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 second volume in the _Blackwell Brown Lectures in Philosophy_, this volume offers an original and provocative take on the nature and methodology of philosophy. Based on public lectures at Brown University, given by the pre-eminent philosopher, Timothy Williamson Rejects the ideology of the 'linguistic turn', the most distinctive trend of 20th century philosophy Explains the method of philosophy as a development from non-philosophical ways of thinking Suggests new ways of understanding what contemporary and past philosophers are doing.

When I take off my glasses, the world looks blurred. When I put them back on, it looks sharpedged. I do not think that the world really was blurred; I know that what changed was my relation to the distant physical objects ahead, not those objects themselves. I am more inclined to believe that the world really is and was sharp-edged. Is that belief any more reasonable than the belief that the world really is and was blurred? I see more (...) accurately with my glasses on than off, so visual appearances when they are on have some cognitive priority over visual appearances when they are off. If I must choose which kind of visual appearance to take at face value, I will choose the sharp-edged look. But what should I think when I see a mist, which looks very blurred however well I am seeing? Indeed, why choose to take any of the looks at face value? Why not regard all the choices as illegitimate projections of ways of seeing the world onto the world itself? (shrink)

In this paper we discuss how Causal Decision Theory should be modified to handle a class of problematic cases involving deterministic laws. Causal Decision Theory, as it stands, is problematically biased against your endorsing deterministic propositions (for example it tells you to deny Newtonian physics, regardless of how confident you are of its truth). Our response is that this is not a problem for Causal Decision Theory per se, but arises because of the standard method for assessing the truth of (...) certain counterfactuals. The truth of deterministic laws is `modally fragile' on the standard semantics for counterfactuals: if determinism is true and you were to do otherwise, the laws would be different. We provide two ways of avoiding this problem: 1) supplement the standard semantics for counterfactuals with impossible worlds, or 2) introduce rigid designators into the description of problematic decision situations. We argue that both of these approaches are well-motivated and can be readily incorporated into Lewisian Causal Decision Theory. (shrink)

The paper clarifies and defends the orthodox view that counterfactual conditionals with impossible antecedents are vacuously true against recent criticisms. It argues that apparent counterexamples to orthodoxy result from uncritical reliance on a fallible heuristic used in the processing of conditionals. A comparison is developed between such counterpossibles and vacuously true universal generalizations.

Two opposing tendencies in the philosophy of language go by the names of ‘referentialism’ and ‘inferentialism’ respectively. In the crudest version of the contrast, the referentialist account of meaning gives centre stage to the referential semantics for a language, which is then used to explain the inference rules for the language, perhaps as those which preserve truth on that semantics (since a referential semantics for a language determines the truth-conditions of its sentences). By contrast, the inferentialist account of meaning gives (...) centre stage to the inference rules for the language, which are then used to explain its referential semantics, perhaps as the semantics on which the rules preserve truth. On pain of circularity, we cannot combine both directions of explanation. (shrink)

Timothy Williamson gives an original and provocative treatment of deep metaphysical questions about existence, contingency, and change, using the latest resources of quantified modal logic. Contrary to the widespread assumption that logic and metaphysics are disjoint, he argues that modal logic provides a structural core for metaphysics.

Imagine a philosophy conference in Presocratic Greece. The hot question is: what are things made of? Followers of Thales say that everything is made of water, followers of Anaximenes that everything is made of air, and followers of Heraclitus that everything is made of fire. Nobody is quite clear what these claims mean, and some question whether the founders of the respective schools ever made them. But amongst the groupies there is a buzz about all the recent exciting progress. The (...) mockers and doubters make plenty of noise too. They point out that no resolution of the dispute between the schools is in sight. They diagnose Thales, Anaximenes and Heraclitus as suffering from a tendency to overgeneralize. We can intelligibly ask what bread is made of, or what houses are made of, but to ask what things in general are made of is senseless, some suggest, because the question is posed without any conception of how to verify an answer; language has gone on holiday. Paleo-pragmatists invite everyone to relax, forget their futile pseudo-inquiries and do something useful instead. (shrink)

