In the world of philosophy of science, the dominant theory of confirmation is Bayesian. In the wider philosophical world, the idea of inference to the best explanation exerts a considerable influence. Here we place the two worlds in collision, using Bayesian confirmation theory to argue that explanatoriness is evidentially irrelevant.

The claim of this paper is that the everyday functions of knowledge make most sense if we see knowledge as contrastive. That is, we can best understand how the concept does what it does by thinking in terms of a relation “a knows that p rather than q.” There is always a contrast with an alternative. Contrastive interpretations of knowledge, and objections to them, have become fairly common in recent philosophy. The version defended here is fairly mild in that there (...) is no suggestion that we cannot think in terms of a simpler not explicitly contrastive relation “a knows that p.” Some, for instance Schaffer (2005) and Karjalainen and Morton (2003), have hinted that this stronger possibility may be right. But all that I am arguing now is that facts that are easily expressed in contrastive terms are vital to understanding why we need the concept of knowledge. In a piece that is in some ways a companion to this one ("Contrastivism" in Duncan Pritchard and Sven Bernecker, eds. The Routledge Companion to Epistemology. Routledge 2010, 513-522), I give a general survey of theories of contrastive knowledge and the differences between them. (shrink)

Some philosophers argue that we are justified in rejecting skepticism because it is explanatorily inferior to more commonsense hypotheses about the world. Focusing on the work of Jonathan Vogel, I show that this “abductivist” or “inference to the best explanation” response rests on an impoverished explanatory framework which ignores the explanatory gap between an object's having certain properties and its appearing to have those properties. Once this gap is appreciated, I argue, the abductivist strategy is defeated.

The standard contextualist solution to the skeptical paradox is intended to provide a way to retain epistemic closure while avoiding the excessive modesty of radical skepticism and the immodesty of Moorean dogmatism. However, contextualism’s opponents charge that its solution suffers from epistemic immodesty comparable to Moorean dogmatism. According to the standard contextualist solution, all contexts where an agent knows some ordinary proposition to be true are contexts where she also knows that the skeptical hypotheses are false. It has been hoped (...) that contrastivist theories of knowledge can mirror the contextualist solution while avoiding this epistemic immodesty. I review the main problems for contrastive closure and argue that none of the arguments currently in the literature pose an insurmountable problem for the contrastivist solution. However, I argue that contrastivist theories of knowledge, like their contextualist rivals, are indeed committed to epistemic immodesty. (shrink)

Abductivists claim that explanatory considerations (e.g., simplicity, parsimony, explanatory breadth, etc.) favor belief in the external world over skeptical hypotheses involving evil demons and brains in vats. After showing how most versions of abductivism succumb fairly easily to obvious and fatal objections, I explain how rationalist versions of abductivism can avoid these difficulties. I then discuss the most pressing challenges facing abductivist appeals to the a priori and offer suggestions on how to overcome them.

This paper argues for a solution to a problem that contrastivism faces. The problem is that contrastivism cannot preserve closure, in spite of claims to the contrary by its defenders. The problem is explained and a response developed.

Does G. E. Moore know that he has hands? Yes, says the dogmatist: Moore’s hands are right before his eyes. No, says the skeptic: for all Moore knows he could be a brain-in-a-vat. Yes and no, says the contrastivist: yes, Moore knows that he has hands rather than stumps; but no, Moore does not know that he has hands rather than vat-images of hands. The dogmatist and the skeptic suppose that knowledge is a binary, categorical relation: s knows that p. (...) The contrastivist says that knowledge is a ternary, contrastive relation: s knows that p rather than q. (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)

Contextualism treats ‘knows’ as an indexical that denotes different epistemic properties in different contexts. Contrastivism treats ‘knows’ as denoting a ternary relation with a slot for a contrast proposition. I will argue that contrastivism resolves the main philosophical problems of contextualism, by employing a better linguistic model. Contextualist insights are best understood by contrastivist theory.

In virtue of what are we justified in employing the rule of inference Modus Ponens? One tempting approach to answering this question is to claim that we are justified in employing Modus Ponens purely in virtue of facts concerning meaning or concept-possession. In this paper, we argue that such meaning-based accounts cannot be accepted as the fundamental account of our justification.

