A general trend in recent philosophical and empirical work aims to undermine various traditional claims regarding the distinctive nature of self-knowledge. So far, however, this work has not seriously threatened the Cartesian claim that (at least some) self-knowledge is immune to the sort of sceptical problem that seems to afflict our knowledge of the external world. In this paper I carry this trend further by arguing that the Cartesian claim is false. This is done by showing that a (...) familiar sceptical argument that targets my knowledge of the external world can be adapted to target my belief that I exist, along with any of my self-knowledge that I know entails my own existence. Thus, my self-knowledge and my knowledge of the external world are subject to the same sort of sceptical problem. (shrink)

In this thesis I give a response to external world scepticism. I first argue that scepticism arises when we accept that it is an empirical question whether I am in a sceptical scenario, that is, a scenario in which my beliefs are coherent, and yet my empirical beliefs are false. The idea that it is an empirical question whether I am in a sceptical scenario gets its plausibility from the realist claim that our empirical beliefs have (...) an objective subject matter. I then attempt to give a response to scepticism that is compatible with this realist claim. Three promising responses to scepticism are considered, but are found to be inadequate. Seeing why these responses are inadequate helps us to appreciate some of the conditions on an adequate response to scepticism. By drawing on the work of Donald Davidson I develop a response to scepticism that is compatible with the realist claim, and that meets these conditions. According to this response, when we get clear about the concept of belief we see that sceptical scenarios are a conceptual impossibility. Thus, just as it is not an empirical question whether I am a married bachelor, it is not an empirical question whether I am in a sceptical scenario, and the argument for scepticism breaks down. (shrink)

In a recent paper McCain (2012) argues that weak predictivism creates an important challenge for external world scepticism. McCain regards weak predictivism as uncontroversial and assumes the thesis within his argument. There is a sense in which the predictivist literature supports his conviction that weak predictivism is uncontroversial. This absence of controversy, however, is a product of significant plasticity within the thesis, which renders McCain’s argument worryingly vague. For McCain’s argument to work he either needs a stronger (...) version of weak predictivism than has been defended within the literature, or must commit to a more precise formulation of the thesis and argue that weak predictivism, so understood, creates the challenge to scepticism that he hopes to achieve. The difficulty with the former is that weak predictivism is not uncontroversial in the respect that McCain’s argument would require. I consider the prospects of saving McCain’s argument by committing to a particular version of weak predictivism, but find them unpromising for several reasons. (shrink)

The canonical version of external world scepticism has the following structure: Premise1: If P knows that she is not a brain in a vat, then P does not have knowledge of the external world. Premise2: P does not know that she is not a brain in a vat. Conclusion: Therefore, P does not have knowledge of the external world. Some philosophers attack premise1 by denying the underlying closure principle. I will investigate possible argumentations (...) for and against premise2. I will show that premise2 is only true if additional internalistic conditions are fulfilled. I will conclude that the canonical version of the argument is inadequate and that premise1 must be replaced by a stronger internalistic premise. After presenting the adequate argument, I will argue that this internalistic premise contradicts the closure principle underlying premise1. I will conclude that external world scepticism can only hold if the closure principle is rejected. (shrink)

In this paper, I compare and contrast two kinds of scepticism, Cartesian scepticism about the external world and Quinean scepticism about meaning. I expose Quine's metaphysical claim that there are no facts of the matter about meaning as a sceptical response to a sceptical problem regarding the possibility of our knowledge of meanings. I argue that this sceptical response is overkill; for the sceptical problem about our knowledge of meanings may receive a treatment similar to (...) the naturalistic treatment Quine himself offered for the problem of our knowledge of the external world. Further, I suggest that a naturalistic treatment of Quinean meaning scepticism may fare better than Quine's own naturalistic treatment of external world scepticism. (shrink)

This thesis has three parts. In the first part, the author defends the coherence of Cartesian scepticism about the external world. In particular, the author contends that such scepticism survives attacks from Descartes himself, as well as from W.V.O. Quine, Robert Nozick, Alvin Goldman, and David Armstrong. It follows that Cartesian scepticism remains intact. In the second part of this thesis, the author contends that the semantic or content externalisms of Hilary Putnam and Tyler Burge (...) do not refute Cartesian scepticism about the external world. In particular, he argues that Putnam and Burge do not make good their respective externalist cases against scepticism, and that they beg the question against that position. The author concludes that semantic or content externalism is important against such scepticism. In the third part of this thesis, the author addresses the mind, and suggests that Descartes, by offering his cogito argument, also offers a theory of thought content, which he then supports with his substance dualism. He suggests that Descartes does not succeed with any of his arguments here, although his theory of thought content is still plausible. To remedy this, the author discusses the versions of narrow meaning or content offered by Jerry Fodor and Colin McGinn, and defends a version of such meaning or content that presupposes that semantic or content externalism is false. The author lastly follows Donald Davidson, and argues for a version anomalous monism, which he contends is a theory that shows how semantic or content internalism might be true. (shrink)

This article develops a logical (or semantic) response to scepticism about the existence of an external world. Specifically, it is argued that any doubt about the existence of an external world can be proved to be false, but whatever appears to be doubt about the existence of an external world that _cannot_ be proved to be false is nonsense, insofar as it must rely on the assertion of something that is logically impossible. The (...) article further suggests that both G. E. Moore and Ludwig Wittgenstein worked towards the same solution but left their work unfinished. (shrink)

