Several philosophers have proposed Knowledge-Based Decision Theories (KDTs)—theories that require agents to maximize expected utility as yielded by utility and probability functions that depend on the agent’s knowledge. Proponents of KDTs argue that such theories are motivated by Knowledge-Reasons norms that require agents to act only on reasons that they know. However, no formal derivation of KDTs from Knowledge-Reasons norms has been suggested, and it is not clear how such norms justify the particular ways in which KDTs relate knowledge and (...) rational action. In this paper, I suggest a new axiomatic method for justifying KDTs and providing them with stronger normative foundations. I argue that such theories may be derived from constraints on the relation between knowledge and preference, and that these constraints may be evaluated relative to intuitions regarding practical reasoning. To demonstrate this, I offer a representation theorem for a KDT proposed by Hawthorne and Stanley (2008) and briefly evaluate it through its underlying axioms. (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)

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)

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)

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)

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)

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)

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)

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)

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.

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)

The paper discusses some ways in which the phenomenon of borderline cases may be thought to bear on the traditional philosophical idea that certain domains of facts are fully open to our view. The discussion focusses on a very influential argument (due to Tim Williamson) to the effect that, roughly, no such domains of luminous facts exist. Many commentators have felt that the vagueness unavoidably inherent in the description of the facts that are best candidates for being luminous plays an (...) illicit role in the argument. The paper investigates this issue by centring around the idea that vagueness brings with itself borderline cases, and that these in turn generate absence of a fact of the matter and hence epistemically benign lack of knowledge. It is argued that, given the possibility of absence of a fact of the matter, the idea of luminosity should be reformulated using the notion of determinacy, and that the resulting reformulation is not immediately subject to the original anti-luminosity argument. However, it is shown that the specific understanding of determinacy required by this strategy validates a new argument against the reformulated version of luminosity. Moreover, reflection on the connection between mistake and absence of a fact of the matter offers another argument against such version, with the surprising upshot that, granting the soundness of the original anti-luminosity argument, not even the determinacy of a certain fact would guarantee its knowability. (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)

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)

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)

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.