Metaphysical modalities are definable from counterfactual conditionals, and the epistemology of the former is a special case of the epistemology of the latter. In particular, the role of conceivability and inconceivability in assessing claims of possibility and impossibility can be explained as a special case of the pervasive role of the imagination in assessing counterfactual conditionals, an account of which is sketched. Thus scepticism about metaphysical modality entails a more far-reaching scepticism about counterfactuals. The account is used to question the (...) significance of the distinction between a priori and a posteriori knowledge. (shrink)

This chapter aims to attempt no more than to make some informal and unsystematic remarks on the transformation of analytic philosophy. It deals with a few sketchy remarks on the historiography of recent analytic philosophy. Writing in 1981, David Lewis described “a reasonable goal for a philosopher” as bringing one’s opinions into stable equilibrium. A natural comparison is between Lewis’s Quinean or at least post‐Quinean methodology and the methodology of Peter Strawson, Quine’s leading opponent from the tradition of ordinary language (...) philosophy. Analytic epistemology provides a good case study of the philosophical application of Gricean pragmatics outside the philosophy of language. On Michael Dummett picture of the history of philosophy, Descartes had made epistemology first philosophy, the engine for the rest of philosophy, and then Frege had replaced epistemology by the philosophy of language as first philosophy. The chapter suggests that philosophy sometimes already uses an abductive methodology and ought to use it more in the future. (shrink)

Knowledge and its Limits presents a systematic new conception of knowledge as a kind of mental stage sensitive to the knower's environment. It makes a major contribution to the debate between externalist and internalist philosophies of mind, and breaks radically with the epistemological tradition of analyzing knowledge in terms of true belief. The theory casts new light on such philosophical problems as scepticism, evidence, probability and assertion, realism and anti-realism, and the limits of what can be known. The arguments are (...) illustrated by rigorous models based on epistemic logic and probability theory. The result is a new way of doing epistemology and a notable contribution to the philosophy of mind. (shrink)

The book records a series of philosophical exchanges between its authors, amounting to a debate extended over more than fifteen years. Its subject matter is the nature and scope of reason. A central case at issue is basic logical knowledge, and the justification for basic deductive inferences, but the arguments range far more widely, at stake the distinctions between analytic and synthetic, and between a priori and a posteriori. The discussion naturally involves problems about the conditions for linguistic understanding and (...) competence, and what it might be to grasp a concept or to have an intuition. Since reason is central to philosophical method, there are associated implications for how philosophy itself works, or should work. In particular, the discussion raises fundamental concerns about how to approach epistemology. -/- . (shrink)

A history of the many different forms that the linguistic turn took would be a history of much of twentieth‐century philosophy. A. J. Ayer was the first holder of the Wykeham Chair to take the linguistic turn. Michael Dummett makes clear that he takes this concern with language to be what distinguishes “analytical philosophy” from other schools, the first‐personal inaccessibility of the language of thought makes such a version of the linguistic turn methodologically very different from the traditional ones. Even (...) within what is usually considered analytic philosophy of mind, much work violates the two tenets of conceptual philosophy. One might try to see in contemporary metaphysics a Quinean breakdown of divisions between philosophy and the natural sciences. Historians of philosophy on the grand scale may be too Whiggish or Hegelian to regard the linguistic or conceptual turn as merely a false turning from which philosophy is withdrawing that it recognizes its mistake. (shrink)

This chapter analyzes the logical structure of Edmund Gettier‐style thought experiments. The discussion can be generalized to many imaginary counterexamples that have been deployed against philosophical analyses and theories in ways more or less similar to Gettier’s. The background working hypothesis is that his thought experiments are paradigmatic, in the sense that if any thought experiments can succeed in philosophy, his do: thus to determine whether Gettier’s thought experiments succeed is in effect to determine whether there can be successful thought (...) experiments in philosophy. Gettier presents his specific counterexamples to the target analysis through short fictional narratives, in the present tense indicative, with fictional uses of proper names, all introduced by “suppose that.” One manifestation of the influence of past experience on epistemological judgments may be cross‐cultural variation in verdicts on thought experiments, including the Gettier case. (shrink)