One of the most important and perennially debated philosophical questions is whether we can have knowledge of the external world. Butchvarov here considers whether and how skepticism with regard to such knowledge can be refuted or at least answered. He argues that only a direct realist view of perception has any hope of providing a compelling response to the skeptic and introduces the radical innovation that the direct object of perceptual, and even dreaming and hallucinatory, experience is always (...) a material object, but not necessarily one that actually exists. This leads him to a metaphysics in which reality is ultimately constructed by human decisions out of objects that are ontologically more basic but which cannot be said in themselves to be either real or unreal. (shrink)

The paper investigates the senses in which the world may be thought external, and argues that none of them supports doubt about the possibility of knowledge of the world. Scepticism sometimes depends on certain erroneous conceptions of perception, especially those which lead to belief in 'inner, representational states'. How we perceive things depends on the satisfaction of certain general conditions--on what concepts we have, on the kind of senses we have, and so on a kind of (...) anthropocentricity; but this does not prevent objectivity, even in the case of secondary qualities. (shrink)

Heidegger says concerning the question of the possibility of a proof of the existence of an external world that ‘the “scandal of philosophy” is not that this proof has yet to be given, but that such proofs are expected and attempted again and again’. Heidegger thinks this because our being is in the world, and this is something which Descartes for one failed to appreciate. I am not concerned here to answer the question whether Heidegger's own views (...) on these matters will do, though I think that they will not. Indeed they might well be said to beg the question at issue, in that Heidegger starts from the presumption that we are actually in the world, even if we are not in it in the way in which the tree in the garden is. Another way of reacting to Heidegger would be to say that he does not treat the fact and force of scepticism seriously enough when he makes that presumption. After all, it is possible for us to raise sceptical doubts about the existence of a world apart from ourselves, while it is not possible for the tree in the garden to act similarly. Hence, even if we make the presumption that we are in the world, as Heidegger insists, we are in it in a way that leaves untouched the possibility of sceptical doubts about what that world and our being in it are like. It might, logically, be the case, for example, that the world consists of just me and that my being in the world is no more than for me just to exist. In other words, my being in the world does not directly entail that there exists a world apart from me. (shrink)

The existence of objects external to the mind is a proof-condition for the type of object demonstration Moore provided in his famous lecture. Affirming the existence of objects external to the mind is just a way of saying that one person can show (present, demonstrate) something to another to prove it is so, to prove it exists, Demonstrations like that are conclusive and immune to scepticism.

McDermid clarifies the nature of Santayana’s scepticism by examining his response to the traditional sceptical problem of the external world. The chapter explains in what sense we can regard Santayana as a sceptic and in what sense Santayana is a critic of the sceptical method promulgated by Descartes.

This paper is a sympathetic critique of the argument that Reichenbach develops in Chap. 2 of Experience and Prediction for the thesis that sense experience justifies belief in the existence of an external world. After discussing his attack on the positivist theory of meaning, I describe the probability ideas that Reichenbach presents. I argue that Reichenbach begins with an argument grounded in the Law of Likelihood but that he then endorses a different argument that involves prior probabilities. I (...) try to show how this second step in Reichenbach’s approach can be strengthened by using ideas that have been developed recently for understanding causation in terms of the idea of intervention. (shrink)

Moore's proof of an external world is a piece of reasoning whose premises, in context, are true and warranted and whose conclusion is perfectly acceptable, and yet immediately seems flawed. I argue that neither Wright's nor Pryor's readings of the proof can explain this paradox. Rather, one must take the proof as responding to a sceptical challenge to our right to claim to have warrant for our ordinary empirical beliefs, either for any particular empirical belief we might have, (...) or for belief in the existence of an external world itself. I show how Wright's and Pryor's positions are of interest when taken in connection with Humean scepticism, but that it is only linking it with Cartesian scepticism which can explain why the proof strikes us as an obvious failure. (shrink)

A new reading of G.E. Moore's ‘Proof of an External World’ is offered, on which the Proof is understood as a unique and essential part of an anti-sceptical strategy that Moore worked out early in his career and developed in various forms, from 1909 until his death in 1958. I begin by ignoring the Proof and by developing a reading of Moore's broader response to scepticism. The bulk of the article is then devoted to understanding what role (...) the Proof plays in Moore's strategy, and how that role is played. (shrink)

In the first experiment, I exhibit unreliable judgment about the primeness or divisibility of four-digit numbers, in contrast to a seeming Excel program. In the second experiment, I exhibit an imperfect memory for arbitrary-seeming three-digit number and letter combinations, in contrast to my seeming collaborator with seemingly hidden notes. In the third experiment, I seem to suffer repeated defeats at chess. In all three experiments, the most straightforward interpretation of the experiential evidence is that something exists in the universe that (...) is superior in the relevant respects – theoretical reasoning (about primes), memorial retention (for digits and letters), or practical reasoning (at chess) – to my own solipsistically-conceived self. (shrink)

