Epistemological disjunctivism in outline -- Favouring versus discriminating epistemic support -- Radical scepticsim.

Introduction -- Fallibilism -- Contextualism -- Knowledge and reasons -- Justification -- Belief -- The value and importance of knowledge -- Infallibilism or pragmatic encroachment? -- Appendix I: Conflicts with bayesian decision theory? -- Appendix II: Does KJ entail infallibilism?

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.

Princeton University Press, 1974. This book is out of print, but can be downloaded as a pdf file (5 MB).

Testimony is an invaluable source of knowledge. We rely on the reports of those around us for everything from the ingredients in our food and medicine to the identity of our family members. Recent years have seen an explosion of interest in the epistemology of testimony. Despite the multitude of views offered, a single thesis is nearly universally accepted: testimonial knowledge is acquired through the process of transmission from speaker to hearer. In this book, Jennifer Lackey shows that this thesis (...) is false and, hence, that the literature on testimony has been shaped at its core by a view that is fundamentally misguided. She then defends a detailed alternative to this conception of testimony: whereas the views currently dominant focus on the epistemic status of what speakers believe, Lackey advances a theory that instead centers on what speakers say. The upshot is that, strictly speaking, we do not learn from one another's beliefs - we learn from one another's words. Once this shift in focus is in place, Lackey goes on to argue that, though positive reasons are necessary for testimonial knowledge, testimony itself is an irreducible epistemic source. This leads to the development of a theory that gives proper credence to testimony's epistemologically dual nature: both the speaker and the hearer must make a positive epistemic contribution to testimonial knowledge. The resulting view not only reveals that testimony has the capacity to generate knowledge, but it also gives appropriate weight to our nature as both socially indebted and individually rational creatures. The approach found in this book will, then, represent a radical departure from the views currently dominating the epistemology of testimony, and thus is intended to reshape our understanding of the deep and ubiquitous reliance we have on the testimony of those around us. (shrink)

The major divide in contemporary epistemology is between those who embrace and those who reject a priori knowledge. Albert Casullo provides a systematic treatment of the primary epistemological issues associated with the controversy. By freeing the a priori from traditional assumptions about the nature of knowledge and justification, he offers a novel approach to resolving these issues which assigns a prominent role to empirical evidence. He concludes by arguing that traditional approaches to the a priori, which focus primarily on the (...) concepts of necessity and analyticity, are misguided. (shrink)

Virtually all philosophers agree that for a belief to be epistemically justified, it must satisfy certain conditions. Perhaps it must be supported by evidence. Or perhaps it must be reliably formed. Or perhaps there are some other "good-making" features it must have. But does a belief's justification also require some sort of awareness of its good-making features? The answer to this question has been hotly contested in contemporary epistemology, creating a deep divide among its practitioners. Internalists, who tend to focus (...) on scientific or theoretical beliefs as the ideal, insist that such awareness is required for justification. Externalists, who think children's ordinary beliefs in obvious facts are paradigm cases of justified belief, say it isn't required. Michael Bergmann's book offers a decisive refutation of internalism and a sustained defense of externalism. (shrink)

Sometimes appearances provide epistemic support that gets undercut later. In an earlier paper I argued that standard Bayesian update rules are at odds with this phenomenon because they are ‘rigid’. Here I generalize and bolster that argument. I first show that the update rules of Dempster–Shafer theory and ranking theory are rigid too, hence also at odds with the defeasibility of appearances. I then rebut three Bayesian attempts to solve the problem. I conclude that defeasible appearances pose a more difficult (...) and pervasive challenge for formal epistemology than is currently thought. 1 The Challenge for Bayesianism1.1 Updating and experience1.2 The problem1.3 Objections2 The Challenge for Dempster–Shafer Theory2.1 Background on Dempster–Shafer theory2.2 The problem for Dempster–Shafer theory3 The Challenge for Ranking Theory4 The Appeal to Metacognition5 The Appeal to Richer Inputs6 The Appeal to a Generic Underminer7 Conclusion. (shrink)

