Abstract

Explaining the supervenience of the moral on the natural is, perhaps, the central metaphysical challenge for the non-naturalist. However, Scanlon (2014) and Fogal and Risberg (2020) have developed a strategy which purports to explain supervenience rather simply. Fogal and Risberg call it the 'Divide and Conquer' strategy. The key idea is to postulate explanatory moral principles linking the natural and the moral. The moral principles are metaphysically necessary, so trivially supervene on the natural. All other moral facts are determined by the necessary moral principles and the natural facts, so they supervene on the natural too. I argue that there are two versions of the Divide and Conquer strategy and both fail. The first strategy doesn’t give an adequate explanation of supervenience because it doesn't properly identify what makes a difference to the holding of supervenience. The second perhaps does give an adequate explanation of supervenience, but only by introducing something similarly puzzling that needs explanation. Consequently, non-naturalists need additional metaphysical machinery to develop their view -- just appealing to moral principles or metaphysical laws won't do the job.