Something about this argument sounds funny. As we’ll see, though, it takes some care to identify exactly what Moore has done wrong. Iwill assume that Moore knows premise (2) to be true. One could inquire into how he knows it, and whether that knowledge can be defeated; but Iwon’t. I’ll focus instead on what epistemic relations Moore has to premise (1) and to his conclusion (3). It may matter which epistemic relations we choose to consider. Some philosophers will diagnose Moore’s (...) argument using Contextualist machinery. They’ll say. (shrink)

John Hawthorne’s marvelous book contains a wealth of arguments and insights based on an impressive knowledge and understanding of contemporary discussion. We can address only a small aspect of the topic. In particular, we will offer our own answers to two questions about knowledge that he discusses.

The dominant response to this problem of the criterion focuses on the alleged requirement that we need to know a belief source is reliable in order for us to acquire knowledge by that source. Let us call this requirement, “The KR principle”.

This paper addresses a problem about epistemic warrant. The problem is posed by philosophical arguments for externalism about the contents of thoughts, and similarly by philosophical arguments for architecturalism about thinking, when these arguments are put together with a thesis of first person authority. In each case, first personal knowledge about our thoughts plus the kind of knowledge that is provided by a philosophical argument seem, together, to open an unacceptably ‘non-empirical’ route to knowledge of empirical facts. Furthermore, this unwelcome (...) prospect of transferring a ‘non-empirical’ warrant from premises about our own mental states and about philosophical theory to a conclusion about external environment or internal architecture seems to depend upon little more than the possibility of knowledge by inference. (The use of the scare-quoted term ‘non-empirical’ is explained a couple of paragraphs further on.). (shrink)

In this paper, I defend epistemological contrastivism—the view that propositional knowledge is a three-place, contrastive relation between an agent, a proposition and a contrast term—against two a priori arguments recently offered by Mikkel Gerken for the conclusion that intuitive judgements exhibiting a contrast effect on knowledge ascriptions are false positives. I show that the epistemic argument for false positives begs the question against contrastivism by assuming the independently implausible claim that knowledge of a contrastive proposition always presupposes knowledge of a (...) related ordinary proposition. This claim is apparently also presupposed by the doxastic argument for false positives, the conclusion of which, I argue, is not only perfectly compatible with epistemological contrastivism but also heavily dependent on a de dicto construal of the relevant knowledge ascriptions. (shrink)

The view that propositional knowledge is knowledge of facts is prima facie rather appealing, especially for realistically minded philosophers, but it is difficult to square with the referential opacity of knowledge attributions of the form ‘S knows that p’. For how could Lois Lane know that Superman can fly and ignore that Clark Kent can fly if knowledge is a two-place relation between an agent and a fact and the fact that Superman can fly just is the fact that Clark (...) Kent can fly? Giorgio Volpe reviews some attempts to tackle the problem and then proposes a new solution which exploits the contrastivist claim that knowledge is a three-place relation between an agent, a fact and a contrast. (shrink)

A common response to radical skeptical challenges to our knowledge of the external world has been that there are explanatory reasons (e.g., simplicity, coherence, explanatory power, conservatism) for favoring commonsense explanations of our sensory experiences over skeptical explanations. Despite the degree of visibility this class of response has enjoyed, it has often been viewed with skepticism [sic] by the epistemological community because of concerns about the epistemic merits of explanatory reasoning. I argue that skeptical challenges that employ skeptical hypotheses presuppose (...) central explanationist tenets and that this fact should raise one’s estimation of the strength of explanationist responses to skepticism. (shrink)

_ Source: _Volume 7, Issue 4, pp 258 - 271 This contribution to the symposium on Annalisa Coliva’s _Extended Rationality_ is largely sympathetic with the moderate view of the structure of epistemic warrant which is defended in the book. However, it takes issue with some aspects of Coliva’s Wittgenstein-inspired ‘hinge epistemology’, focussing especially on her conception of propositional warrant, her treatment of epistemic closure, her antirealist conception of truth, and the significance of her answer to so-called Humean scepticism.

This paper raises a problem for contrastivist accounts of knowledge. It is argued that contrastivism fails to succeed in providing a modest solution to the sceptical paradox—i.e. one according to which we have knowledge of a wide range of ordinary empirical propositions whilst failing to know the various anti-sceptical hypotheses entailed by them—whilst, at the same time, retaining a contrastivist version of the closure principle for knowledge.

When epistemologists talk about knowledge, the discussions traditionally include only a small class of other epistemic notions: belief, justification, probability, truth. In this paper, we propose that epistemologists should include an additional epistemic notion into the mix, namely the notion of assuming or taking for granted.