Conditionalization and Jeffrey Conditionalization cannot simultaneously satisfy two widely held desiderata on rules for empirical learning. The first desideratum is confirmational holism, which says that the evidential import of an experience is always sensitive to our background assumptions. The second desideratum is commutativity, which says that the order in which one acquires evidence shouldn't affect what conclusions one draws, provided the same total evidence is gathered in the end. (Jeffrey) Conditionalization cannot satisfy either of these desiderata without violating the other. (...) This is a surprising problem, and I offer a diagnosis of its source. I argue that (Jeffrey) Conditionalization is inherently anti-holistic in a way that is just exacerbated by the requirement of commutativity. The dilemma is thus a superficial manifestation of (Jeffrey) Conditionalization's fundamentally anti-holistic nature. (shrink)

What is the connection between justification and the kind of consequence relations that are studied by logic? In this essay, I shall try to provide an answer, by proposing a general conception of the kind of inference that counts as justified or rational.

This paper argues that a priori justification is, in principle, compatible with naturalism—if the a priori is understood in a way that is free of the inessential properties that, historically, have been associated with the concept. I argue that empirical indefeasibility is essential to the primary notion of the a priori ; however, the indefeasibility requirement should be interpreted in such a way that we can be fallibilist about apriori-justified claims. This fallibilist notion of the a priori accords with the (...) naturalist’s commitment to scientific methodology in that it allows for apriori-justified claims to be sensitive to further conceptual developments and the expansion of evidence. The fallibilist apriorist allows that an a priori claim is revisable in only a purely epistemic sense. This modal claim is weaker than what is required for a revisability thesis to establish empiricism, so fallibilist apriorism represents a distinct position. (shrink)

This article defends the Fixed Point Thesis: that it is always a rational mistake to have false beliefs about the requirements of rationality. The Fixed Point Thesis is inspired by logical omniscience requirements in formal epistemology. It argues to the Fixed Point Thesis from the Akratic Principle: that rationality forbids having an attitude while believing that attitude is rationally forbidden. It then draws out surprising consequences of the Fixed Point Thesis, for instance that certain kinds of a priori justification are (...) indefeasible and that misleading all-things-considered evidence about rational requirements is impossible. Finally, the Fixed Point Thesis is applied to defend the Right Reasons position on peer disagreement, according to which an agent who has drawn the correct conclusion from her evidence should retain belief in that conclusion even in the face of disagreeing peers. (shrink)

Can known disagreement with our epistemic peers undermine or defeat the justification our beliefs enjoy? Much of the current literature argues for one of two extreme positions on this topic, either that the justification of each person's belief is (fully) defeated by the awareness of disagreement, or that no belief is defeated by this awareness. I steer a middle course and defend a principle describing when a disagreement yields a partial defeater, which results in a loss of some, but not (...) all, of the justification of a belief. I show that the 'no defeater' view is too strong. I also offer reasons for thinking that the 'full defeater' view is similarly mistaken. (shrink)

In his recent book Albert Casullo rejects the claim that if a belief is defeasible by non-experiential evidence then it is defeasible by experiential evidence. This claim is a crucial premise in a simple argument for the experiential defeasibility of a priori justification. I defend the premise against Casullo's objection, the main problem with which is that he does not take into account the evidential role of multiple corroborating sources of testimony. I conclude that the crucial premise is true and (...) that the simple argument is sound; thus many of our a priori justified beliefs are experientially defeasible. (shrink)

Closure for justification is the claim that thinkers are justified in believing the logical consequences of their justified beliefs, at least when those consequences are competently deduced. Many have found this principle to be very plausible. Even more attractive is the special case of Closure known as Single-Premise Closure. In this paper, I present a challenge to Single-Premise Closure. The challenge is based on the phenomenon of rational self-doubt – it can be rational to be less than fully confident in (...) one's beliefs and patterns of reasoning. In rough outline, the argument is as follows: Consider a thinker who deduces a conclusion from a justified initial premise via an incredibly long sequence of small competent deductions. Surely, such a thinker should suspect that he has made a mistake somewhere. And surely, given this, he should not believe the conclusion of the deduction even though he has a justified belief in the initial premise. (shrink)

Sometimes we get what seem to be good reasons for believing that we’ve misevaluated our evidence for a proposition P. In those cases, can we use our evidence for P itself to show that we haven’t misevaluated our evidence for P? I show why doing so appears to employ viciously circular reasoning. However, I then argue that this appearance is illusory in certain cases and that we sometimes can legitimately reason in that way. This claim sheds new light on the (...) nature of epistemic undermining and epistemic circularity. In addition, it has implications for the current debate about the epistemic significance of disagreement. An important and influential position in that debate says that disagreement with others dramatically undermines our justification for a wide range of our opinions (e.g., political, religious, moral, economic, and philosophical opinions). My view on undermining and circularity implies that this position on disagreement rests on a mistake. (shrink)

