Relevant Alternative Replies to Skepticism

The most prominent arguments for scepticism in modern epistemology employ closure principles of some kind. To begin my discussion of such arguments, consider Simple Knowledge Closure (SKC): (SKC) (Kxt[p] ∧ (p → q)) → Kxt[q].1 Assuming its truth for the time being, the sceptic can use (SKC) to reason from the two assumptions that, firstly, we don’t know ¬sh and that, secondly, op entails ¬sh to the conclusion that we don’t know op, where ‘op’ and ‘sh’ are shorthand for ‘ordinary (...) proposition’ and ‘sceptical hypothesis’ respectively. (SKC), however, fails for familiar reasons: since knowledge entails belief (KB), we can derive the falsity (F) from (SKC) by hypothetical syllogism, and thus reduce (SKC) to absurdity: (KB) Kxt[p] → Bxt[p]. (F) (Kxt[p] ∧ (p → q)) → Bxt[q]. (shrink)

The phenomenon of knowledge is a fundamental issue in epistemology as a main branch of philosophy concerned with knowledge related problems. Over time, epistemologists attempted to give us or provide clues as to what reality actually is, that is the question of the certainty of knowledge has always been topical in any epistemic enterprise. The search for knowledge becomes more cumbersome when one considers the challenge of the skeptics and sophists about the ability of man knowing anything for certain. To (...) some philosophers, the emergence of the skeptics’ challenge is seen as an attempt to bring this noble enterprise into a quagmire. However, the introduction of Descartes foundationalism opens a new chapter and a serious challenge to the skeptics' position on the certainty of knowledge. Consequently, many have asked the question: is Descartes foundationalism merely an answer to the skeptic's challenge or a way forward for epistemology? This paper examines this question with a view to asserting a position regarding the issue, which is that it is both a response and a way forward for epistemology. (shrink)

In this comment, we will focus on Greco’s brief for agent reliabilism in preference to simple reliabilism. Agent reliabilism differs from simple reliabilism primarily in requiring, not merely belief that results from a reliable process, but belief grounded in stable dispositions that make up the subject’s character.

But it’s not the mere fact that the RA theorist needs an account of ‘ruling out’ and ‘relevance’ that has tended to lead people to regard the RA approach with suspicion. In itself, this simply means that the RA theorist has some further work to do; and what theorist doesn’t? No; the principal source of scepticism regarding the ability of the RA theorist to come up with a complete and satisfactory account of knowing stems, rather, from an unhappiness with the (...) specific elaborations of the core RA claim that various theorists have offered; for these elaborations have typically involved some rather controversial claims and/or assumptions, and it is against these claims/assumptions that the bulk of the criticism of the whole RA approach has been directed. (shrink)

The paper takes as its starting point the observation that people can be led to retract knowledge claims when presented with previously ignored error possibilities, but offers a noncontextualist explanation of the data. Fallibilist epistemologies are committed to the existence of two kinds of Kp -falsifying contingencies: (i) Non-Ignorable contingencies [NI-contingencies] and (ii) Properly-Ignorable contingencies [PI-contingencies]. For S to know that p, S must be in an epistemic position to rule out all NI-contingencies, but she need not be able to (...) rule out the PI-contingencies. What is required vis-à-vis PI-contingencies is that they all be false . In mentioning PI-contingencies, an interlocutor can lead S mistakenly to think that these contingencies are NI-contingencies, when in fact they are not. Since S cannot rule out these newly mentioned contingencies and since she mistakenly takes them to be NI-contingencies , it is quite natural that she retract her earlier knowledge claim. In short, mentioning NI-contingencies creates a distortion effect. It makes S think that the standards for knowledge are higher than they actually are, which in turn explains why she mistakenly thinks she lacks knowledge. Conclusion: The primary linguistic data offered in support of contextualism can be explained without resorting to contextualism. (shrink)

In this paper we survey some main arguments for and against epistemological contextualism. We distinguish and discuss various kinds of contextualism, such as attributer contextualism (the most influential version of which is semantic, conversational, or radical contextualism); indexicalism; proto-contextualism; Wittgensteinian contextualism; subject, inferential, or issue contextualism; epistemic contextualism; and virtue contextualism. Starting with a sketch of Dretske's Relevant Alternatives Theory and Nozick's Tracking Account of Knowledge, we reconstruct the history of various forms of contextualism and the ways contextualists try to (...) handle some notorious epistemological quandaries, especially skepticism and the lottery paradox. Then we outline the most important problems that contextualist theories face, and give overviews of their criticisms and defenses as developed in this issue. (shrink)

