Timothy Williamson has a marvelously precise account of epistemic justification in terms of knowledge and probability. I argue that the account runs aground on certain cases involving the probability values 0 and 1.

Since its appearance over a decade ago, Timothy Williamson's anti-luminosity argument has come under sustained attack. Defenders of the luminous overwhelmingly object to the argument's use of a certain margin-for-error premise. Williamson himself claims that the premise follows easily from a safety condition on knowledge together with his description of the thought experiment. But luminists argue that this is not so: the margin-for-error premise either requires an implausible interpretation of the safety requirement on knowledge, or it requires other equally implausible (...) assumptions. In this paper I bolster the margin-for-error premise against these attacks by recasting Williamson's own two-part defence, the first part intended to work on the assumption that there is no constitutive connection between the phenomenal and the doxastic, and the second intended to work without this assumption. Pace various luminists, I argue that the appeals to safety needed for Williamson's two-part defence are plausible. I also argue that all that is needed to generate the margin-for-error premise from these safety conditions is an empirical assumption about the kinds of creatures we are: that is, creatures whose beliefs are structured by certain dispositions. By recasting the anti-luminosity argument in this way, we can understand what is really at stake in the debate about luminosity: that is, whether we are luminous. (shrink)

The world is said to contain crystal balls whenever the present carries news of the as-yet-undetermined parts of the future. Many philosophers believe that crystal balls are metaphysically possible. In this essay, I argue that they are not. Whether crystal balls are possible matters, for at least two reasons. The first is epistemological. According to a simple, user-friendly chance norm for credence, which I call the Present Principle, agents are rationally required to conform their credences to their expectations of the (...) present chances, deferring to the present chances as they would to an expert. I would like to defend the Present Principle since its truth would do much to simplify the relation between chance and credence. But the Present Principle is counterexample-free, and hence defensible, only if crystal balls are impossible. The second reason is decision-theoretic. The problem of crystal balls is one of the main objections to causal decision theory. But crystal ball cases can be counterexample to causal decision theory only if crystal balls are possible, and, as I argue, crystal balls are not possible. (shrink)

Questions about the transparency of evidence are central to debates between factive and non-factive versions of mentalism about evidence. If all evidence is transparent, then factive mentalism is false, since no factive mental states are transparent. However, Timothy Williamson has argued that transparency is a myth and that no conditions are transparent except trivial ones. This paper responds by drawing a distinction between doxastic and epistemic notions of transparency. Williamson's argument may show that no conditions are doxastically transparent, but it (...) fails to show that no conditions are epistemically transparent. Moreover, this reinstates the argument from the transparency of evidence against factive mentalism. (shrink)

Whether some condition is equivalent to a conjunction of some conditions has been a major issue in analytic philosophy. Examples include: knowledge, acting freely, causation, and justice. Philosophers have striven to offer analyses of these, and other concepts, by showing them equivalent to such a conjunction. Timothy Williamson offers a number of arguments for the idea that knowledge is ‘prime’, hence not equivalent to or composed by some such conjunction. I focus on one of his arguments: the requirement that such (...) conjuncts must be freely recombinable. Although there has been a great deal of discussion of Williamson's arguments, the flaw I describe has gone unnoticed. Williamson's argument is expressed in terms of conditions, and cases of the condition. Does the condition include specific information, or is the specific information only part of the case? His argument equivocates between more and less general specifications of the conditions. Once this distinction is clarified, his argument can be seen to be vitiated by this conflation. Neither option yields a sound argument for Williamson's desired conclusion. (shrink)

I show that accepting Moss’s claim that features of a rational agent’s credence function can constitute knowledge, together with the claim that a rational agent should only act on the basis of reasons that he knows, predicts and explains evidential decision theory’s failure to recommend the right choice for the Newcomb problem. The Newcomb problem can be seen, in light of Moss’s suggestion, as a manifestation of a Gettier case in the domain of choice. This serves as strong evidence for (...) both Moss’s claim and the knowledge-based action approach. (shrink)

In this article I focus on some unduly neglected common-sense considerations supporting the view that one's evidence is the propositions that one knows. I reply to two recent objections to these considerations.

The Preface Paradox is often discussed for its implications for rational belief. Much less discussed is a variant of the Preface Paradox for knowledge. In this paper, I argue that the most plausible closure-friendly resolution to the Preface Paradox for Knowledge is to say that in any given context, we do not know much. I call this view “Socraticism”. I argue that Socraticism is the most plausible view on two accounts—(1) this view is compatible with the claim that most of (...) our knowledge ascriptions are true, and (2) provided that (1) is true, the costs of accepting Socraticism are much less than the costs of accepting any other resolution to the Paradox. I argue for (1) in Section 2 by developing a question-sensitive contextualist model for knowledge that shows how Socraticism is compatible with the claim that most of our knowledge ascriptions are true. I also argue how this contextualist model can achieve this result where other contextualist models fail. I then consider other closure-friendly solutions to the paradox in Section 3 and show how accepting those solutions forces us to give up a number of plausible epistemic principles. (shrink)