Consider the skeptic about the external world. Let’s straightaway concede to such a skeptic that perception gives us no conclusive or certain knowledge about our surroundings. Our perceptual justification for beliefs about our surroundings is always defeasible—there are always possible improvements in our epistemic state which would no longer support those beliefs. Let’s also concede to the skeptic that it’s metaphysically possible for us to have all the experiences we’re now having while all those experiences are false. Some philosophers dispute (...) this, but I do not. The skeptic I want to consider goes beyond these familiar points to the much more radical conclusion that our perceptual experiences can’t give us any knowledge or even justification for believing that our surroundings are one way rather than another. (shrink)

There was a long tradition in philosophy according to which good reasoning had to be deductively valid. However, that tradition began to be questioned in the 1960’s, and is now thoroughly discredited. What caused its downfall was the recognition that many familiar kinds of reasoning are not deductively valid, but clearly confer justification on their conclusions. Here are some simple examples.

Taking the inspiration from some points made by Scott Sturgeon and Albert Casullo, I articulate a view according to which an important difference between undermining and overriding defeaters is that the former require the subject to engage in some higher-order epistemic thinking, while the latter don’t. With the help of some examples, I argue that underminers push the cognizer to reflect on the way she formed a belief by challenging the epistemic worthiness of either the source of justification or the (...) specific justificatory process. By contrast, overriders needn’t pose any such challenge. I also consider some problems for the proposed view, and I put forward some possible solutions. Finally, I provide some details on how undermining defeat works in different cases. (shrink)

In Burge 2005, Tyler Burge reads disjunctivism as the denial that there are explanatorily relevant states in common between veridical perceptions and corresponding illusions. He rejects the position as plainly inconsistent with what is known about perception. I describe a disjunctive approach to perceptual experience that is immune to Burge's attack. The main positive moral concerns how to think about fallibility.

In McDowell, I responded to Burge's attack on disjunctivism. In Burge Burge rejects my response. He stands by his main claim that disjunctivism is incompatible with the science of perception, and in a supplementary spirit he argues against the detail of my attempt to defend disjunctivism. Here I explain how disjunctivism is compatible with the science, and I respond to some of Burge's supplementary arguments.

Conciliatory views of disagreement maintain that discovering a particular type of disagreement requires that one make doxastic conciliation. In this paper I give a more formal characterization of such a view. After explaining and motivating this view as the correct view regarding the epistemic significance of disagreement, I proceed to defend it from several objections concerning higher-order evidence made by Thomas Kelly.

The recently offered, Purported counter-Examples to justified, True belief analyses of knowledge are looked at with some care and all found to be either incoherent or inconclusive. It is argued that justified, True belief analyses are based on sound insight into the concept of knowledge. The distinction between having been justified in claiming to know something and actually having known it is used in an effort to get the discussion of knowledge back on the right track.

Recent authors have drawn attention to a new kind of defeating evidence commonly referred to as higher-order evidence. Such evidence works by inducing doubts that one’s doxastic state is the result of a flawed process – for instance, a process brought about by a reason-distorting drug. I argue that accommodating defeat by higher-order evidence requires a two-tiered theory of justification, and that the phenomenon gives rise to a puzzle. The puzzle is that at least in some situations involving higher-order defeaters (...) the correct epistemic rules issue conflicting recommendations. For instance, a subject ought to believe p, but she ought also to suspend judgment in p. I discuss three responses. The first resists the puzzle by arguing that there is only one correct epistemic rule, an Über-rule. The second accepts that there are genuine epistemic dilemmas. The third appeals to a hierarchy or ordering of correct epistemic rules. I spell out problems for all of these responses. I conclude that the right lesson to draw from the puzzle is that a state can be epistemically rational or justified even if one has what looks to be strong evidence to think that it is not. As such, the considerations put forth constitute a non question-begging argument for a kind of externalism. (shrink)