How should the contrastivist formulate closure? That is, given that knowledge is a ternary contrastive state Kspq (s knows that p rather than q), how does this state extend under entailment? In what follows, I will identify adequacy conditions for closure, criticize the extant invariantist and contextualist closure schemas, and provide a contrastive schema based on the idea of extending answers. I will conclude that only the contrastivist can adequately formulate closure.

Epistemic Angst offers a completely new solution to the ancient philosophical problem of radical skepticism—the challenge of explaining how it is possible to have knowledge of a world external to us. Duncan Pritchard argues that the key to resolving this puzzle is to realize that it is composed of two logically distinct problems, each requiring its own solution. He then puts forward solutions to both problems. To that end, he offers a new reading of Wittgenstein's account of the structure of (...) rational evaluation and demonstrates how this provides an elegant solution to one aspect of the skeptical problem. Pritchard also revisits the epistemological disjunctivist proposal that he developed in previous work and shows how it can effectively handle the other aspect of the problem. Finally, he argues that these two antiskeptical positions, while superficially in tension with each other, are not only compatible but also mutually supporting. The result is a comprehensive and distinctive resolution to the problem of radical skepticism, one that challenges many assumptions in contemporary epistemology. (shrink)

Most solutions to the skeptical paradox about justified belief assume closure for justification, since the rejection of closure is widely regarded as a non-starter. I argue that the rejection of closure is not a non-starter, and that its problems are no greater than the problems associated with the more standard anti-skeptical strategies. I do this by sketching a simple version of the unpopular strategy and rebutting the three best objections to it. The general upshot for theories of justification is that (...) it is not a constraint on such theories that we must somehow have justification to believe that we are not massively deceived. (shrink)

In the contemporary expanding literature on transmission failure and its connections with issues such as the Closure principle, the nature of perceptual warrant, Moore’s proof of an external world and the effectiveness of Humean scepticism, it has often been assumed that there is just one kind of it: the one made familiar by the writings of Crispin Wright and Martin Davies. Although it might be thought that one kind of failure is more than enough, Davies has recently challenged this view: (...) apparently, there are more ways in heaven and earth that warrant can fail to transmit across valid inference from one (set of) belief(s) to another, than have been dreamt of in philosophy so far. More specifically, Davies thinks that a second kind of transmission failure has to be countenanced. He connects each kind of failure of transmission of warrant with two different kinds of epistemic project, respectively, and with the exploration of whether the current dispute between conservatives such as Wright, and liberals such as Jim Pryor, on the nature of perceptual warrant, would have a bearing on them. I point out why Davies’s second kind of transmission failure is indeed no such thing. I then move on to canvass another kind of transmission failure, different from the one studied by both Wright and Davies, and dependent on an alternative conception of the structure of empirical warrants, which I dub “moderatism”. I then consider how this alternative notion of transmission failure fares with respect to Moore’s proof, its relationship with Wright’s kind of transmission failure and with the Closure principle. In closing, I defend it from criticisms that can be elicited from Pryor’s recent work. (shrink)

In the recent literature on Moore's Proof of an external world, it has emerged that different diagnoses of the argument's failure are prima facie defensible. As a result, there is a sense that the appropriateness of the different verdicts on it may depend on variation in the kinds of context in which the argument is taken to be a move, with different characteristic aims. In this spirit, Martin Davies has recently explored the use of the argument within two different epistemic (...) projects called respectively ‘deciding what to believe’ and ‘settling the question’. Depending on which project is in hand, according to Davies, the diagnoses of its failure—if indeed it fails—will differ. I believe that, by introducing the idea that the effectiveness of a valid argument may be epistemic project-relative, Davies has pointed the way to an important reorientation of the debates about Moore's Proof. But I wish to take issue with much of the detail of his proposals. I argue that Davies's characterization of his two projects is misleading (§1), and his account of their distinction defective (§2). I then canvass some suggestions about how it may be improved upon and about how further relevant kinds of epistemic projects in which Moore's argument may be taken to be a move can be characterized, bringing out how each of these projects impinges differently on the issue of the Proof's failure and of its diagnosis (§§3 and 4). In conclusion (§5) I offer an overview of the resulting terrain. (shrink)

He then argues that (1), (2) and (3) constitute an inconsistent triad as follows (1991, p. 15): Suppose (1) that Oscar knows a priori that he is thinking that water is wet. Then by (2), Oscar can simply deduce E, using premisses that are knowable a priori, including the premiss that he is thinking that water is wet. Since Oscar can deduce E from premisses that are knowable a priori, Oscar can know E itself a priori. But this contradicts (3), (...) the assumption that E cannot be known a priori. Hence (1), (2), and (3) are inconsistent. McKinsey’s conclusion is that ‘anti-individualism is inconsistent with privileged access’ (ibid.). (shrink)

First published in 1987. Routledge is an imprint of Taylor & Francis, an informa company.

