Ethical Non-naturalism and the Guise of the Good

The paper presents a positive argument for a version of metaphysically light ethical non-naturalism from the nature of mental states such as desires. It uses as its premise the time-honoured, and recently rediscovered, doctrine of the guise of the good, whereby it is essential to desire (and perhaps similar mental states) that the object of desire be conceived as good or as normatively favoured under some description. The argument is that if the guise of the good is a correct theory of desire, then a certain version of non-naturalism is better placed than other meta-ethical views to make sense of it. First I define ethical non-naturalism and the guise of the good, providing also an initial defence of the latter. Then I briefly survey some historical precedents and proceed to the argument. For each major meta-ethical view I consider (reductive and non-reductive naturalism, error theory, non-cognitivism, and finally robust non-naturalism) I offer reasons why combining them with the guise of the good leads to consequences that are or should be unwelcome by the guise of the good. At the end of this elimination process a form of relatively metaphysically light non-naturalism will emerge as the view that best fits with the guise of the good.