According to the relevant alternatives theory of knowledge (RA), I know that p only if my evidence eliminates all relevant alternatives to p . Jonathan Schaffer has recently argued that David Lewis's version of RA, which is perhaps the most detailed version yet provided, cannot account for our failure to know in cases involving missed clues, that is, cases in which we see but fail to appreciate decisive evidence. I argue, however, that Lewis's version of RA survives exposure to missed (...) clue cases. Moreover, even though Schaffer maintains that Lewis's Rule of Belief provides no protection against missed clue cases, I argue that we should credit the Rule of Belief with ensuring the survival of Lewis's version of RA. (shrink)

In “Contextualism and Knowledge Attributions,” I argue that advocates of the “Relevant Alternatives” theory of knowledge fall into certain mistakes result if they tie the content of a knowledge attribution, on a given occasion of use, too tightly to what the range of relevant alternatives is on that occasion, and I sketch an alternative approach to the issues involved that avoids such mistakes. In “The Shifting Content of Knowledge Attributions,” Anthony Brueckner charges that my own account of these matters falls (...) to an objection of his. But Brueckner is wrong about this, as I’ll here argue. (shrink)

Although several important methodologies implicitly assume the truth of epistemic conservatism, the view that holding a belief confers some measure of justification on the belief, recent criticisms have led some to conclude that epistemic conservatism is an implausible view. That conclusion is mistaken. In this article, I propose a new formulation of epistemic conservatism that is not susceptible to the criticisms leveled at earlier formulations of epistemic conservatism. In addition to withstanding these criticisms, this formulation of epistemic conservatism has several (...) benefits. First, this formulation has the benefits of earlier formulations of epistemic conservatism, that is to say it makes sense of our intuitions about justification in regard to both memory beliefs and beliefs for which we have forgotten our evidence. Second, it provides a good way of responding to the skeptic’s challenge concerning the possibility of possessing knowledge of the external world posed by the Alternative Hypotheses argument. Third, it provides responses to both forms of a new skeptical problem plaguing basic knowledge structure theories, the Problem of Easy Knowledge formulated by Stewart Cohen. I argue that given the many benefits of this formulation of epistemic conservatism and the fact that it is not vulnerable to the criticisms that undermine earlier formulations of epistemic conservatism, this formulation of epistemic conservatism is a plausible view to maintain. (shrink)

Contextualists claim two important virtues for their view. First, contextualism is a non-skeptical epistemology, given the plausible idea that not all contexts invoke the high standards for knowledge needed to generate the skeptical conclusion that we know little or nothing. Second, contextualism is able to preserve closure concerning knowledge – the idea that knowledge is extendable on the basis of competent deduction from known premises. As long as one keeps the context fixed, it is plausible to think that some closure (...) principle can be articulated that will survive scrutiny. Opponents of contextualism often try to gain an advantage over it by claiming that their view mimics these virtues of contextualism as well as having other virtues. A recent example of the same is termed ‘contrastivism," as presented by Jonathan Schaffer. I will argue that the representation made is chimerical, that in fact contrastivism has no hope of mirroring these twin virtues of contextualism. (shrink)

L'analisi particolareggiata della morale cartesiana rileva il ruolo essenziale che la volontà riveste tanto nella morale provvisoria quanto nella cosiddetta morale definitiva o scientifica. Nella morale provvisoria l'influenza della volontà si rispecchia sulle due logiche opposte che vi convivono: quella pragmatica e quella intellettualista. Apparentemente, l'etica provvisoria ottiene di rendere compatibili le due logiche perché l'azione che momentaneamente è sufficiente a se stessa, nel futuro sarà subordinata alle verità teoriche scoperte; in realtà, è soltanto la volontà a far sì che (...) le due logiche siano possibili allo stesso tempo. (shrink)