A case in point is Frank Jackson’s talk of “conceptual possibility” and “conceptual necessity.” He writes as if the issue between us is the relative methodological priority for philosophy of conceptual modalities and metaphysical modalities. In addition to the uncritical reliance on conceptual modality, another fallacy is surfacing. Paul Boghossian developed an epistemology of logic based on understanding‐assent links corresponding to fundamental rules of logic. His paradigm was modus ponens: a necessary condition for understanding “if” was supposed to be willingness (...) to assent to inferences by modus ponens involving “if.” Boghossian objects that Simon’s tolerance of assent to gappy statements undermines the presumption that he is assenting to them as true. In Nenad Miscevic paper, such competencies are postulated for the linguistic, spatial‐geometric, mathematical, metaphysical, epistemological, and moral domains. Thus Miscevic auxiliary modularity‐independent characterization offers little help in demarcating a useful category of intuition. (shrink)

One proposal is to generalize UAl to define an epistemological notion of analyticity: a sentence s is analytic just in case, necessarily, whoever understands s assents to s. This chapter considers what is epistemically available simply on the basis of linguistic and conceptual competence. It deals with a provisional sketch of some obstacles to extracting epistemological consequences from understanding‐assent links and of some attempts to overcome them. A trickier question is whether such possibilities of an illusion of understanding have negative (...) epistemological repercussions for cases of genuine understanding, since a skeptical doubt can arise for the subject in the latter cases too as to whether the understanding is not an illusion. Quine’s epistemological holism in “Two Dogmas” undermines his notorious later claim about the deviant logician’s predicament: “when he tries to deny the doctrine he only changes the subject”. (shrink)

Moore’s sympathies are anti‐realist. As an example of an antirealist account of truth, he gives what he calls “the Wittgensteinian View” of truth for mathematical discourse. In attempting to show how to “sidestep certainly apparently decisive objections” to the Wittgensteinian View, Moore acquiesces in the charge that it makes the consistency of a mathematical theory a matter of stipulation: we adopt a rule “that guarantees the consistency of Peano Arithmetic.” Moore’s main concern is the defensibility of anti‐realist view of philosophical (...) discourse. In “Williamson’s Philosophy of Philosophy”, Paul Horwich defends the idea that the proper business of philosophy is clarification rather than systematic theory‐building. In political philosophy, it would be hard to mount a credible defense of some system of government without considering what effects it causally explains. In terms of Diego Marconi’s clear version of Wittgenstein’s account, it is straightforward to explain why it is no longer a live option for so many philosophers. (shrink)

In most intellectual disciplines, assertions are supposed to be backed by evidence. Mathematicians have proofs, biochemists have experiments, and historians have documents. The dialectical nature of philosophical inquiry exerts general pressure to psychologize evidence, and so distance it from the non‐psychological subject matter of the inquiry. Evidence Neutrality has no more force in philosophy than in other intellectual disciplines: philosophers are lucky if they achieve as much certainty as the natural sciences, without quixotic aspirations for more. Skepticism about perception typically (...) narrows one’s evidential base to one’s present internal mental state. Justifying a philosophical method by appeal only to Epistemic Conservativism ignores crucial epistemological distinctions concerning the relevant beliefs: it is like justifying scientific methodology without giving any information as to what evidence is required in its application. The reflective equilibrium account, as usually understood, already assigns a proto‐evidential role to at least one kind of non‐psychological fact. (shrink)

Experimental results can in principle undermine the procedures of any intellectual community, by revealing patterns of variation in its members’ judgments that are hard to reconcile with the supposition that those judgments are even moderately reliable. Armchair philosophy typically involves the evaluation of constant stimuli, such as the scenario of a thought experiment, often presented by a written description, so in that respect Shanteau’s paper is encouraging. Jonathan Weinberg does not attempt to specify the psychological or social nature of armchair (...) philosophy. Jonathan M. Weinberg, Chad Gonnerman, Cameron Buckner, and Joshua Alexander describe the target of the experimentalist critique as “analytic philosophy’s longstanding practice of deploying armchair intuitive judgments about cases”. WGBA do try to identify some relevant differences between thought experiments and other cognitive tasks in philosophy in terms drawn from the scientific literature on expertise. The phrase “experimental philosophy” can mean many things. (shrink)