One of the central problems afflicting reductionism in the epistemology of testimony is the apparent fact that infants and small children are not cognitively capable of having the inductively based positive reasons required by this view. Since non-reductionism does not impose a requirement of this sort, it is thought to avoid this problem and is therefore taken to have a significant advantage over reductionism. In this paper, however, I argue that if this objection undermines reductionism, then a variant of it (...) similarly undermines non-reductionism. Thus, considerations about the cognitive capacities of infants and small children do not effectively discriminate between these two competing theories of testimonial justification. (shrink)

Jonathan Kvanvig has argued that what he terms “doxastic” theories of epistemic justification fail to account for certain epistemic features having to do with evidence. I’m going to give an argument roughly along these lines, but I’m going to focus specifically on proper function theories of justification or warrant. In particular, I’ll focus on Michael Bergmann’s recent proper function account of justification, though the argument applies also to Alvin Plantinga’s proper function account of warrant. The epistemic features I’m concerned about (...) are experiences that should generate a believed defeater but don’t. I’ll argue that proper functionalism as it stands cannot account for the epistemic effects of these defeating experiences—or, at least, that it can only do so by embracing a deeply implausible view of our cognitive faculties. I’ll conclude by arguing that the only plausible option Bergmann has for modifying his theory undercuts the consideration that motivates proper functionalism in the first place. (shrink)

In a recent and interesting paper “Experientially Defeasible A Priori Justification,” Joshua Thurow argues that many a priori justified beliefs are defeasible by experience. The argument takes the form of an objection against Albert Casullo’s recent book, A Priori Justification, where Casullo, according to Thurow, denies that if a justified belief is non-experientially defeasible, then that belief is also experientially defeasible. This paper critically examines Thurow’s two arguments in the first two sections I–II. In the last section, III, an alternative (...) line of argument for Thurow’s thesis is suggested that employs other parts of the framework that Casullo provides—especially the thesis of overdetermination of justification. It will be argued that the prospects for this suggestion are brighter than for bothof Thurow’s arguments. (shrink)

Many views rely on the idea that it can never be rational to have high confidence in something like, “P, but my evidence doesn’t support P.” Call this idea the “Non-Akrasia Constraint”. Just as an akratic agent acts in a way she believes she ought not act, an epistemically akratic agent believes something that she believes is unsupported by her evidence. The Non-Akrasia Constraint says that ideally rational agents will never be epistemically akratic. In a number of recent papers, the (...) Non-Akrasia Constraint has been called into question. The goal of this paper is to defend it... for the most part. (shrink)

It is widely assumed that justification is defeasible, e.g. that under certain conditions counterevidence removes prior justification of beliefs. In this paper I will first (sect. 1) explain why this feature of justification poses a prima facie problem for reliabilism. I then will try out different reliabilist strategies to deal with the problem. Among them I will discuss conservative strategies (sect. 2), eliminativist stragies (sect. 3) and revisionist strategies (sect. 4). In the final section I will present an improved revisionist (...) approach to defeaters that is able to overcome the main shortcomings of the other approaches. (shrink)

Today, many philosophers think that perceptual experiences are conscious mental states with representational content and phenomenal character. Subscribers to this view often go on to construe experience more precisely as a propositional attitude sui generis ascribing sensible properties to ordinary material objects. I argue that experience is better construed as a kind of belief ascribing 'phenomenal' properties to such objects. A belief theory of this kind deals as well with the traditional arguments against doxastic accounts as the sui generis view. (...) Moreover, in contrast to sui generis views, it can quite easily account for the rational or reason providing role of experience. (shrink)

Evidentialism is the thesis that a person is justified in believing a proposition iff the person's evidence on balance supports that proposition. In discussing epistemological issues associated with disagreements among epistemic peers, some philosophers have endorsed principles that seem to run contrary to evidentialism, specifying how one should revise one's beliefs in light of disagreement. In this paper, I examine the connection between evidentialism and these principles. I argue that the puzzles about disagreement provide no reason to abandon evidentialism and (...) that there are no true general principles about justified responses to disagreement other than the general evidentialist principle. I then argue that the puzzles about disagreement are primarily puzzles about the evidential impact of higher - order evidence – evidence about the significance or existence of ordinary, or first- order, evidence. I conclude by arguing that such higher - order evidence can often have a profound effect on the justification of first- order beliefs. (shrink)

