a point and basis?

Here's a link to the essay:  http://www.thepublicdiscourse.com/2010/04/1273