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)

Abstract: This paper defends a constraint that any satisfactory decision theory must satisfy. I show how this constraint is violated by all of the decision theories that have been endorsed in the literature that are designed to deal with cases in which opinions or values are represented by a set of functions rather than a single one. Such a decision theory is necessary to account for the existence of what Ruth Chang has called “parity” (as well as for cases in (...) which agents have incomplete preferences or imprecise credences). The problem with the all of the decision theories that have been defended to account for parity is that they are committed to a claim I call unanimity: when all of the functions in the set agree that an agent ought to do A, then an agent ought to do A. A decision theory committed to unanimity violates the constraint I defend in this paper. Thus, if parity exists, a new approach to decision theory is necessary. (shrink)

The Rachels–Temkin spectrum arguments against the transitivity of better than involve good or bad experiences, lives, or outcomes that vary along multiple dimensions—e.g., duration and intensity of pleasure or pain. This paper presents variations on these arguments involving combinations of good and bad experiences, which have even more radical implications than the violation of transitivity. These variations force opponents of transitivity to conclude that something good is worse than something that isn’t good, on pain of rejecting the good altogether. That (...) is impossible, so we must reject the spectrum arguments. (shrink)

Taking a series of colour patches, starting with one that clearly looks red, and making each so similar in colour to the previous one that it looks the same as it, we appear to be able to show that a yellow patch looks red. I ask whether phenomenal sorites paradoxes, such as this, are subject to a unique kind of solution that is unavailable in relation to other sorites paradoxes. I argue that they do not need such a solution, nor (...) do they succumb to one. In particular, I reject the claim made by Fara and Raffman that looks the same is a transitive relation, which would allow us to solve phenomenal sorites paradoxes by denying the possibility of the required kind of sorites series. (shrink)

(No abstract is available for this citation).

It is natural to distinguish between objective and subjective senses of.

I argue that any plausible decision theory for agents with incomplete preferences which obeys the Never Worse Principle will violate Transitivity. The Never Worse Principle says that if one option never does worse than another, you shouldn’t disprefer it. Transitivity says that if you prefer X to Y and you prefer Y to Z, then you should prefer X to Z. Violating Transitivity allows one to be money pumped. Although agents with incomplete preferences are already, in virtue of having incomplete (...) preferences, vulnerable to being money pumped, I argue that the money pump argument for Transitivity is more serious than the one for Completeness. (shrink)

This collection of 17 essays by the author offers a comprehensive theory of mind, encompassing traditional issues of consciousness and free will.

This paper argues for the existence of a fourth positive generic value relation that can hold between two items beyond ‘better than’, ‘worse than’, and ‘equally good’: namely ‘on a par’.

Collective action problems lie behind many core issues in ethics and social philosophy—for example, whether an individual is required to vote, whether it is wrong to consume products that are produced in morally objectionable ways, and many others. In these cases, it matters greatly what we together do, but yet a single individual’s ‘non-cooperative’ choice seems to make no difference to the outcome and also seems to involve no violation of anyone’s rights. Here it is argued that—contrary to influential arguments (...) by Peter Singer, Alastair Norcross, Shelly Kagan, Derek Parfit, and Allan Gibbard—an appeal to the expected consequences of acts cannot deliver plausible verdicts on many of these cases, because individuals often have a probability of making a difference that is sufficiently small to ensure that ‘non-cooperation’ is the option with the greatest expected value, even when consequentialists themselves agree that ‘cooperation’ is required. In addition, an influential argument by Singer, Norcross, and Kagan is shown to be unsound for the claim that in the collective action situations at issue, the expected effect of one individual’s action equals the average effect of everyone’s similar actions. These results have general implications for normative theory, because they undermine the sort of consequentialist explanation of collective action cases that is initially attractive from many theoretical points of view, consequentialist and otherwise. (shrink)

Several philosophers deny that an individual person’s emissions of greenhouse gas do any harm; I call these “individual denialists.” I argue that each individual’s emissions may do harm, and that they certainly do expected harm. I respond to the denialists’ arguments.

There is a well-known moral quandary concerning how to account for the rightness or wrongness of acts that clearly contribute to some morally significant outcome – but which each seem too small, individually, to make any meaningful difference. One consequentialist-friendly response to this problem is to deny that there could ever be a case of this type. This paper pursues this general strategy, but in an unusual way. Existing arguments for the consequentialist-friendly position are sorites-style arguments. Such arguments imagine varying (...) a subject’s predicament bit by bit until it is clear that a relevant difference has been achieved. The arguments offered in this paper are structurally different, and do not rely on any sorites series. For this reason, they are not vulnerable to objections that have been leveled against the sorites-style arguments. (shrink)

Moral puzzles about actions which bring about very small or what are said to be imperceptible harms or benefits for each of a large number of people are well known. Less well known is an argument by Warren Quinn that standard theories of rationality can lead an agent to end up torturing himself or herself in a completely foreseeable way, and that this shows that standard theories of rationality need to be revised. We show where Quinn's argument goes wrong, and (...) apply this to the moral puzzles. (shrink)

It is commonly held that rational preferences must be acyclic. There have, however, been cases that have been put forward as counterexamples to this view. This paper focuses on the following question: If the counterexamples are compelling and rational preferences can be cyclic, what should we conclude about the presumed acyclicity of the “better than” relation? Building on some revisionary suggestions concerning acyclicity and betterness, I make a case for hanging on to the presumption that “better than” is acyclic even (...) if “is rationally preferred to” is not. As I explain, the divergence my view makes room for does not threaten to make “better than” judgments less relevant to choice than judgments about rational preference. To the contrary, it makes them more relevant. Toward the end of the paper, I extend my results to the relation “is morally better than” in light of the possibility that there might be moral preferability cycles. (shrink)