Single-premise epistemic closure is the principle that: if one is in an evidential position to know that P where P entails Q, then one is in an evidential position to know that Q. In this paper, I defend the viability of opposition to closure. A key task for such an opponent is to precisely formulate a restricted closure principle that remains true to the motivations for abandoning unrestricted closure but does not endorse particularly egregious instances of closure violation. I focus (...) on two brands of epistemic theory that naturally incorporate closure restrictions. The first type holds that the truth value of a knowledge ascription is relative to a relevant question. The second holds that the truth value of a knowledge ascription is relative to a relevant topic. For each approach, I offer a formalization of a leading theory from the literature and use this formalization to evaluate the theory’s adequacy in terms of a precise set of desiderata. I conclude that neither theory succeeds in meeting these desiderata, casting doubt on the viability of the underlying approaches. Finally, I offer a novel variant of the topic-sensitive approach that fares better. (shrink)

I argue in this paper that philosophers have not clearly introduced the concept of a body in terms of which the problem of other minds and its solutions have been traditionally stated; that one can raise fatal objections to attempts to introduce this concept; and that the particular form of the problem of other minds which is stated in terms of the concept is confused and requires no solution. The concept of a "body" which may or may not be the (...) body of a person, which is required to state the traditional problem, is, on close examination, incoherent and cannot be introduced into a reasonable philosophical discussion. Also published in The Philosophy of the Body, Rejections of Cartesian Dualism, ed. Stuart F. Spicker. (shrink)

Externalist theories of knowledge often claim that whether a person's true belief is knowledge depends on the reliability of the faculties that produced the belief. Some philosophers think that the force of Cartesian skeptical arguments presents a problem for these theories. Externalism seems to entail a too-easy response to skepticism: since whether we know depends mainly on the reliability of our faculties, and skeptical arguments give us no reason to think our faculties unreliable, such arguments do not threaten our knowledge. (...) Many have thought that the ease with which Externalists respond to skepticism should prompt us to reject their view. ;In my dissertation, I attempt to answer this objection by providing Externalists with a more plausible response to skepticism. My response borrows from Relevant Alternatives theories, which tell us when we have to be able to rule out alternatives to our beliefs in order for those beliefs to amount to knowledge. Such theories typically argue that far-fetched alternatives raised by the skeptic are not relevant, so our inability to rule them out does not deprive us of knowledge. RA theories have attracted attention recently for their purported success in responding to skepticism. I believe that two prominent RA theories should in fact be rejected, but that some RA insights should be adopted by Externalists. ;To show this, I first clarify what RA theories are, and spell out their differences. I then argue against two prominent RA theories. Against one, I defend the closure principle---the principle according to which knowledge is closed under known entailment. Against the other , I argue that we need not postulate that 'know' is a contextual term in order to explain the power of skeptical arguments. I then develop my own RA theory, which claims that when we encounter skeptical arguments, we often cease to believe propositions that we would otherwise know. I show how this theory can account for the power of skeptical arguments, and can helpfully be appended to Externalist theories of knowledge, to give them a more plausible response to skepticism. (shrink)

In Meanings, Manners, and Scepticism, I argue that the ordinary language philosopher, the relevant alternativist, and the contextualist fail to refute the sceptic. I argue that they fail to refute the sceptic because their arguments critically rest on a number of both dogmatic and erroneous assumptions. In particular they rest on the dogmatic and erroneous assumptions that common sense is threatened by skepticism, that ordinary linguistic behaviour is of epistemic significance, and that the sceptic's departure from the linguistic norm suffices (...) to prove his sceptical alternatives irrelevant to the truth of ordinary claims to know. I argue that the first assumption is mistaken because it wrongly assumes that common sense consists not only of first-order beliefs about the world, but also second-order knowledge beliefs about those beliefs. I argue that the second assumption is mistaken because it conflates two logically distinct sets of standards: the standards of appropriate and the standards of true assertion. Finally, I argue that the third assumption is mistaken because it rests on a confusion of the kind of standard operative in ordinary knowledge-discourse with the kind of standard the sceptic appeals to when he reasons that we can never know. I conclude that appealing to ordinary linguistic behaviour and habits cannot suffice to prove the sceptic's hypothesis irrelevant to the truth of our knowledge claims, though insofar as common sense does not include second-order knowledge beliefs the truth of even the most radical skepticism cannot threaten our ordinary claims to know. (shrink)