This chapter argues that the ordinary cognitive capacity to handle counterfactual conditionals carries with it the cognitive capacity to handle metaphysical modality. It aims to illustrate with examples our cognitive use of counterfactual conditionals, and sketches an epistemology for such conditionals. The chapter explains how they subsume metaphysical modality, and assesses the consequences for the distinction between a priori and a posteriori knowledge. It discusses the relation between metaphysical possibility and the restricted kinds of possibility that seem more relevant to (...) ordinary life. Philosophers’ ascriptions of metaphysical modality are far more deeply rooted in our ordinary cognitive practices than most skeptics about it realize. Many philosophers are more confident in their judgments about more or less realistic thought experiments in epistemology and moral philosophy than about more radically strange ones in metaphysics. Philosophical controversy will naturally make the unclear cases salient. (shrink)

Lemmon and Scott introduced the notion of a modal system's providing the rule of disjunction. No consistent normal extension of KB provides this rule. An alternative rule is defined, which KDB, KTB, and other systems are shown to provide, while K and other systems provide the Lemmon-Scott rule but not the alternative rule. If S provides the alternative rule then either —A is a theorem of S or A is whenever A -> ΠA is a theorem; the converse fails. It (...) is suggested that systems with this property are appropriate for handling sorites paradoxes, where D is read as 'clearly*. The S4 axiom fails in such systems. (shrink)

No existing normative decision theory adequately handles risk. Expected Utility Theory is overly restrictive in prohibiting a range of reasonable preferences. And theories designed to accommodate such preferences (for example, Buchak's (2013) Risk‐Weighted Expected Utility Theory) violate the Betweenness axiom, which requires that you are indifferent to randomizing over two options between which you are already indifferent. Betweenness has been overlooked by philosophers, and we argue that it is a compelling normative constraint. Furthermore, neither Expected nor Risk‐Weighted Expected Utility Theory (...) allow for stakes‐sensitive risk‐attitudes—they require that risk matters in the same way whether you are gambling for loose change or millions of dollars. We provide a novel normative interpretation of Weighted‐Linear Utility Theory that solves all of these problems. (shrink)

Many philosophers consciously seek conceptual connections, conceptual necessities, conceptual truths, and conceptual analyses. Philosophers of mind and language dispute whether there is a language of thought; whatever the answer, it is no conceptual truth. Moral and political philosophers and philosophers of art appeal to empirically discovered human cognitive limitations, and so on. This chapter examines a variety of attempts to develop a metaphysical account of analyticity. It also explores epistemological account of analyticity, also with negative results. The overall upshot is (...) that philosophical truths are analytic at most in senses too weak to be of much explanatory value or to justify conceiving contemporary philosophy in terms of a linguistic or conceptual turn. A core of philosophical truths may indeed be modal‐analytic. Some philosophers seek to articulate necessary truths without essential reliance on indexicals; if they succeed, the sentences they produce are modal‐analytic. (shrink)

This chapter explores some general aspects of the tension between one’s role as a believer and one’s role as an appraiser of oneself as a believer in philosophy. The proposal is to replace true belief by knowledge in a principle of charity constitutive of content. Knowledge maximization need not make the ascription of knowledge come too cheap. By contrast, Davidson’s principle of charity gives good marks to an interpretation for having Stone Age people assent to many truths of quantum mechanics, (...) if it happens to fit the compositional structure of their language. Perhaps the underlying worries about knowledge maximization can be captured in a more abstract form. A subtler attempt to extract knowledge from Davidson’s principle of charity exploits beliefs that one knows. Knowledge maximization implies that our ancestors had some primitive knowledge as soon as they had some primitive beliefs; it is not as though archaeology suggests otherwise. (shrink)