본고는 흄의 외부 세계 현존 문제에 대한 비판적 재구성을 꾀한다. 흄은 그의 주저 『인성론』 1권, 4부, 2절 논의(“감관들에 관련된 회의주의에 대해서Of Scepticism with Regard to the Senses”)에서 지금까지도 계속 철학자들의 골치를 썩이는 이 문제를 다룬다. 하지만 흄의 논의는 필요 이상으로 장황하고 복잡다단하며 불분명한 탓에, 일단 먼저 그가 제시한 논증을 차례대로 좇아서 살피기 전에 논증의 전 구조를 망라하는 그림이 필요하다. 따라서 본고에서 필자는, 첫째, 외부 세계 현존 문제를 위한 흄의 논증 기저에 놓인 근본적 사유틀을 압축해서 드러낸다. 둘째, 이러한 사유틀을 기초로 (...) 해서 발현된 흄의 논증에 깃든 다양한 문제점들을 살핀다. 필자는 흄의 논증에 대한 비판을 면밀하게 수행하는 과정에서 김효명 교수가 『영국경험론』 제5장 말미(pp.152-162.)에서 흄의 견해를 줄곧 따라서 보인 해석이 직면하는 어려움도 보인다. 셋째, 지금까지 검토한 내용을 바탕으로, 결국 흄은 그의 자연주의를 지탱하는 능력에 일관되게 호소하면서 외부 세계 현존 문제에 대한 의미 있는 (즉, 존재론적 차원의 논의를 심리학적 차원의 논의로 전환하는) 답변을 제시하고자 하지만, 그의 노력은 그가 매우 의도성 짙게 ‘지각’과 ‘대상’을 상호 무분별히 뒤섞어서 쓰는 사정에 기인하기 때문에 논의에 일관성이 없으며, 이러한 비일관적 상황이 초래하는 결과는 그의 인간학에 대한 근원적 회의로 나타남이 지적될 것이다. (shrink)

McDowell has argued that external world scepticism is a pressing problem only in so far as we accept, on the basis of the argument from illusion, the claim that perceiving that p and hallucinating that p involve a highest common factor.

The external world sceptic tells some familiar narratives involving massive deception. Perhaps we are brains in vats. Perhaps we are the victim of a deceitful demon. You know the drill. The sceptic proceeds by observing first that victims of such deceptions know nothing about their external environment and that second, since we cannot rule out being a victim of such deceptions our- selves, our own external world beliefs fail to attain the status of knowledge. Discussions (...) of global external world scepticism tend to focus on the second step, where a number of well-known lines of resistance have been offered. But there has been little attention to the first, seemingly innocuous step. That will be the focus of this paper. Part one – sections 1, 2, and 3 – will explain why these standard narratives are not convincing examples of cases where there is no knowledge of the external world. In part two – section 4 – we shall undertake a useful case study. David Lewis’s ‘Elusive Knowledge’ is often thought of as presenting an epistemological vision that is somewhat friendly to external world scepticism: as Lewis himself presents things, there are contexts where external world knowledge ascriptions are uniformly false, and where true knowledge ascriptions are limited to either axiomatic truths or truths about our inner life. We examine his discussion in the light of the preceding reflections and show that the framework he presents is not so concessionary to global external world scepticism after all. (shrink)

I focus on a key argument for global external world scepticism resting on the underdetermination thesis: the argument according to which we cannot know any proposition about our physical environment because sense evidence for it equally justifies some sceptical alternative (e.g. the Cartesian demon conjecture). I contend that the underdetermination argument can go through only if the controversial thesis that conceivability is per se a source of evidence for metaphysical possibility is true. I also suggest a reason (...) to doubt that conceivability is per se a source of evidence for metaphysical possibility, and thus to doubt the underdetermination argument. (shrink)

This article explores the relationship between epistemic relativism and Pyrrhonian scepticism. It is argued that a fundamental argument for contemporary epistemic relativism derives from the Pyrrhonian problem of the criterion. Pyrrhonian scepticism is compared and contrasted with Cartesian scepticism about the external world and Humean scepticism about induction. Epistemic relativism is characterized as relativism due to the variation of epistemic norms, and is contrasted with other forms of cognitive relativism, such as truth relativism, conceptual (...) relativism and ontological relativism. An argument from the Pyrrhonian problem of the criterion to epistemic relativism is presented, and is contrasted with three other arguments for epistemic relativism. It is argued that the argument from the criterion is the most fundamental argument for epistemic relativism. Finally, it is noted how the argument of the present paper fits with the author’s previous suggestion that a particularist response to the Pyrrhonian sceptic may be combined with a naturalistic view of epistemic warrant to meet the challenge of epistemic relativism. (shrink)

Predictivism, the thesis that all things being equal a hypothesis that predicts a piece of evidence is better supported by that evidence than a hypothesis that only accommodates that evidence, comes in strong and weak forms. Interestingly, weak predictivism, which is widely accepted, can be used to formulate a persuasive argument against some forms of external world scepticism. In this article I formulate this predictivist argument and I explain why it deserves serious consideration despite the fact that (...) it only succeeds as a response to some forms of external world scepticism. (shrink)

