Reference Magnets on Normative Twin Earth

Tristram McPherson (Virginia Tech)

Abstract: 'Twin Earth' thought experiments constitute one of the most serious challenges to the semantic program of naturalistic realism in metaethics. This paper develops and defends a response to this challenge that appeals to David Lewis’ theory of reference magnetism: the view that the joints of nature play a distinctive role in determining the reference of our thought and talk. I argue that reference magnets are capable of explaining the Twin Earth intuitions in a way that is compatible with a wide range of other commitments in metaphysics and semantics that a normative realist might adopt.