Abstract

Williamson ( 2007 ) argues that philosophers acquire no philosophical knowledge at all by semantic understanding alone. He further argues that the most important method used for achieving philosophical knowledge is through the ‘imaginative simulation’ process some of whose products are neither a priori nor a posteriori but ‘armchair’ knowledge. We argue in this paper that the way Williamson argues against the claim that semantic understanding alone is enough to achieve philosophical knowledge can be paralleled by an exactly similar argument against his view that imaginative simulation alone is enough to achieve philosophical knowledge. Because of the parallel argument, we conclude that Williamson’s argument against semantic understanding shows at most that it is fallible, if used alone, as a method for achieving philosophical knowledge. We also point out a blind spot in Williamson’s argument for his epistemology of modality: a reliable method for achieving knowledge about subjunctive conditionals is not necessarily a reliable method for achieving knowledge about modal statements even if every modal statement is logically equivalent to some subjunctive conditional. Finally, we argue that, with a suitable understanding of ‘understanding the meaning,’ Williamson’s armchair knowledge is nothing but the a priori knowledge of those good-old-days philosophy.