Skepticism remains a central and defining issue in epistemology, and in the wider tradition of Western philosophy. To better understand the contemporary position of this important philosophical subject, Allan Hazlett introduces a range of topics, including: -/- • Ancient skepticism • skeptical arguments in the work of Hume and Descartes • Cartesian skepticism in contemporary epistemology • anti-skeptical strategies, including Mooreanism, nonclosure, and contextualism • additional varieties of skepticism • the practical consequences of Cartesian skepticism -/- Presenting a comprehensive survey (...) of the key problems, arguments, and theories, together with additional readings, A Critical Introduction to Skepticism is an ideal guide for students and scholars looking to understand how skepticism is shaping epistemology today. (shrink)

The main argument given for relevant alternatives theories of knowledge has been that they answer scepticism about the external world. I will argue that relevant alternatives also solve two other problems that have been much discussed in recent years, a) the bootstrapping problem and b) the apparent conflict between semantic externalism and armchair self-knowledge. Furthermore, I will argue that scepticism and Mooreanism can be embedded within the relevant alternatives framework.

Dretske's conclusive reasons account of knowledge is designed to explain how epistemic closure can fail when the evidence for a belief does not transmit to some of that belief's logical consequences. Critics of Dretske dispute the argument against closure while joining Dretske in writing off transmission. This paper shows that, in the most widely accepted system for counterfactual logic , conclusive reasons are governed by an informative, non-trivial, logical transmission principle. If r is a conclusive reason for believing p in (...) Dretske's sense, and if p logically implies q, and if p and q satisfy one additional condition, it follows that r is a conclusive reason for believing q. After introducing this additional condition, I explain its intuitive import and use the condition to shed new light on Dretske's response to scepticism, as well as on his distinction between the so-called ‘lightweight’ and ‘heavyweight’ implications of a piece of perceptual knowledge. (shrink)

A commonly expressed worry in the contemporary literature on the problem of epistemological scepticism is that there is something deeply intellectually unsatisfying about the dominant anti-sceptical theories. In this paper I outline the main approaches to scepticism and argue that they each fail to capture what is essential to the sceptical challenge because they fail to fully understand the role that the problem of epistemic luck plays in that challenge. I further argue that scepticism is best thought of not as (...) a quandary directed at our possession of knowledge simpliciter, but rather as concerned with a specific kind of knowledge that is epistemically desirable. On this view, the source of scepticism lies in a peculiarly epistemic form of angst. It is always by favour of Nature that one knows something. [Wittgenstein 1969: §505]. (shrink)

So, C. I don’t know that T. Premises 1 and 2 are both plausible. However, C seems false—I do seem to know that there is a tree before me. AI presents a puzzle because its two plausible premises yield a conclusion whose negation is plausible. And no matter whether we accept or reject AI, we find that we must give up something plausible—either premise 1, premise 2, or the negation of C. But which of these should we give up? I (...) call this question the skeptical puzzle.1 Recently, Mark Heller2 has argued that we can solve the skeptical puzzle by giving up premise 2. I argue, however, that Heller does not adequately respond to an objection to his proposed solution. I go on to argue that we can solve the skeptical puzzle by giving up premise 1. (shrink)

I offer a critical treatment of the contrastivist response to the problem of radical scepticism. In particular, I argue that if contrastivism is understood along externalist lines then it is unnecessary, while if it is understood along internalist lines then it is intellectually dissatisfying. Moreover, I claim that a closer examination of the conditions under which it is appropriate to claim knowledge reveals that we can accommodate many of the intuitions appealed to by contrastivists without having to opt for this (...) particular brand of epistemological revisionism. (shrink)

There’s something deeply right in the idea that knowledge requires an ability to discriminate truth from falsity. Failing to incorporate some version of the discrimination requirement into one’s epistemology generates cases of putative knowledge that are at best problematic. On the other hand, many theories that include a discrimination requirement thereby appear to entail violations of closure. This prima facie tension is resolved nicely in Jonathan Schaffer’s contrastivism, which I describe herein. The contrastivist take on relevant alternatives is implausible, however, (...) and this then threatens to undermine contrastivism’s anti-skeptical results. (shrink)

A variant of Hilary Putnam's model-theoretic argument against metaphysical realism appears to show that our quantifiers do not determinately range over absolutely everything. This paper argues that some recent attempts to respond to the quantificational skeptic are unsuccessful and offers an alternative response: the key to answering the skeptic is not to refute her argument but to realize that the argument's setup prevents it from being convincing to those it is directed at.

