Methodological Naturalism Undercuts Ontological Naturalism

Abstract Naturalism, as I understand it, includes cosmological naturalism, ontological naturalism and methodological naturalism. After clarifying these three theses I argue that the combination of ontological with methodological naturalism is untenable. I do so by providing a pro tanto case against ontological naturalism and show that it can be resisted, but only by abandoning methodological naturalism. The pro tanto case is that ontological naturalism requires a version of what I call Redundancy Nominalism, but methodological naturalists should either reject it or at very least treat it, and hence ontological naturalism, as a speculation.