Are Naturalism and Moral Realism Compatible?

In a recent paper, Alvin Plantinga has argued that there is good reason to think that naturalism and moral realism are incompatible. He has done so by arguing that the most important argument for the compatibility of these two theses, which has been provided by Frank Jackson, fails and that any other argument that serves the same purpose is likely to fail for the same reason. His argument against the compatibility of naturalism and moral realism, then, is indirect: he argues against it by refuting the most important argument for it. In this article, I argue that Plantinga's argument is unconvincing for at least two reasons. First, Jackson's argument can be revised in such a way that it meets Plantinga's worry. Second, there is another way of arguing for the compatibility of two propositions which Plantinga does not consider. If the naturalist takes this alternative route, she does not face the problem identified by Plantinga. I thus show not only that Plantinga's argument does not count against the compatibility of naturalism and moral realism, but that there is even good reason to think that naturalism and moral realism are in fact compatible. © 2013 Cambridge University Press.