On Blackburn’s Response to Mackie’s Moral Error Theory

Abstract J.L. Mackie’s error theory entails that all moral judgments are false. However, Mackie nonetheless maintains that error theorists can continue to engage in moral discourse. In response to Mackie, Simon Blackburn argues that Mackie’s proposal leads error theorists to reinvent a non-cognitivist morality, and that the much more plausible position would be to reject the error theory in favour of non-cognitivism. In this paper, I defend Mackie’s error theory against this objection. I argue that Blackburn makes an unjustified connection between proposed answers to the so-called ‘Now What’ problem and the plausibility of the error theory itself. Moreover, I argue that a revisionary form of non-cognitivism is entirely different from the version of non-cognitivism that philosophers like Blackburn defend, meaning that arguments for revisionary non-cognitivism are not arguments for non-cognitivism in general. This, I argue, undermines a more general objection to the error theory according to which error theorists are guilty of bad faith.