The KK principle is typically rejected in externalist accounts of knowledge. However, a standard general argument for this rejection is in need of a supportive explication. In a recent paper, Samir Okasha argues that the standard externalist argument in question is fallacious. In this paper I start off with some critical discussion of Okasha’s analysis before suggesting an alternative way in which an externalist might successfully present such a case. I then further explore this issue via a look at how (...) Fred Dretske’s externalist epistemology, one of the exemplifying accounts, can explain failure of the KK principle. (shrink)

Empirical knowledge exists in the form of antiskeptical conditionals, which are propositions like [if I am not undetectably deceived, then I am holding a pen]. Such conditionals, despite their trivial appearance, have the same essential content as the categorical propositions that we usually discuss, and can serve the same functions in science and practical reasoning. This paper sketches out two versions of a general response to skepticism that employs these conditionals. The first says that our ordinary knowledge attributions can safely (...) be replaced by statements using antiskeptical conditionals, which provides a way around the standard sort of skeptical argument while accepting its soundness with respect to the usual targets. The second analyzes the objects of our ordinary knowledge attributions as antiskeptical conditionals, which allows us to refute, not just evade, the skeptic's argument. Both versions compare favorably to the best-knowncurrent approaches to skepticism, including semantic contextualism. (shrink)

Epistemic closure has been a central issue in epistemology over the last forty years. According to versions of the relevant alternatives and subjunctivist theories of knowledge, epistemic closure can fail: an agent who knows some propositions can fail to know a logical consequence of those propositions, even if the agent explicitly believes the consequence (having “competently deduced” it from the known propositions). In this sense, the claim that epistemic closure can fail must be distinguished from the fact that agents do (...) not always believe, let alone know, the consequences of what they know—a fact that raises the “problem of logical omniscience” that has been central in epistemic logic. This paper, part I of II, is a study of epistemic closure from the perspective of epistemic logic. First, I introduce models for epistemic logic, based on Lewis’s models for counterfactuals, that correspond closely to the pictures of the relevant alternatives and subjunctivist theories of knowledge in epistemology. Second, I give an exact characterization of the closure properties of knowledge according to these theories, as formalized. Finally, I consider the relation between closure and higher-order knowledge. The philosophical repercussions of these results and results from part II, which prompt a reassessment of the issue of closure in epistemology, are discussed further in companion papers. As a contribution to modal logic, this paper demonstrates an alternative approach to proving modal completeness theorems, without the standard canonical model construction. By “modal decomposition” I obtain completeness and other results for two non-normal modal logics with respect to new semantics. One of these logics, dubbed the logic of ranked relevant alternatives, appears not to have been previously identified in the modal logic literature. More broadly, the paper presents epistemology as a rich area for logical study. (shrink)

According to the Relevant Alternatives (RA) Theory of knowledge, knowing that something is the case involves ruling out (only) the relevant alternatives. The conception of knowledge in epistemic logic also involves the elimination of possibilities, but without an explicit distinction, among the possibilities consistent with an agent’s information, between those relevant possibilities that an agent must rule out in order to know and those remote, far-fetched or otherwise irrelevant possibilities. In this article, I propose formalizations of two versions of the (...) RA theory. Doing so clarifies a famous debate in epistemology, pitting Fred Dretske against David Lewis, about whether the RA theorist should accept the principle that knowledge is closed under known implication, familiar as the K axiom in epistemic logic. Dretske’s case against closure under known implication leads to a study of other closure principles, while Lewis’s defense of closure by appeal to the claimed context sensitivity of knowledge attributions leads to a study of the dynamics of context. Having followed the first lead at length in other work, here I focus more on the second, especially on logical issues associated with developing a dynamic epistemic logic of context change over models for the RA theory. (shrink)

