Moral Metaphysics for Expressivists: Why We Should Be Error Theorists, Not Deflationists

Abstract

Many metaethicists do moral metaphysics. That is, they engage in moral thought, discourse and inquiry that makes overt reference to metaphysical-sounding concepts like ‘facts’ and ‘properties.’ Expressivism in metaethics is a position which holds that moral discourse semantically expresses desire-like attitudes. How can expressivists give a meta-philosophical account of what we are doing when we do moral metaphysics? In this paper, I argue that quasi-realist expressivists’ standard strategy of appealing to deflationism to account for moral metaphysics is unsatisfactory. I propose a partial error theory of moral metaphysics that does better. This error theory is part of my proposed modified version of expressivism, which I call ‘disjunctive expressivism’. The central argumentative strategy of the paper is as follows. I argue that the quasi-realist deflationist approach to moral metaphysics lacks explanatory and semantic power, as it cannot make sense of first-order moral disagreement on an issue I call Insistence on Authority. This first-order disagreement arises between cognitivist objectivist realists, who tend to hold that external metaphysical legitimation is required to justify morally sanctioning and judging others, and expressivists and subjectivists, who tend to deny that such legitimation is required. Furthermore, quasi-realists themselves seem to be keen on criticizing cognitivist objectivist realists on this front, but they lack the semantic resources to do so. Disjunctive expressivism, with its associated partial error theory, offers an attractive solution to these problems.