Cian Dorr

Timothy Williamson has shown that the B axiom for 'definitely' (α → Δ¬Δ¬α) guarantees that if a sentence is second-order vague in a Kripke model, it is nth order vague for every n. More recently, Anna Mahtani has argued that Williamson's epistemicist theory of vagueness does not support the B axiom, and conjectured that if we consider models in which the “radius of accessibility” varies between different points, we will be able to find sentences that are nth-order vague but (n+1)th-order precise, for any n. This paper bolsters Mahtani's argument, shows her conjecture to be true, and shows that imposing certain further natural constraints on "variable radius" models does not change the situation.

This paper considers how counterfactuals should be evaluated on the assumption that determinism is true. I argue against Lewis's influential view that the actual laws of nature would have been false if something had happened that never actually happened, and in favour of the competing view that history would have been different all the way back. I argue that we can do adequate justice to our ordinary practice of relying on a wide range of historical truths in evaluating counterfactuals by saying that, in typical cases, history would have been only *very slightly* different until shortly before the relevant time. The paper also draws some connections between the puzzle about counterfactuals under determinism and the debate about whether determinism entails that no-one can ever do otherwise than they in fact do.

Seth Yalcin has pointed out some puzzling facts about the behaviour of epistemic modals in certain embedded contexts. For example, conditionals that begin ‘If it is raining and it might not be raining, … ’ sound unacceptable, unlike conditionals that begin ‘If it is raining and I don’t know it, … ’. These facts pose a prima facie problem for an orthodox treatment of epistemic modals as expressing propositions about the knowledge of some contextually specified individual or group. This paper develops an explanation of the puzzling facts about embedding within an orthodox framework.

Most meanings we express belong to large families of variant meanings, among which it would be implausible to suppose that some are much more apt for being expressed than others. This abundance of candidate meanings creates pressure to think that the proposition attributing any particular meaning to an expression is modally plastic: its truth depends very sensitively on the exact microphysical state of the world. However, such plasticity seems to threaten ordinary counterfactuals whose consequents contain speech reports, since it is hard to see how we could reasonably be confident in a counterfactual whose consequent can be true only if a certain very finely tuned microphysical configuration obtains. This essay develops the foregoing puzzle and explores several possible solutions.

I motivate and briefly sketch a linguistic theory of vagueness, on which the notion of indeterminacy is understood in terms of the conventions of language: a sentence is indeterminate iff the conventions of language either forbid asserting it and forbid asserting its negation, under the circumstances, or permit asserting either. I then consider an objection that purports to show that if this theory (or, as far as I can see, any other theory of vagueness that deserved the label "linguistic" were true, there would be no such thing as indeterminacy. I respond to this objection by arguing on independent grounds against its main premise, the widely-accepted claim that if it is indeterminate whether P, no human being knows whether P. I defend an alternative view according to which, when it is indeterminate whether P, it is often also indeterminate whether we know that P.

Ladyman, Ross and their collaborators (Spurrett is a co-author of two chapters, Collier of one) begin their book with a ferocious attack on "analytic metaphysics", as it is currently practiced. Their opening blast claims that contemporary analytic metaphysics 'contributes nothing to human knowledge': its practitioners are 'wasting their talents', and the whole enterprise, although 'engaged in by some extremely intelligent and morally serious people, fails to qualify as part of the enlightened pursuit of objective truth, and should be discontinued' (vii). They set out on a 'mission of disciplinary rescue' in the spirit of Hume and the logical positivists, in which a fair proportion of philosophy as currently practiced -- as they realize, their critique applies far beyond the boundaries of metaphysics proper -- will be consigned to the flames.

Region R Question: How many objects — entities, things — are contained in R? Ignore the empty space. Our question might better be put, 'How many material objects does R contain?' Let's stipulate that A, B and C are metaphysical atoms: absolutely simple entities with no parts whatsoever besides themselves. So you don't have to worry about counting a particle's top half and bottom half as different objects. Perhaps they are 'point-particles', with no length, width or breadth. Perhaps they are extended in space without possessing spatial parts (if that is possible). Never mind. We stipulate that A, B and C are perfectly simple. We also stipulate that they are connected as follows. A and B are stuck together in such a way that when a force is applied to one of them, they move together 'as a unit'. Moreover, the two of them together exhibit behavior that neither would exhibit on its own — Perhaps they emit a certain sound, or glow in the dark — whereas C is..

Argument that Q∃ expresses more than one proposition: (1) Q∃ expresses the proposition that Q∃ expresses some proposition that isn’t true. ((E)) (2) If Q ∃ expresses only true propositions, then the proposition that Q ∃ expresses some proposition that isn’t true is true. ((1)) (3) If Q∃ expresses only true propositions, then some proposition expressed by Q∃ is not true. (2, T) (4) Some proposition expressed by Q ∃ is not true. ((3)) (5) The proposition that Q ∃ expresses some proposition that isn’t true is true. (4, T) (6) Q∃ expresses at least one true proposition. (1,5) (7) Q∃ expresses at least two propositions. (3, 6) (A parallel argument shows that Q∀ expresses both true and false propositions.

This paper lays out a novel proposal about the metaphysical foundations of (non-relativistic) quantum mechanics, which has some elements in common with Everett's “Many Worlds” interpretation and some elements in common with Bohm's ”Pilot Wave” interpretation. The view agrees with the Everettians that the quantum wavefunction can be interpreted be interpreted as a complete description of the world in fundamental terms. But it holds that this truth of this description suffices for the existence of an uncountable plurality of “worlds” of ordinary, non-fundamental objects, where each such “world” corresponds to a mapping of points of time to points of configuration space that obeys that Bohmian “Guidance Equation”.

In 1950, Quine inaugurated a strange new way of talking about philosophy. The hallmark of this approach is a propensity to take ordinary colloquial sentences that all of us utter routinely when we are not thinking about philosophy, or (more often) other sentences that very directly and obviously logically entail such sentences, and treat those sentences (i) as having a clear content, calling for little or no elucidation, and (ii) as proper objects of philosophical controversy. Questions like ‘are there numbers?’ and ‘are there tables?’ were now placed on a par with questions like ‘are there immaterial souls?’ and ‘are there sense-data?’. Of course philosophers have always had a propensity to say things that sound odd to vulgar ears. What was new with Quine was a systematic policty of privileging these kinds of formulations over more distinctively philosophical idioms. Jargon which had been central to the practice of metaphysics—’logical construction’, ’nothing over and above’, ‘reduce’, ‘ground’, ‘in virtue of’, ‘fundamental’, ‘consist in’...—were shifted to a much more peripheral role. The tradition inaugurated by Quine raises some hard interpretative questions for anyone who, like me and Dave, thinks that there is a range of different propositions that people brought up as English-speakers might be tempted to try to get across by uttering one of these sentences. On the one hand, Dave and I agree that the propositions that any ordinary, unphilosophical use of a sentence like ‘there are some free tables at the back of the café’ would be intended to get across are (in many cases) extremely obvious. The idea that when ontologists assert ‘there are no tables’, or treat this claim as calling for serious debate, they are intending to call into question propositions as obvious as that seems implausibly uncharitable. On the other hand, it is also a hallmark of the Quinean tradition that it claims to be using words in their ordinary sense, at least to the extent that (unlike its founder) it is willing to traffic in talk of meanings at all..