Ontological Naturalism holds that our fundamental ontology contains only those generally natural objects, properties, and relations required by our best scientific theory. Logical principles are thought of as being normative of correct inference and as involving necessary truths and relations. Necessary relations are stronger than the relations described by science; norms are traditionally thought to be separate from the descriptive project of science. Yet, ontological theories, including ontological naturalism, employ logic freely without offering an account of logical normativity and necessity. (...) It appears that logical properties and relations are prima facie non-natural. If so, then ontological naturalism paradoxically presupposes the presence of non-natural properties and relations as a part of the ultimate fundamental ontology. I explore this tension between logic and ontology as a means to clarifying the standards of acceptability for ontological theories generally and as a means to clarifying the character of logical discourse. I conclude that all proposed ontological theories must provide a substantive account of logic which respects its intrinsic modal and normative character as a minimal test of meta-ontological acceptability. (shrink)