Abstract

This paper argues against Boydian synthetic moral naturalism by way of a critical examination at metasemantic issues. I first show that the Boydian metasemantics delivers determinate but wrong reference, building on an analysis by Schroeter and Schroeter. I then propose a diagnosis which says that the problem occurs due to an overly simple way of understanding externalist metasemantics, and that a proper understanding requires us to pay heed to the higher-level constraints set by the speakers’ deferring pattern. That in turn is restricted by what I call reference defeaters, which are essentially some central beliefs held by the speakers and are so called because they have the power to defeat reference of a term to certain things. Applying the notion to moral discourse, I argue that the entrenched is/ought distinction held by the ordinary speakers defeats the reference of the moral predicates to natural properties, that is, synthetic moral naturalism is not true.