What sort of logic do we get if we adopt a supervaluational semantics for vagueness? As it turns out, the answer depends crucially on how the standard notion of validity as truth preservation is recasted. There are several ways of doing that within a supervaluational framework, the main alternative being between “global” construals (e.g., an argument is valid iff it preserves truth-under-all-precisifications) and “local” construals (an argument is valid iff, under all precisifications, it preserves truth). The former alternative is by (...) far more popular, but I argue in favor of the latter, for (i) it does not suffer from a number of serious objections, and (ii) it makes it possible to restore global validity as a defined notion. (shrink)

This is the first introductory textbook on non-classical propositional logics.

I develop a new argument for an expressivist account of epistemic modals, which starts from a puzzle about epistemic modals which Seth Yalcin recently presented. I reject Yalcin's own solution to the puzzle, and give a better explanation based on expressivism concerning epistemic modals. I also address two alleged problems for expressivism: do embeddings of epistemic modals pose a serious threat to expressivism, and how can expressivism account for disagreements about statements containing epistemic modals?

This article concerns a new constraint on the interaction of quantifier phrases and epistemic modals. It is argued that QPs cannot bind their traces across an epistemic modal, though it is shown that scoping mechanisms of a differentnature are permitted to cross epistemic modals. The nature and source of this constraint are investigated.

Epistemic modal operators give rise to something very like, but also very unlike, Moore's paradox. I set out the puzzling phenomena, explain why a standard relational semantics for these operators cannot handle them, and recommend an alternative semantics. A pragmatics appropriate to the semantics is developed and interactions between the semantics, the pragmatics, and the definition of consequence are investigated. The semantics is then extended to probability operators. Some problems and prospects for probabilistic representations of content and context are explored.