This chapter presents a question closely related to the problem of vagueness, because it looks like a paradigm of a philosophical question that is implicitly but not explicitly about thought and language. It is useful to look at some proposals and arguments from the vagueness debate, for two reasons. First, they show why the original question is hard, when taken at face value. Second, they show how semantic considerations play a central role in the attempt to answer it, even though (...) it is not itself a semantic question. Some philosophers deny the relevance of formal semantic theories to vague natural languages. Some contemporary metaphysicians appear to believe that they can safely ignore formal semantics and the philosophy of language because their interest is in a largely extra‐mental reality. Conceptions of logic and mathematics as somehow trivial or non‐substantial have not been vindicated by any clear explanation of the relevant sense of “trivial” or “non‐substantial.”. (shrink)

In “Knowing the Intuition and Knowing the Counterfactual”, Jonathan Ichikawa objects that this misrepresents the thought experiment as more accident‐prone than it really is. Ichikawa could take over exactly the formalization of the Gettier argument that the book recommends counterfactual and all. Michael Martin suggests that the idea of progress in a discipline, although applicable to mathematics and the natural sciences, fails to fit some of the humanities, such as history, so that we should not be too surprised if it (...) also fails to fit philosophy. Martin is more willing to countenance progress for individual philosophers than for the discipline as a whole. The crucial difference, Brandom argues, is that only the human can do things like reasoning from “That’s red” to “That’s colored.” Metaphysics is back in fashion, at least in the analytic tradition that dominates English‐speaking philosophy and is growing rapidly across the rest of the world too. (shrink)

The use of mathematical models in philosophy is largely neutral over the extent of experimental input. They can figure in an entirely armchair methodology, but they can also play the sort of role they do in physics, economics, and other natural and social sciences. Andrea Bianchi’s description of the starting‐point of philosophy as “empirical data” also suggests a special connection between philosophy and the natural sciences. Many contemporary philosophers describe themselves as naturalists. Naturalists typically criticize some traditional forms of philosophy (...) as insufficiently scientific, because they ignore experimental tests. Naturalism tries to condense the scientific spirit into a philosophical theory. Penelope Maddy rightly emphasizes the weirdness of the idea, found in some contemporary internalist epistemology, that introspection has epistemic priority over perception, but her central objection is to demands on the Plain Inquirer to justify her methods “from scratch.”. (shrink)

Epistemic logics for subjects of bounded rationality are in effect nonnormal modal logics. Admissible rules are of interest in such logics. However, the usual methods for establishing admissibility employ Kripke models and are therefore inappropriate for nonnormal logics. This paper extends syntactic methods for a variety of rules and nonnormal logics. In doing so it answers a question asked by Chellas and Segerberg.

A concept of informational equivalence between relations is explicated to generalize some suggestions by Geach. It is shown that two relations are informationally equivalent if and only if each can be defined in terms of the other without the use of quantifiers. It is shown that there is a general method for listing the ./-place relations informationally equivalent to an arbitrary given /-place relation if and only if i (...) the invariants of the group of invertible quantifier-free definitions, for / =j. Quantifier-free definition is contrasted with general first-order definition by means of an example of two first-order interdefinable relations which are not interdefined by any pair of mutually inverse first-order definitions. (shrink)

This paper is concerned with formal solutions to the lottery paradox on which high probability defeasibly warrants acceptance. It considers some recently proposed solutions of this type and presents an argument showing that these solutions are trivial in that they boil down to the claim that perfect probability is sufficient for rational acceptability. The argument is then generalized, showing that a broad class of similar solutions faces the same problem. An argument against some formal solutions to the lottery paradox The (...) argument generalized Some variations Adding modalities Anticipated objections. (shrink)

Rational agents face choices, even when taking seriously the possibility of determinism. Rational agents also follow the advice of Causal Decision Theory (CDT). Although many take these claims to be well-motivated, there is growing pressure to reject one of them, as CDT seems to go badly wrong in some deterministic cases. We argue that deterministic cases do not undermine a counterfactual model of rational deliberation, which is characteristic of CDT. Rather, they force us to distinguish between counterfactuals that are relevant (...) and ones that are irrelevant for the purposes of deliberation. We incorporate this distinction into decision theory to develop ‘Selective Causal Decision Theory’, which delivers the correct recommendations in deterministic cases while respecting the key motivations behind CDT. (shrink)