Abstract

This paper has two parts. The first is an exposition of John Foster's argument that ultimate reality, whatever else it might be, is not physical, and could not be. The second part is a somewhat tentative discussion of this argument, in which I consider ways it might be challenged or amended. I suggest that while Foster's argument may not render materialism untenable, at the very least it forces the materialist to adopt certain other controversial views, and so is a force to be reckoned with. I shall use the term physical anti-realism to denote the thesis that ultimate reality does not, and cannot possibly, contain anything material or physical. By physicalism I mean the doctrine that ultimate reality can be physical, at least in part. What Foster means by "ultimate reality" will be explained shortly, but it can be taken roughly to mean: the world as it really is, objectively, as opposed to how it appears to be, or how we conceive it to be. The full-scale version of Foster's argument for physical anti-realism is to be found in the first eleven chapters of The Case for Idealism.2 In the remaining six chapters, he argues that the best way of accommodating this negative result is to adopt a version of phenomenalism, by holding that the physical world exists, but only as a "creation" of contingent constraints on the course of human sensory experience. In what follows, I shall be concerned only with the negative part of Foster's argument, his case against physicalism. Foster himself has recently provided a shorter version of his argument, in "The Succinct Case for Idealism".3 The latter work, henceforth The Succinct Case, as opposed to just The Case, is mainly given over to the anti-realist argument, and provides an excellent introduction to it. The exposition which follows may well be longer than the entire Succinct Case.