According to an externalist theory of content the content of an individual’s thoughts and the meaning of her words need not supervene on her intrinsic history. Two individuals may be intrinsically exactly alike yet entertain different thoughts, and attach different meanings to the words they use. ETC, which has been most notably defended by Saul Kripke, Hilary Putnam and Tyler Burge, has attained the status of current orthodoxy. Nevertheless, some maintain that combining ETC with the premisses that we have privileged (...) access to our intentional states yields a surprising conclusion. It yields the conclusion that we can have a priori knowledge of features of the external world that seem only accessible to empirical investigation. Call the argument from ETC and privileged access to this conclusion the main argument. Some take the main argument to be a reductio of ETC. Since we have privileged access to our intentional states, and lack the a priori knowledge attributed by the main argument, ETC is false. Some take the main argument to refute the premisses that we have privileged access to those intentional states falling within the scope of ETC. Others see the main argument as a refutation of external world scepticism. We will show that the main argument does not support any of these interesting conclusions. We will show that the main argument does not threaten to restrict privileged access, refute external world scepticism, or constitute a reductio of ETC. More exactly, we will show that the most defensible version of ETC, even when combined with the premiss that we have unrestricted privileged access to our intentional states, yields no a priori knowledge of the external world. (shrink)

The classical arguments for scepticism about the external world are defended, especially the symmetry argument: that there is no reason to prefer the realist hypothesis to, say, the deceitful demon hypothesis. This argument is defended against the various standard objections, such as that the demon hypothesis is only a bare possibility, does not lead to pragmatic success, lacks coherence or simplicity, is ad hoc or parasitic, makes impossible demands for certainty, or contravenes some basic standards for a (...) conceptual or linguistic scheme. Since the conclusion of the sceptical argument is not true, it is concluded that one can only escape the force of the argument through some large premise, such as an aptitude of the intellect for truth, if necessary divinely supported. (shrink)

Fumerton’s distinctive brand of metaepistemological scepticism is compared and contrasted with the related position outlined by Stroud. It is argued that there are at least three interesting points of contact between Fumerton and Stroud’s metaepistemology. The first point of contact is that both Fumerton and Stroud think that (1) externalist theories of justification permit a kind of non-inferential, perceptual justification for our beliefs about non-psychological reality, but it’s not sufficient for philosophical assurance. However, Fumerton claims, while Stroud denies, that (...) (2) direct acquaintance with facts is sufficient for philosophical assurance. And this is important because Stroud thinks that (3) we have direct perceptual access or acquaintance with facts about the external world, while Fumerton denies this. (shrink)

The irreducibility thesis of phenomenal consciousness can only succeed against the sceptical attack and avoid solipsism iff it can coherently establish the transition from subjective certainty to the objectivity of knowledge. The sceptical attack on the relationship between the phenomenal qualitative character of experience about the subjects own mental fact and the awareness of the qualitative properties of the phenomenal object can be avoided through establishing the immediacy of experience. The phenomenal realist become successful in establishing the subjective certainty about (...) the knowledge of phenomenal consciousness, however, has been failed in establishing objective certainty of knowledge, which leads to several epistemological problems (i.e., scepticism about the independent existence of external world, knowledge about the external reality and the existence of other mind; popularly known as the harder problem of consciousness) in philosophy of mind. In this paper, my objective is to reveal the undesirable consequences of representationalism. Representationalism is not an ideal option for responding to the sceptical attack against the other minds and the reality of the external world. It always leaves an open question for us about the relation between the representation of the object of experience and consciousness. Representationalistic theories of experience violates the principles of phenomenality by rejecting the immediacy of experience and has been committing the pragmatic contradiction by reducing the phenomenal properties to representational properties. The categorization of knowledge about phenomenality as inferential knowledge by representationalist leave no room for foundational knowledge about phenomenality. (shrink)

Scepticism has been one of the standard problems of epistemology in modern times. It takes various forms – the most general one being the thesis that knowledge is impossible; but equally prominent are such versions as the notorious doubt about the existence of an external world, inaugurated by Descartes'Meditations, or doubts about the existence of objective values. Philosophers who undertake to refute scepticism – still a very popular exercise – try to show that knowledge is possible (...) after all, or to prove the existence of an external world, and so on. Sceptics, generally speaking, are seen as radical doubters – philosophers who call into question assumptions that are usually taken for granted by ordinary people as well as by other philosophers. Those doubts have to be refuted by showing that they are in some way unjustified. (shrink)

Hegel's philosophy aims at responding to the questions raised by modern scepticism concerning the accessibility of the external world, of other minds, and of one's own mind. A key-role in Hegel's argumentative strategy against modern scepticism is played here by Hegel's theory of recognition. Recognition mediates the constitution of individual self-consciousness and intersubjectivity: self-knowledge is not logically independent of the awareness of other minds. At the same time, recognition institutes the possibility of objective reference to the (...) world. In this way, in Hegel the theory of recognition furnishes a unitary response to the threefold sceptical issue of the accessibility of the external world, of other minds, and of one's own mind. The reference to a common world of public objects is thus possible only thanks to the mediation of recognitive capacities that are naturally possessed and socially articulated, which make possible the triangulation between self, world and others. (shrink)

In this paper, I will clarify Jonathan Schaffer's; debasing scepticism, highlighting its logical structure. 1 In many current discussions of scepticism, its scope is limited to propositions about the external world which, if known at all, are known a posteriori. The standard sceptical set-up goes as follows. The sceptic specifies a sceptical hypothesis, or counterpossibility, that is incompatible with the external-world propositions that I claim to know. The hypothesis – e.g. that I am a (...) brain in a vat – is claimed by the sceptic to be within the realm of metaphysical possibility. The sceptical argument, in a nutshell, runs as follows. Choose some external-world proposition that I claim to know, say H = I have hands. By the principle that knowledge is closed under known entailment, if I know H, then I know ∼SK = I am not a handless brain in a vat. My evidence does not enable me to know ∼SK. Hence I …. (shrink)

