Can the Canberrans’ Supervenience Argument Refute Shapeless Moral Particularism?

Frank Jackson, Michael Smith, and Philip Pettit contend in their 2000 paper that an argument from supervenience deals a fatal blow to shapeless moral particularism, the view that the moral is shapeless with respect to the natural. A decade has passed since the Canberrans advanced their highly influential supervenience argument. Yet, there has not been any compelling counter-argument against it, as far as I can see. My aim in this paper is to fill in this void and defend SMP against the Canberrans’ supervenience argument. Such being the case, I will firstly re-construct the Canberrans’ supervenience argument in detail and push it as far as it can go. In fact, I will defend it against a number of existing objections respectively from Garfield, Dancy, and McDowell. Next, I will argue, however, that the supervenience argument, despite its initial plausibility, has one major pitfall: it hinges on an overly permissive conception of ‘shape’ such that it does not generate the right kind of moral principles the shapeless moral particularists are concerned to refute. I thus conclude that the seemingly scathing supervenience argument turns out to be toothless against SMP. Although this would not prove SMP to be right, for it might attract criticisms from other fronts, yet, until they come up, SMP, contrary to prevalent conceptions, remains alive and kicking.