Although Kripke’s skepticism leads to the conclusion that meaning does not exist, his argument relies upon the supposition that more than one interpretation of words is consistent with linguistic evidence. Relying solely on metaphors, he assumes that there is a multiplicity of possible interpretations without providing any strict proof. In his book The Taming of the True, Neil Tennant pointed out that there are serious obstacles to this thesis and concluded that the skeptic’s nonstandard interpretations are “will o’ wisps.” In (...) this paper, contra Tennant, I demonstrate how to construct alternative interpretations of the language of algebra. These constructed interpretations avoid Tennant’s objections and are shown to be interdefinable with the standard interpretation. Kripke’s skepticism is, as it were, an incarnate demon. In contrast, it is currently uncertain whether the same technique is generally applicable to the construction of an alternative interpretation of natural language. However, the reinterpretation of those aspects of natural language that directly relate to numbers seems to be a promising candidate for the development of nonstandard interpretations of natural language. (shrink)

Traditionally, skeptics as well as their opponents have agreed that in order to know that p one must be able, by some preferred means, to rule out all the alternatives to p. Recently, however, some philosophers have attempted to avert skepticism not (merely) by weakening the preferred means but rather by articulating a subset of the alternatives to p — the so-called relevant alternatives — and insisting that knowledge that p requires only that we be able (by the preferred means) (...) to rule out members of the set. In this paper I argue that a precise formulation of this new approach reveals it inadequate as a solution to skepticism. (shrink)

Skeptics try to persuade us of our ignorance with arguments like the following: 1. I don't know that I am not a handless brain-in-a-vat [BIV]. 2. If I don't know that I am not a handless BIV, then I don't know that I have hands. Therefore, 3. I don't know that I have hands. The BIV argument is valid, its premises are intuitively compelling, and yet, its conclusion strikes us as a absurd. Something has to go, but what? Contextualists contend (...) that an adequate solution to the skeptical problem must: (i) retain epistemic closure, (ii) explain the intuitive force of skeptical arguments by explaining why their premises initially seem so compelling, and (iii) account for the truth of our commonsense judgment that we do possess lots of ordinary knowledge. Contextualists maintain that the key to such a solution is recognizing that the semantic standards for 'knows' vary from context to context such that in skeptical contexts the skeptic's premises are true and so is her conclusion; but in ordinary contexts, her conclusion is false and so is her first premise. Despite its initial attractiveness, the contextualist solution comes at a significant cost, for contextualism has many counterintuitive results. After presenting the contextualist solution, I identify a number of these costs. I then offer a noncontextualist solution that meets the adequacy constraint identified above, while avoiding the costs associated with contextualism. Hence, one of the principal reasons offered for adopting a contextualist theory of knowledge -- its supposedly unique ability to adequately resolve the skeptical problem -- is undermined. (shrink)

There are powerful skeptical challenges to the idea that we are free. And yet, it seems simply impossible for us to shake the sense that we really are free. Some are convinced that the skeptical challenges are insurmountable and resign themselves to living under an illusion, while others argue that the challenges can be met. Even among those who believe that our sense of ourselves as free is at least roughly accurate, there are deep differences of opinion concerning what freedom (...) requires. On the one hand, there are “libertarians” about freedom, those who believe both that we are free and that freedom requires the falsity of determinism. On the other hand, there are “compatibilists”, those who believe that freedom is compatible with determinism. While there is an impressive variety of arguments and motivations available on all sides of the debate over freedom, our inescapable sense of ourselves as free has played a recurrent and key role in the debate, sometimes explicit and sometimes not. In this paper, I explore one way that our self-conception has been used by libertarians against compatibilists, and I argue that the reasoning employed is not convincing. The libertarian appeal to our self-conception hinges on locating in each of us an essential commitment to indeterminism, or, more cautiously, a commitment to something that, with the addition of a few plausible (if not self-evident) premises, entails indeterminism. The idea, then, is that we are “natural” indeterminists, seeing our actions as undetermined (or, again, more cautiously, as having qualities that, upon reflection, we can recognize entail the falsity of determinism). By itself, this is not an argument to the effect that we are correct in 1 believing that our actions are undetermined, or to the effect that freedom requires indeterminism. But if we are in fact natural indeterminists when it comes to our own actions, then that fact serves as important motivation for libertarianism, especially if our supposed natural indeterminism captures our unshakeable sense of freedom. Kant famously located our sense of freedom in our nature as rational agents, claiming that we must act under the “idea of freedom.”2 This has suggested to many that: (R) Rational deliberators, in virtue of their very nature as rational deliberators, must represent themselves as free.. (shrink)