Radical scepticism contends that our knowledge of the external world is impossible. Particularly, radical scepticism can be motivated by the closure principle. Several commentators have noted that a straightforward way to respond to such arguments is via externalist strategies, e.g., Goldman, Greco, Bergmann. However, these externalist strategies are not effective against a slightly weaker form of the argument, a closure principle for rationally grounded knowledge, closureRK.\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${closure}_{RK.}$$\end{document} The sceptical (...) argument, framed around the closureRK\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {closure}_{\mathrm{RK}}$$\end{document} principle, targets rationally grounded knowledge. Although externalist strategies are ineffective against this form of argument, its conclusion can nonetheless be resisted by combining, in a novel way, the resources of Wittgenstein and Davidson. In particular, I argue that the sceptic is assuming an unrestricted way of using the closureRK\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {closure}_{\mathrm{RK}}$$\end{document} principle, which is incorrect. Alternatively, I argue for The Conditionality of Rational Support Thesis, i.e., the thesis that rational support via competent deduction is conditional. In particular, rational support must be provided within an evaluative system in which hinge propositions are presupposed and contentful beliefs are being evaluated. In the end, we can resist the closureRK\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {closure}_{\mathrm{RK }}$$\end{document}-based sceptical argument while retaining the closureRK\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {closure}_{\mathrm{RK}}$$\end{document} principle. (shrink)

According to veridicalism, your beliefs about the existence of ordinary objects are typically true, and can constitute knowledge, even if you are in some global sceptical scenario. Even if you are a victim of Descartes’ demon, you can still know that there are tables, for example. Accordingly, even if you don’t know whether you are in some such scenario, you still know that there are tables. This refutes the standard sceptical argument. But does it solve the sceptical problem posed by (...) that argument? I argue that it does not, because we do not know substantively more about the external world according to veridicalism than we do according to the sceptical argument. Rather, veridicalism merely reformulates what little knowledge we have. I then draw some general conclusions about the nature of the sceptical problem, the formulation of the standard argument, and the significance of this for some other, non-veridicalist strategies. (shrink)

According to radical scepticism, knowledge of the external world is impossible. Transcendental arguments are supposed to be anti-sceptical, but can they provide a satisfying response to radical scepticism? Especially, when radical scepticism is cast as posing a how-possible question, there is a concern that transcendental arguments are neither sufficient nor necessary for answering such question. In light of this worry, I argue that we can take a modest transcendental argument as a stepping stone for a (...) diagnostic anti-sceptical proposal, and I use a Wittgensteinian modest transcendental argument to illustrate my point. (shrink)

PYRRHONIAN SCEPTICISM, as presented in the writings of Sextus Empiricus, differs in various ways from the forms of scepticism that continue to be of such central concern to modern philosophers. Two differences stand out immediately. One is Pyrrhonism's practical orientation. For Sextus, scepticism is a way of life in which suspension of judgment leads to the peace of mind the sceptic identifies with happiness. The other is the puzzling failure on the part of the Pyrrhonists, along with (...) all other ancient sceptics, to formulate the sceptical problem that many modern and contemporary philosophers regard as fundamental and paradigmatic: the problem of our knowledge of the external world. (shrink)

A number of recent philosophers, including Michael Williams, Barry Stroud and Donald Davidson, have argued that scepticism about the external world stems from the founda‐tionalist assumption that sensory experience supplies the data for our beliefs about the world. In order to assess this thesis, I offer a brief characterisation of the logical form of sceptical arguments. I suggest that sceptical arguments rely on the idea that many of our beliefs about the world are‘underdetermined’by the evidence (...) on which they are based. Drawing on this characterisation of scepticism, I argue that Williams, Stroud and Davidson are right to see the foundationalist assumption as essential to the sceptic's argument, but wrong to think that scepticism is inevitable once that assumption is in place. By pursuing an analogy with some recent debates in the philosophy of science, I try to locate the additional assumptions which the sceptic must make, in order to derive her conclusion. (shrink)

This paper aims to motivate a scepticism about scepticism in contemporary epistemology. I present the sceptic with a dilemma: On one parsing of the BIV (brain-in-a-vat) scenario, the second premise in a closure-based sceptical argument will turn out false, because the scenario is refutable; on another parsing, the scenario collapses into incoherence, because the sceptic cannot even save the appearances. I discuss three different ways of cashing out the BIV scenario: ‘Recent Envatment’ (RE), ‘Lifelong Envatment’ (LE) and ‘Nothing (...) But Envatment’ (NBE). I show that RE scenarios are a kind of ‘local’ sceptical scenario that does not pose a significant threat to the possibility of perceptual knowledge as such. I then go on to consider the more radical (or global) LE and NBE scenarios, which do undermine the possibility of perceptual knowledge of an ‘external’ world by positing that it is conceivable that one has always been envatted and, hence, trapped in a ‘global’ illusion. I start by assuming that we could be in such a scenario (LE or NBE) and then spell out what we would need to presuppose for such scenarios to be capable of being actual. Drawing on some central insights from Wittgenstein’s anti-private language considerations, I show that the truth of a global scepticism would presuppose the possibility of a private ‘vat-language’, a notion that cannot be rendered coherent. But, if so, then neither can the sceptical scenarios that presuppose such a conception. (shrink)

