Desire-based Reasons, Naturalism, and the Possibility of Vindication : Lessons from Moore and Parfit

Abstract

The aim of the paper is to critically assess the idea that reasons for action are provided by desires (the Model). I start from the claim that the most often employed meta-ethical background for the Model is ethical naturalism; I then argue against the Model through its naturalist background. For the latter purpose I make use of two objections that are both intended to refute naturalism per se. One is G. E. Moore’s Open Question Argument (OQA), the other is Derek Parfit’s Triviality Objection (TO). I show that naturalists might be able to avoid both objections in case they can vindicate the reduction proposed. This, however, leads to further conditions whose fulfilment is necessary for the success of vindication. I deal with one such condition, which I borrow from Peter Railton and Mark Schroeder: the demand that naturalist reductions must be tolerably revisionist. In the remainder of the paper I argue that the most influential versions of the Model are intolerably revisionist. The first problem concerns the picture of reasons many recent formulations of the Model advocate. By using an objection from Michael Bedke I show that on this interpretation obvious reasons won’t be accounted for by the Model. The second problem concerns idealization that is also often part of the Model. Invoking an argument by Connie Rosati, I show that the best form of idealization, the ideal advisor account, is inadequate. Hence, though not knock down arguments as they were intended to be, OQA and TO do pose a serious threat to the Model.