Stephen Schiffer

Although there is a vast literature on whether propositional attitudes are relations to propositions, a crucial question that ought to lie at the heart of this debate is not often enough seriously addressed. This is the question of the contribution propositions make to the ways in which we benefit from having our propositional-attitude concepts, if those concepts are concepts of relations to propositions. Unless propositions can be shown to confer a benefit that no non-propositions could provide, we should probably doubt whether propositional attitudes really are relations to propositions. I believe that propositional attitudes are relations to propositions and that the role played by them in our conceptual economy cannot be played by things of any other kind, and in this paper I try to say why. This paper, in other words, offers my answer to the question posed by my title.

A single argument template---the EPH template---can be used to generate versions of the best known and most challenging skeptical problems. In his brilliantly groundbreaking book Knowledge and Its Limits, Timothy Williamson presents a theory of knowledge and evidence which he clearly intends to provide a response to skepticism in its most important forms. After laying out EPH skepticism and reviewing possible ways of responding to it, I show how elements of Williamson’s theory motivate a hitherto unexplored way of responding to EPH-generated skeptical arguments. Then I offer reasons to doubt the correctness of Williamson’s response