In a recent article Dylan Dodd has argued that anyone who holds that all knowledge is evidence must concede that we know next to nothing about die external world. The argument is intended to show that any infallibilist account of knowledge is committed to scepticism, and that anyone who identifies our evidence with the propositions we know is committed to infallibilism. I shall offer some reasons for thinking Dodd's argument is unsound, and explain where his argument goes (...) wrong. (shrink)

A number of recent philosophers, including Michael Williams, Barry Stroud and Donald Davidson, have argued that scepticism about the external world stems from the foundationalist assumption that sensory experience supplies the data for our beliefs about the world. In order to assess this thesis, I offer abrief characterisation of the logical form of sceptical arguments. I suggest that sceptical arguments rely on the idea that many of our beliefs about the world are ‘underdetermined’ by the (...) evidence on which they are based. Drawing on this characterisation of scepticism, I argue that Williams, Stroud andDavidson are right to see the foundationalist assumption as essential to the sceptic’s argument, but wrong to think that scepticism is inevitable once that assumption is in place. By pursuing an analogy with some recent debates in the philosophy of science, I try to locate the additional assumptions which the sceptic must make, in order to derive her conclusion. (shrink)

I aim to provide a satisfying response to radical scepticism, a view according to which our knowledge of the external world is impossible. In the first chapter I investigate into the nature and the source of scepticism. Radical scepticism is motivated both by the closureRK-based and the underdeterminationRK-based sceptical arguments. Because these two sceptical arguments are logically independent, any satisfying anti-sceptical proposal must take both of them into consideration. Also, scepticism is a paradox, albeit (...) a spurious one, so we need to provide a diagnosis as to why we are lead into the paradox and why the alleged paradox misrepresents our epistemic standings. Hence, I advocate an obstacle-dissolving strategy for combating the sceptical problem. In chapter two, I discuss the anti-sceptical import of transcendental arguments. Although ambitious transcendental arguments are vulnerable to Stroud’s dilemma, I argue that modest transcendental arguments are promising. Modest transcendental arguments start from an undoubted psychological fact and then reveal some necessary theoretical commitments that we must make. Regarding these commitments, I submit that we are type II epistemically justified in believing them. Our commitments are type II justified in the sense that making these commitments can promote our epistemic goals, namely, the attainment of true beliefs and the avoidance of false beliefs. After that, in light of Cassam’s objection to transcendental arguments, I contend that a modest transcendental argument should be used as a stepping stone for a diagnostic anti-sceptical proposal. In chapter three, I develop a Davidsonian response to closureRK-based radical scepticism. This form of sceptical argument rests on the idea that there is no limitation on our acquisition of rationally grounded knowledge. I discuss Davidson’s theory of radical interpretation, the principle of charity and triangulation. Crucially, he argues that the content of a knowledge-apt everyday belief is determined by its typical cause and other relevant beliefs. Further, among different propositional attitudes, belief is prior to doubt. What follows is that doubt must be local because it must presume other content-determining beliefs. Also, I explore Davidson’s view on the concept of belief. On his view, in order to have a knowledge-apt belief, we must have the concept of knowledge-apt belief. We can command this concept by having the concept of objective truth. Objective truth requires that we are aware of and are capable of appreciating the possibility of a belief’s being true or false. And this possibility cannot be appreciated unless we have some related contentful beliefs to identify the content of the very belief. However, we are committed to, as opposed to believing, the proposition that the sceptical hypothesis does not obtain. It is impossible to appreciate the possibility of our fundamental commitments being false from our own perspective, because fundamental commitments specify the general cause of our beliefs. A change in this regard would cause a total change of the content of all beliefs, which leaves us no contentful belief at all to make this possibility intelligible. Therefore, the closureRK principle is not applicable to the evaluation of the sceptical hypothesis. Hence, we can retain the closureRK principle while evading the closureRK-based sceptical challenge. Unfortunately, the Davidsonian response cannot deal with the underdeterminationRK-based sceptical challenge, because we are not shown whether our rational support in the good case favours one’s everyday belief over its sceptical counterpart. In chapter four, I examine how epistemological disjunctivism can deal with underdeterminationRK-based radical scepticism. This form of sceptical argument assumes that our rational support provides at best inconclusive support for our beliefs. Therefore, a belief’s being rationally supported, no matter in the good case or in the bad case, is compatible with the belief’s being false. Epistemological disjunctivism claims that in paradigm cases of perceptual knowledge, our rational support can be both factive and reflectively accessible. The factive rational support at issue is one’s propositional seeing. I discuss both McDowell’s and Pritchard’s proposals for motivating factive seeing, and I argue for epistemological disjunctivism against three prime facie objections, i.e., the distinguishability problem, the basis problem and the access problem. When epistemological disjunctivism is shown to be a plausible view, I argue that underdeterminationRK-based radical scepticism can be dismissed. In particular, in the optimal case, factive rational support favours our everyday belief over the sceptical hypothesis. However, regarding closureRK-based radical scepticism, epistemological disjunctivism seems to licence a robust answer. The ambitious answer is that, in the good case, we can after all know the denial of the sceptical hypothesis in virtue of possessing factive rational support. And it is the immodesty of this answer that renders this response unpalatable. In the last chapter, I propose a combined treatment of the sceptical problem. Although both the Davidsonian response and the epistemological disjunctivist response can only deal with one aspect of the sceptical problem, their views are in fact mutually supportive. On the one hand, the Davidsonian response, together with a Wittgensteinian insight, shows that why rational support can only be provided in a local manner; on the other hand, epistemological disjunctivism reminds us that rational support can be factive in the good case. Putting these two points together allows us to answer the whole sceptical challenge in a uniform way. This combined proposal has three claims. First, our rational support can be both local and factive, so we can dismiss both sceptical arguments in one go. Second, the sceptical problem is a spurious paradox, so the combined treatment involves a diagnosis. This diagnosis starts from a modest transcendental argument which reveals some necessary commitments that we must make, and then proceeds to expose faulty assumptions in the sceptical paradox. Third, once the dubious assumptions are dislodged, we can evade the sceptical problem once and for all. In the end, we are offered with a satisfying response to radical scepticism. (shrink)

