Abstract

According to the ancient sorites paradox, zero grains of sand is not enough to make a heap, and adding one single grain can never transform a non-heap into a heap, so there can be no heaps of sand! Similar reasoning applies to all vague terms. In view of this problem, some philosophers have suggested that we must modify classical logic. This chapter argues that there is no need for this, for we should allow that one grain of sand can make the crucial difference, and more generally, that even vague terms have sharp boundaries. This idea is defended by reference to three considerations: the conclusion of Chapter 3, which implies that one should not expect to be able to explain the extension of a predicate in terms of its use; an identification of what sort of meaning-constituting use-practice would engender the distinctive symptoms of vagueness, namely the existence of ‘borderline cases’ to which it is impossible to know whether the predicate applies; and a characterization and invocation of the difference between truth and determinate truth.