In this paper I develop an argument against a type of Non-Analytic Normative Naturalism. This argument, the Normative Property Dualism Argument, suggests that, if Non-Analytic Normative Naturalists posit that normative properties are identical to natural properties and that such identities are a posteriori, they will be forced to posit that these properties which are both normative and natural have higher-order normative properties of their own.