Wittgenstein is arguably the greatest philosopher of the last hundred years and scepticism is one of the central problems that modern philosophy faces. This collection is the first to be devoted to an examination of how that great philosopher's work bears on this fundamental philosophical problem. Wittgenstein's reaction to scepticism is complex, articulating both a sense that sceptical problems are ultimately unreal and a sense that scepticism teaches us something about the fundamental character of the human predicament. (...) The essays, specially written for this collection by distinguished philosophers and commentators on Wittgenstein, explore that reaction, addressing, in particular, scepticism about the existence of the external world and of other minds. In doing so, it explores issues not only in theory of knowledge but also in metaphysics, the philosophy of mind, language, perception and literature, as well as raising questions about the nature of philosophy itself. Several of the papers address the work of Stanley Cavell, perhaps the most influential commentator on the work of Wittgenstein, and Cavell replies in the final pieces to four of those papers. This collection is essential reading for students and scholars of Wittgenstein and anyone interested in the debate surrounding scepticism. (shrink)

The main problem of this study is David Hume’s (1711-76) view on Metaphysical Realism (there are mind-independent, external, and continuous entities). This specific problem is part of two more general questions in Hume scholarship: his attitude to scepticism and the relation between naturalism and skepticism in his thinking. A novel interpretation of these problems is defended in this work. The chief thesis is that Hume is both a sceptic and a Metaphysical Realist. His philosophical attitude is to suspend (...) his judgment on Metaphysical Realism, whereas as a common man he firmly believes in the existence of mind-independent, external, and continuous entities. Therefore Hume does not have any one position; accordingly, a form of “no one Hume” interpretation (Richard Popkin, Robert J. Fogelin, Donald L.M. Baxter) is argued for in the book. The key point in this distinction is the temporal difference between Hume’s philosophical and everyday views. It is introduced in order to avoid attributing a conscious contradiction to him (a problem which has not attracted enough attention in the literature). The method of the work is modelled on Peter Millican’s work on Hume and induction. The approach to the main problem is to study the two “profound” arguments against the senses that Hume presents in the Section 12 of An Enquiry concerning Human Understanding (1748). These arguments are first reconstructed in detail resulting in Millican-type diagrams of them and then Hume’s endorsement of them is established on the basis of the diagrams. The first profound argument concludes that Metaphysical Realism and thus any Realistic theory of perception is unjustified as well as the existence of God and the soul. The second argument goes further having first conceptual conclusion: the very notions of Real entitity, material substance, and bodies are completely out of the reach of the faculty of understanding. Therefore they ought to be rejected according to Hume. This is a consequence of the consistent use of the Humean faculty of reason: idea-analysis and inductive inference. The second profound argument thus concludes that believing in Metaphysical Realism is inconsistent with the rational attitude that is to refrain from this belief. Hence, if we attributed both of them to Hume, we would end up with a great philosopher who embraces a manifest contradiction. The study is finished by arguing that this sceptical and Metaphysically Realistic interpretation concurs well with (1) Hume’s professed Academical philosophy and (2) project of the science of human nature. (1) According to Hume, Academical philosophy is in the first place diffidence, modesty, and uncertainty including suspension on certain issues. Secondly, it is restriction of the range of topics for which experience can provide a standard of truth. This kind of empiricist epistemological realism is coherent with the sceptical attitude on Metaphysical Realism because the latter does not rule out inter-subjective consensus on what we experience. (2) Suspension of judgment on Metaphysical Realism coheres with the mind-dependency of the objects of Hume’s science of human nature: the understanding, passions, morals, aesthetics, politics, and the human culture in all of its manifestations. Although the study takes the first Enquiry to be Hume’s authorised word on the understanding, his juvenile work A Treatise of Human Nature (1739-40) is argued to support this “no one Hume” interpretation. Hume’s other works are also discussed when needed. (shrink)

John McDowell has recently changed his line of response to philosophical scepticism about the external world. He now claims to be in a position to use the strategy of transcendental argumentation in order to show the falsity of the sceptic’s misrepresentation of our ordinary epistemic standpoint. Since this transcendental argument begins from a weak and widely shared assumption shared with the sceptic herself the falsity of external world scepticism is now demonstrable even to her. (...) Building on the account of perceptual intentionality defended in the Woodbridge lectures, McDowell argues that the idea of narrow perceptual content is unavailable to anyone, including the sceptic. This argument is assessed by drawing out an analogy with parallel responses to error theories in ethics. (shrink)