Duncan Pritchard has recently defended a view he calls ‘epistemological disjunctivism’, largely inspired by John McDowell. I argue that Pritchard is right to associate the view with McDowell, and that McDowell’s ‘inference-blocking’ argument against the sceptic succeeds only if epistemological disjunctivism is accepted. However, Pritchard also recognises that epistemological disjunctivism appears to conflict with our belief that genuine and illusory experiences are indistinguishable (the ‘distinguishability problem’). Since the indistinguishability of experiences is the antecedent in the inference McDowell intends to block, (...) I suggest that his argument rests on an inconsistent set of premises. In support of this, I show that Pritchard’s response to the distinguishability problem is incompatible with the conclusion of the ‘inference-blocking’ argument, and that the response available in McDowell’s work relies on a mistaken conception of fallibility. Either McDowell must deny the sceptic’s premise that perceptual experiences are indistinguishable, or he must give up his conclusion that perceptual warrant can be indefeasible. (shrink)

For some of us, the defeasibility theory of knowledge remains the most plausible approach to the Gettier Problem. Epistemological fashion and faded memories notwithstanding, persuasive objections to the theory are very hard to find. The most impressive of those objections to the theory that have hitherto gone unanswered are examined and rejected here. These are objections put forward by Richard Feldman, Richard Foley, and John Turri. While these are all interesting, the objection recently put forward by Turri is, we think, (...) by far, the most serious threat to the theory that we have seen in a long time. A successful reply to it requires a surprising amount of care, as it turns out. If tenable, Turri's objection deals a devastating blow to the theory developed by Roderick Chisholm, Keith Lehrer, Peter Klein, Marshall Swain, Risto Hilpinen, John Pollock, and Paul Moser, among others. Under scrutiny, however, the threat proves illusory. It results from inattention to a crucial, but relatively subtle, aspect of.. (shrink)

How much should your confidence in your beliefs be shaken when you learn that others – perhaps ‘epistemic peers’ who seem as well-qualified as you are – hold beliefs contrary to yours? This article describes motivations that push different philosophers towards opposite answers to this question. It identifies a key theoretical principle that divides current writers on the epistemology of disagreement. It then examines arguments bearing on that principle, and on the wider issue. It ends by describing some outstanding questions (...) that thinking about this issue raises. (shrink)

Sometimes we get evidence of our own epistemic malfunction. This can come from finding out we’re fatigued, or have been drugged, or that other competent and well-informed thinkers disagree with our beliefs. This sort of evidence seems to seems to behave differently from ordinary evidence about the world. In particular, getting such evidence can put agents in a position where the most rational response involves violating some epistemic ideal.

Certain situations seem to call for acknowledging the possibility that one’s own beliefs are biased or distorted. On the other hand, certain sorts of epistemic self-doubts (such as ‘I believe it’s raining, but it’s not’) seem paradoxical. And some have put forth epistemic principles requiring rational agents to regard their own credences as so-called ‘expert functions’. This paper examines the question of whether rationality requires agents to respect their own credences in a way in which they need not respect the (...) credences of others. (shrink)

How should one react when one has a belief, but knows that other people—who have roughly the same evidence as one has, and seem roughly as likely to react to it correctly—disagree? This paper argues that the disagreement of other competent inquirers often requires one to be much less confident in one’s opinions than one would otherwise be.

How much should your confidence in your beliefs be shaken when you learn that others – perhaps 'epistemic peers' who seem as well-qualified as you are – hold beliefs contrary to yours? This article describes motivations that push different philosophers towards opposite answers to this question. It identifies a key theoretical principle that divides current writers on the epistemology of disagreement. It then examines arguments bearing on that principle, and on the wider issue. It ends by describing some outstanding questions (...) that thinking about this issue raises. (shrink)

It appears to have gone unnoticed in the literature that Pollock's widely endorsed analysis of evidential defeat entails a remarkably strong symmetry principle, according to which, for any three propositions D, E and H, if both E and D provide a reason to believe H, then D is a defeater for E's support for H if and only if, in turn, E is a defeater for D's support for H. After illustrating the counterintuitiveness of this constraint, a simple, more suitable, (...) alternative to the Pollockian account is offered. (shrink)

A review of Albert Casullo's "A Priori Justification" (Oxford University Press).