Visual experiences seem to exhibit phenomenological particularity: when you look at some object, it – that particular object – looks some way to you. But experiences exhibit generality too: when you look at a distinct but qualitatively identical object, things seem the same to you as they did in seeing the first object. Naïve realist accounts of visual experience have often been thought to have a problem with each of these observations. It has been claimed that naïve realist views cannot (...) account for the generality of visual experiences, and that the naïve realist explanation of particularity has unacceptable implications for self- knowledge: the knowledge we have of the character of our own experiences. We argue in this paper that neither claim is correct: naïve realism can explain the generality of experiences, and the naïve realist explanation of particularity raises no problems for our self-knowledge. (shrink)

The idea that knowledge is conceptually related to practical reasoning is becoming increasingly popular. In defending this idea, philosophers have been relying on a conception of practical reasoning that drastically deviates from one which has been more traditionally advocated in analytic philosophy and which assigns no special role to knowledge. This paper argues that these philosophers have failed to give good reasons for thinking that the conception of practical reasoning they have been assuming is the right one, and that hence (...) they have been rash to conclude that there is a conceptual relation between knowledge and practical reasoning. (shrink)

The idea that knowledge is conceptually related to practical reasoning is becoming increasingly popular. In defending this idea, philosophers have been relying on a conception of practical reasoning that drastically deviates from one which has been more traditionally advocated in analytic philosophy and which assigns no special role to knowledge. This paper argues that these philosophers have failed to give good reasons for thinking that the conception of practical reasoning they have been assuming is the right one, and that hence (...) they have been rash to conclude that there is a conceptual relation between knowledge and practical reasoning. (shrink)

While there is no shortage of philosophical literature discussing knowledge by acquaintance, there is a surprising dearth of work about theories of epistemic justification based on direct acquaintance. This paper explores a basic framework for a thoroughly general account of epistemic justification by acquaintance. I argue that this approach to epistemic justification satisfies two importance aspects of justification. After sketching how the acquaintance approach can meet both objective and subjective aspects for epistemic justification, I will outline how this general account (...) of justification by acquaintance can be applied to the analysis of justification for many types of beliefs. Finally, some of the objections to the acquaintance approach will be considered and answered. (shrink)

Over the years I’ve written many papers defending an idiosyncratic version of interest-relative epistemology. This book collects and updates the views I’ve expressed over those papers. -/- Interest-relative epistemologies all start in roughly the same way. A big part of what makes knowledge important is that it rationalises action. But for almost anything we purportedly know, there is some action that it wouldn’t rationalise. I know what I had for breakfast, but I wouldn’t take a bet at billion to one (...) odds about it. Knowledge has practical limits. The first idiosyncratic feature of my version of interest-relative epistemology is how those limits are identified. Other interest-relative philosophers typically say that the limits have to do with stakes; in high stakes situations knowledge goes away. That’s no part of my view. I think knowledge goes away in long odds situations. High stakes situations are almost always are long odds situations, for reasons to do with the declining marginal utility of money. But the converse isn’t true. On my view, knowledge often goes away in cases where it is trivial to check before action. This idea, that interests matter in long odds cases, and not just in high stakes cases, is the main constant in what I’ve written on interest-relativity over the years. -/- But there are three other respects in which the view I’m going to set out and defend in this book is very different from the view I set out in older papers. -/- I used to identify the practical limits on knowledge with cases where relying on the purported knowledge would get the wrong answer. I focused, that is, on the outputs of inquiry. Knowledge goes away if relying on it would lead one to make a mistake. I now think I was looking at the wrong end of inquiry. Knowledge goes away if the thinker starts conducting an inquiry where the purported knowledge is an inappropriate starting point, and inappropriate for the special reason that it might be false. Now one way we can tell that something is a bad starting point is that starting there will mean we end up at the wrong place. But it’s not the only way. Sometimes a bad starting point will lead to the right conclusion for the wrong reasons. As the Nyāya philosophers argued, rational inquiry starts with knowledge. If it would be irrational to start this inquiry with a particular belief, that belief isn’t knowledge. -/- Not all inquiries are practical inquiries, but many are. And practical inquiries are usually going to be at the center of attention in this book. But what is someone trying to figure out when they conduct a practical inquiry? I used to think that they were trying to figure out which option maximised expected utility, and to a first approximation identified knowledge with those things one could conditionalise on without changing the option that maximised expected utility. As noted in the previous paragraph, I no longer think that we can identify knowledge with what doesn’t change our verdicts. But more importantly, I no longer think that expected utility maximisation is as central to practical inquiry as I once did. There are some theoretical reasons from game theory that raise some doubts about expected utility maximisation. Weak dominance reasoning is part of our theory of rational choice, and can’t be modelled as expected utility maximisation. Perhaps some kinds of equilibrium seeking are parts of practical inquiry, and can’t be modelled as expected utility maximisation. But there are also very practical reasons to think that practical inquiry doesn’t aim at expected utility maximisation. When there are a lot of very similar options - think about selecting a can from a supermarket shelf - and it’s more trouble than it’s worth to figure out which of them maximises expected utility, it’s best to ignore the differences between them and just pick. As I’ll argue in Chapter 6, this makes a big difference to how interests and knowledge interact. -/- In the version of interest-relativity that I’m defending here, everything in epistemology is interest-relative. Knowledge, rational belief, and evidence are all interest-relative. But they are all interest-relative in slightly different ways. The main aim here is to defend the interest-relativity of knowledge. A common objection to interest-relative theories of knowledge is that they can’t be extended into theories of all the things we care about in epistemology. Here I try to meet that challenge. The way I do so is a little messy. It would be nice if there was some part of epistemology that’s interest-invariant, as I used to think, or if all the interest-relative notions were interest-relative in the same way, as other interest-relative epistemologists argue. For better or worse, that’s not the view I’m defending. Interests matter throughout epistemology, and we just have to go case by case to figure out how and why they matter. (shrink)