In this article, a novel interpretation of one of the problems of Hume scholarship is defended: his view of Metaphysical Realism or the belief in an external world (that there are ontologically and causally perception-independent, absolutely external and continued, i.e. Real entities). According to this interpretation, Hume's attitude in the domain of philosophy should be distinguished from his view in the domain of everyday life: Hume the philosopher suspends his judgement on Realism, whereas Hume the common man (...) firmly believes in the existence of Real entities. The defended reading is thus a sceptical and Realist interpretation of Hume. As such, it belongs to the class of what can be called no-single-Hume interpretations (Richard H. Popkin, Robert J. Fogelin, Donald L. M. Baxter), by contrast to single-Hume readings, which include Realist (naturalist, New Humean) and the traditional Reid-Green interpretation (i.e. Hume believes that there are no Real entities). Hume's distinction between the domains of philosophy and everyday life, which is argued to be epistemological, is employed in order to reconcile his scepticism with his naturalism and constructive science of human nature. The article pays special attention to the too much neglected second profound argument against the senses in Part 1, Section 12 of Hume's first Enquiry and the corresponding argument in Section 4, Part 4, Book 1 of the Treatise. (shrink)

Jessica Wilson has recently offered a more sophisticated version of the self-defeat objection to Cartesian scepicism. She argues that the assertion of Cartesian scepticism results in an unstable vicious regress. The way out of the regress is to not engage with the Cartesian sceptic at all, to stop the regress before it starts, at the warranted assertion that the external world exists. We offer three reasons why this objection fails: first, the sceptic need not accept Wilson’s characterization (...) of the sceptical thesis and thus need not start her regress; second, even if she did commit to the regress, it would not undermine scepticism in the way Wilson envisages; and third, the appeal to mental state scepticism which is necessary to generate the second and subsequent steps in the regress is not justified. (shrink)

On the assumption that we may learn from our elders and betters, this paper approaches some fundamental questions in perceptual epistemology through a dispute between McDowell and Wright about external world scepticism.

In this paper, I would like to present G.E. Moore’s view on Scepticism and certainty with reference to his papers “Defence of common sense” “Proof of an external world” and “Certainty”. In section I following Moore’s “Proof of an External World” the distinction between empirical objects like paper, human hand, shoes and socks and private objects like images in dreams, double images, after images, and toothache have been highlighted. It has been pointed out that according (...) to Moore, no example of private objects in place of “these are my two hands” could have successfully refuted scepticism; and that Moore does follow Kant’s definition of external objects in order to prove the existence of the external world. The second section emphasizes two points; i) the example of these are my two hands is not a frivolous activity and ii) Moore does recognize the point of Descartes’ dream argument at least to the extent that de does recognize that knowing that P is different from Proving that P. In section III Moore’s attribution of certainty to empirical propositions has been highlighted by responding to the remarks made by Wittgenstein and Malcolm against Moore. In Section IV following Moore’s certainty, a logical explanation of Moore’s thesis that contingent propositions can be certain has been carried out. In addition to that an explanation of how Moore has weakened the dream argument by finding it incoherent. Finally, it has been concluded that Moore’s refutation of scepticism is quite successful in so far as scepticism has no place in common sense. (shrink)

The epistemological problem of the external world asks: (1) “How is knowledge of the external world possible given certain obstacles which make it look impossible?” This is a “how-possible?” question: it asks how something is possible given certain obstacles which make it look impossible (cf. Cassam 2007; Nozick 1981; Stroud 1984). Now consider the following question, which asks: (2) “How is a philosophically satisfying answer to (1) possible?” Skepticism is the thesis that knowledge of the (...) class='Hi'>external world is impossible. It therefore represents a negative answer to the first question. Meta-epistemological skepticism is the thesis that a satisfying philosophical explanation of how our knowledge of the external world is possible is itself impossible. It therefore represents a negative answer to the second question. In this thesis, I explore the prospects of meta-epistemological skepticism. In particular, I structure the thesis around two master arguments from for meta-epistemological skepticism. The first argument is that skepticism represents a kind of paradox which requires dispensing with a plausible principle or belief, or even 'platitude', which means that there's no philosophically satisfying response to the paradox (see, e.g., Stroud 1984), and the second argument is “Stroud’s dilemma” (cf. Cassam 2009), that either we explain how external world knowledge is possible by reference to what external world knowledge we have, thereby failing to answer the philosophical question adequately, or else we don't, but then we succumb to first-order skepticism. I argue that the first argument fails to provide adequate support for meta-epistemological skepticism. However, the second argument, Stroud’s dilemma, is plausible and withstands serious objections (e.g., from Sosa 1994, Williams 1996, and Cassam 2009). In short, while the worry emerging out of the 'skeptical paradox' view fails to adequately support meta-epistemological skepticism, Stroud’s dilemma succeeds. Fortunately, it doesn't show that we lack external world knowledge; we rather just can't explain, philosophically, how it's possible. We may have first-order knowledge without understanding how it's possible. This thesis therefore represents a partial defense of meta-epistemological skepticism. Meta-epistemological skepticism is a live option in epistemology. (shrink)