Two Problems for an Epistemicist View of Vagueness

Abstract

An epistemicist view about vagueness is any view that includes at least the conjunction of two theses, one thesis that we might call (semantic) optimism, that does not involve the concept of knowledge, and another, properly epistemological thesis. Semantic optimism is the thesis that given any scale of precision relevant to the question whether it applies or not, every predicate has associated with it a sharp cut-off point in that scale between cases in which it applies and cases in which it does not apply. (Thus, there is a number m such that m grains of sand do not make a heap and m + 1 grains do make a heap. There is a number n of hairs such that a man with n hairs or less is bald and a relevantly similar man with n + 1 hairs or more is not bald. And so on.) The second, and properly epistemological thesis of an epistemicist view, is the claim that in borderline cases (and in particular at cut-off points), predicates susceptible of sorites reasoning cannot be known to apply and cannot be known not to apply. In a series of publications, including his recent book (Williamson [1994]) and his paper Imagination, Stipulation and Vagueness (Williamson [1997]), Timothy Williamson has proposed