According to the knowledge view of evidence notoriously defended by Timothy Williamson (2000), for any subject, her evidence consists of all and only her propositional knowledge (E=K). Many have found (E=K) implausible. However, few have offered arguments against Williamson’s positive case for (E=K). In this paper, I propose an argument against Williamson’s positive case in favour of (E=K). Central to my argument is the possibility of the knowledge of necessary truths. I also draw some more general conclusions concerning theorizing about (...) evidence. (shrink)

Timothy Williamson’s anti luminosity argument has received considerable attention. Escaping unnoticed, though, is a strikingly similar argument from David Hume. This paper highlights some of the arresting parallels between Williamson’s reasoning and Hume’s that will allow us to appreciate more deeply the plausibility of Williamson’s reasoning and to understand how, following Hume, we can extend this reasoning to undermine the “luminosity” of simple necessary truths. More broadly the parallels help us to identify a common skeptical predicament underlying both arguments, which (...) we shall call “the quarantine problem”. The quarantine problem expresses a deep skepticism about achieving any exalted epistemic state. Further, the perspective gained by the quarantine problem allows us to easily categorize existing responses to Williamson’s anti luminosity argument and to observe the deficiencies of those responses. In sum, the quarantine problem reveals the deeply fallibilistic nature of whatever knowledge we may possess. (shrink)

A traditional line of inquiry in epistemology tried to analyze the concept of knowledge into its constituent components. In virtue of understanding these alleged more basic concepts, such as truth, justification, and belief, it was hoped that a complete and informative theory of knowledge would emerge. According to the revolutionary approach advocated here, one which originates in Timothy Williamson's Knowledge and Its Limits, better success can be achieved by reversing this conceptual analysis structure by taking knowledge as the fundamental explanatory (...) tool in epistemological theorizing. I defend the view that this knowledge-theoretic approach exceeds the explanatory value of its conceptual analysis competitor in the sense that the best explanations of epistemologically significant phenomena are appropriately expressed in terms of knowledge per se. (shrink)

Defenders of the Knowledge Argument contend that physicalism is false because knowing all the physical truths is not sufficient to know all the truths about the world. In particular, proponents of the Knowledge Argument claim that physicalism is false because the truths about the character of conscious experience are not knowable from the complete set of physical truths. This dissertation is a defense of the Knowledge Argument. Chapter one characterizes what physicalism is and provides support for the claim that if (...) knowing all the physical truths is not sufficient to know all the truths about the world, then physicalism is false. In chapter two, I defend the claim that knowing all the physical truths is not sufficient for knowing all the truths about the world. In addition to mounting a prima facie case for the knowledge intuition, I present and defend an epistemology grounded in direct acquaintance to provide a more substantive argument to accept it. Chapters three through five address the physicalist objections to the Knowledge Argument. The first set of objections advocates that knowing all the physical truths is, in fact, sufficient for knowing all the truths about the world. The next set of objections admits that there is some sense in which knowing all the physical truths is not sufficient for knowing all the truths about the world. However, these objections maintain that the kind of knowledge that is absent from the complete set of physical truths is know-how or knowledge by acquaintance, and not factual or propositional knowledge. The final set of objections maintain that the kind of propositional knowledge that is left out of the complete set of physical truths is compatible with physicalism. My response to these objections is part of advancing my prima facie case for the Knowledge Argument. The final chapter addresses a structural question that pertains to the Knowledge Argument. Some philosophers have maintained that the structure of the Knowledge Argument invites a kind of self-refutation of any systematic account of reality. The concern is that the Knowledge Argument proves too much, and that the dualist who uses the argument to refute physicalism risks the argument defeating his own position. I will argue that the Knowledge Argument does not refute dualism. (shrink)