Nicholas J. J. Smith

This dissertation is concerned with the problem of giving a correct account of the semantics of vague predicates such as '...is tall', '...is bald' and '...is near...'. ;In Chapter 1 I present a definition of vagueness that aims to capture, in a useful form, all our fundamental intuitions about the vagueness of predicates such as those mentioned above; such a definition is lacking in the literature. I also present an abstract characterisation of the Sorites paradox: one that is independent of the particular forms in which the paradox may be presented, and brings to light the essence of the paradox. ;In Chapter 2 I examine existing theories of vagueness. In light of the definition of vagueness defended in Chapter 1, I argue that we need a semantics for vague language that countenances degrees of truth. I distinguish two sorts of degree theory. One sort---which includes the degree form of supervaluation semantics---sees vagueness as an essentially semantic matter. The other sort---which includes accounts based on fuzzy set theory---accounts for vagueness in language in terms of vagueness in the world. I argue that we need a degree theory of the latter, worldly sort. ;In Chapter 3 I examine the fuzzy theory in detail. I show that many of the objections to the fuzzy view that have been raised in the literature do not carry weight. In particular, I defend the coherence of the idea of degrees of truth. However, I isolate a problem for the fuzzy view---the problem of higher-order vagueness---that is serious enough to render the view unacceptable. ;In Chapter 4 I present a new theory of vagueness: one that is intended to share the advantages of the fuzzy view, while avoiding its disadvantages. In particular, this theory accommodates the phenomenon of higher-order vagueness. The theory involves degrees of truth, but they are not the same as the degrees of truth involved in the fuzzy theory. Although the theory involves a non-classical semantics for vague language, this semantics validates classical logic

This paper presents a new argument against A-theories of time. A-theorists hold that there is an objective now (present moment) and an objective flow of time, the latter constituted by the movement of the objective now through time. A-theorists therefore want to draw different pictures of reality—showing the objective now in different positions—depending upon the time at which the picture is drawn. In this paper it is argued that the times at which the different pictures are drawn may be taken to be normal times or hypertimes. If they are normal times then the A-theory is inconsistent, or else collapses to the B-theory—and appealing to primitive tense operators will not help A-theorists avoid this conclusion. If the times are hypertimes then the A-theory is consistent, but deeply problematic none the less

In this paper I present a new argument against vague identity — one that is more fundamental than existing arguments — and I also try to explain why we find the idea of vague identity puzzling, in a way that will dispel the puzzlement. In brief, my argument is this: to make clear sense of something, one must at least model it set-theoretically; but due to the special place of identity in set-theoretic models, any vague relation that one does model set-theoretically will not be identity, for real identity will already be there, built into the background of the model, and perfectly precise.