General contrastivism holds that all claims of reasons are relative to contrast classes. This approach applies to explanation (reasons why things happen), moral philosophy (reasons for action), and epistemology (reasons for belief), and it illuminates moral dilemmas, free will, and the grue paradox. In epistemology, contrast classes point toward an account of justified belief that is compatible with reliabilism and other externalisms. Contrast classes also provide a model for Pyrrhonian scepticism based on suspending belief about which contrast class is relevant. (...) This view contrasts with contextualism, invariantism, and Schaffer's contrastivism. (shrink)

_ Source: _Volume 7, Issue 4, pp 217 - 234 The paper presents the key themes of my _Extended Rationality: A Hinge Epistemology_. It focuses, in particular, on the moderate account of perceptual justification, the constitutive response put forward against Humean skepticism, epistemic relativism, the closure principle, the transmission of warrant principle, as well as on the applications of the extended rationality view to the case of the principle of the uniformity of nature, testimony, and the justification of basic laws (...) of inference. (shrink)

I argue that its appearing to you that P does not provide justification for believing that P unless you have independent justification for the denial of skeptical alternatives – hypotheses incompatible with P but such that if they were true, it would still appear to you that P. Thus I challenge the popular view of ‘dogmatism,’ according to which for some contents P, you need only lack reason to suspect that skeptical alternatives are true, in order for an experience as (...) of P to justify belief that P. I pursue three lines of objection to dogmatism, having to do with probabilistic reasoning, considerations of future or hypothetically available justification, and epistemic circularity. I briefly sketch a fall-back position which avoids the problems raised. (shrink)

This paper contributes to the current debate about radical scepticism and the structure of warrant. After a presentation of the standard version of the radical sceptic’s challenge, both in its barest and its more refined form, three anti-sceptical responses, and their respective commitments, are being identified: the Dogmatist response, the Conservativist response and the Dretskean response. It is then argued that both the Dretskean and the Conservativist are right that the anti-sceptical hypothesis cannot inherit any perceptual warrants from ordinary propositions (...) about the environment—and so the Dogmatist response founders. However, if this is so Epistemic Closure lacks any clear rationale. There is therefore good reason to agree with both the Dretskean and the Dogmatist that perceptual warrants for ordinary propositions about the environment are enough in order for those propositions to enjoy a positive epistemic status—and so the Conservativist response founders. However, the Conservativist is nonetheless right that a warrant for the anti-sceptical hypothesis is needed. For contrary to what much of the recent literature suggests, the radical sceptic need not appeal to Epistemic Closure in order to cast doubt on the legitimacy of our beliefs in ordinary propositions about the environment: there is a Pyrrhonian version of scepticism that, though equally radical, is consistent with failure of Epistemic Closure. For this reason, the Dretskean response is insufficient to answer scepticism. (shrink)

The scandal to philosophy and human reason, wrote Kant, is that we must take the existence of material objects on mere faith . In contrast, the skeptical paradox that has scandalized recent philosophy is not formulated in terms of faith, but rather in terms of justification, warrant, and entitlement. I argue that most contemporary approaches to the paradox (both dogmatist/liberal and default/conservative) do not address the traditional problem that scandalized Kant, and that the status of having a warrant (or justification) (...) that is derived from entitlement is irrelevant to whether we take our beliefs on mere faith. For, one can have the sort of warrant that most contemporary anti-skeptics posit while still taking one’s belief on mere faith. An alternative approach to the traditional problem is sketched, one that still makes use of contemporary insights about “entitlement.”. (shrink)

_ Source: _Volume 7, Issue 4, pp 281 - 295 The paper contains the replies to the comments made by Alan Millar, Yuval Avnur, Giorgio Volpe, and Maria Baghramian on my _Extended Rationality: A Hinge Epistemology_. It addresses, in particular, the nature of perceptual justification, the truth of hinges, my response to Humean skepticism and the issue of epistemic relativism.