Abstract

This essay criticizes Williamson’s attempt, in his book, The Philosophy of Philosophy, to undermine the interest of the a priori–a posteriori distinction. Williamson’s argument turns on several large claims. The first is that experience often plays a role intermediate between evidential and merely enabling, and that this poses a difficulty for giving a theoretically satisfying account of the distinction. The second is that there are no constitutive understanding–assent links. Both of these claims are subjected to detailed scrutiny. In particular, it is argued that Williamson’s case of the deviant logician, Simon, fails to constitute an intelligible counterexample to the status of conjunction elimination as an understanding–assent link for ‘and’.