Vagueness provides the first comprehensive examination of a topic of increasing importance in metaphysics and the philosophy of logic and language. Timothy Williamson traces the history of this philosophical problem from discussions of the heap paradox in classical Greece to modern formal approaches such as fuzzy logic. He illustrates the problems with views which have taken the position that standard logic and formal semantics do not apply to vague language, and defends the controversial realistic view that vagueness is a kind (...) of ignorance--that there really is a grain of sand whose removal turns a heap into a non-heap, but we cannot know which one it is. (shrink)

The central thesis of the book is that the proposition a vague sentence expresses in a borderline case is true or false, and we cannot know which. We are ignorant of its truth-value. This is the epistemic view of vagueness. It allows us to preserve both classical logic and disquotational principles about truth and falsity, with all their advantages: simplicity, clarity, power, past success, integration with well-confirmed theories in other domains. Consequently, the epistemic view has a head start over its (...) rivals. The gap is widened by each rival theory's specific disadvantages, many of them related to higher-order vagueness. The epistemic view is then strengthened by an explanation of our ignorance in borderline cases. The explanation predicts higher order vagueness. (shrink)

The central thesis of the book is that the proposition a vague sentence expresses in a borderline case is true or false, and we cannot know which. We are ignorant of its truth-value. This is the epistemic view of vagueness. It allows us to preserve both classical logic and disquotational principles about truth and falsity, with all their advantages: simplicity, clarity, power, past success, integration with well-confirmed theories in other domains. Consequently, the epistemic view has a head start over its (...) rivals. The gap is widened by each rival theory's specific disadvantages, many of them related to higher-order vagueness. The epistemic view is then strengthened by an explanation of our ignorance in borderline cases. The explanation predicts higher order vagueness. (shrink)

A standard response to the problem of diachronic vagueness is ‘the semantic solution’, which demands an abundant ontology. Although it is known that the abundant ontology does not logically preclude endurantism, their combination is rejected because it necessitates massive coincidence between countless objects. In this paper, I establish that the semantic solution is available not only to perdurantists but also to endurantists by showing that there is no problem with such ubiquitous and principled coincidence.

Roy Sorenson offers a unique exploration of an ancient problem: vagueness. Did Buddha become a fat man in one second? Is there a tallest short giraffe? According to Sorenson's epistemicist approach, the answers are yes! Although vagueness abounds in the way the world is divided, Sorenson argues that the divisions are sharp; yet we often do not know where they are. Written in Sorenson'e usual inventive and amusing style, this book offers original insight on language and logic, the way world (...) is, and our understanding of it. (shrink)

Precis of my book by this title, for a symposium.

If you’ve read the first five hundred pages of this book, you’ve read most of it (we assume that ‘most’ requires more than ‘more than half’). The set of natural numbers n such that the first n pages are most of this book is nonempty. Therefore, by the least number principle, it has a least member k. What is k? We do not know. We have no idea how to find out. The obstacle is something about the term ‘most’. It (...) is recognisably the same feature as the feature of ‘heap’ that prevents us from finding an answer to the question ‘How many grains make a heap?’ and the feature of many other expressions that prevents us from finding answers to similar questions involving them. Call this feature, whatever its underlying nature, vagueness. (shrink)

Four- Dimensionalism defends the thesis that the material world is composed of temporal as well as spatial parts. This defense includes a novel account of persistence over time, new arguments in favour of the four-dimensional ontology, and responses to the challenges four- dimensionalism faces." "Theodore Sider pays particular attention to the philosophy of time, including a strong series of arguments against presentism, the thesis that only the present is real. Arguments offered in favour of four- dimensionalism include novel arguments based (...) on time travel, the debate between spacetime substantivalists and relationalists, and vagueness. Also included is a comprehensive discussion of the paradoxes of coinciding material objects, and a novel resolution of those paradoxes based on temporal counterpart theory. In conclusion Sider replies to prominent objections to four- dimensionalism, including discussion of the problem of the rotating homogenous disk. (shrink)