Roughly characterized, solipsism is the skeptical thesis that there is no reason to think that anything exists other than oneself and one’s present experience. Since its inception in the reflections of Descartes, the thesis has taken three broad and sometimes overlapping forms: Internal World Solipsism that arises from an account of perception in terms of representations of an external world; Observed World Solipsism that arises from doubts as to the existence of what is not actually present sensuously in experience; Unreal (...) World Solipsism that arises from doubts as to the reality of the perceived world. This book attempts to give a rationally warranted refutation of all three forms. Over time, a vast number of putative rebuttals of solipsism have been proposed. The first half of the book clears the terrain for more productive investigation by showing in detail how each of these various responses fails. Among the simpler of such responses is the claim to have knowledge and certainty about everyday matters (Moore, Austin, Quinton, Pollock). Another is to appeal to pragmatic considerations dictated by the fact of one’s living in the world (Wittgenstein, Rescher, Ayer, Will, Strawson). Yet another is to undermine the skeptical thesis by applying it to itself (Plato, Hume, Russell, Johnson). All of these simpler approaches are found to be inadequate or irrelevant (Chapters 2 and 3). Other responses are more complex in that they presuppose certain basic positions with regard to the nature of cognition, meaning, language, or thought. Consequently, showing how they fail often involves showing the falsity of their underlying views. One such approach maintains that any empirical enquiry presupposes the existence of material objects (Neurath, Wittgenstein, Sellars, Quine, Gurwitsch, Williams, Rorty, BonJour), and that consequently solipsism is a problem peculiar to a mistaken foundationalist epistemology that purports to derive all warranted belief about the world from sensuous data. However, on examination, the various lines of reasoning advanced are found to be fallacious (Chapter 4). A closely-related approach is to claim that any empirical enquiry presupposes background truths, and that consequently solipsism is parasitic in the sense that it is based on truths that it purports to deny (Heidegger, Wittgenstein, Sellars, Quine). Such a self-contradictory situation is shown to obtain for only one form of solipsism, representational solipsism with its classical external world problem dating back to Descartes (Chapter 5). Another approach is to appeal to linguistic considerations in order to level charges of meaninglessness against solipsism (Wittgenstein, Austin, Ryle, Putnam, Clarke, Stroud). However, the charges are easily shown to be unwarranted (Chapter 6), a conclusion subsequently corroborated by a briefly sketched first-person account of meaning (Chapter 7). A further approach is to claim that all philosophical thinking must involve linguistic concepts, that language is intersubjective and tied to objects, and hence that solipsism is conceptually parasitic, and hence calls into question a conceptual scheme that it presupposes (Kant, Strawson, Wittgenstein, Sellars, Quine, Rorty). However, it may be shown that language is not incorrigibly wedded to objects, and in revised form it may be used to state solipsistic theses (Chapter 8). This conclusion is further supported by a refutation of various arguments against the possibility of private language (Wittgenstein, Sellars, Goodman, Rorty, Gadamer), as well as by the empirical evidence of everyday thinking that commonly takes place without reliance on the structures of public language (Chapter 9). The final chapters are more directly constructive. Following foundationalist procedure, a survey is undertaken of the sensuous data of first-person experience in its various modalities and their interrelationships (Chapter 10). An account is given of the bodily nature of the experiencing subject or self that feels, that wills, and that thinks, as well as of the spontaneity of the self or its capacity for free choice (Chapter 11). Rational warrant is then provided for thinking that items randomly perceived through a subject’s spontaneity or free will, continue to exist when unperceived, thus refuting forms of Observed World Solipsism that deny the existence of unperceived objects (Chapter 12). Finally, it is argued with regard to Unreal World Solipsism that while the scenarios it proposes cannot be dismissed as impossible, the absence of any supporting evidence whatever in their favor makes the espousal of any of them both arbitrary and an irrational leap (Chapter 13). (shrink)

This discussion surveys recent developments in the treatment of the epistemological problem of skepticism. These are arguments which attack our knowledge of certain truths rather than, say, our belief in the existence of certain entities. In particular, this article focuses on the radical versions of these skeptical arguments, arguments which purport to show that knowledge is, for the most part, impossible, rather than just that we lack knowledge in a particular discourse. Although most of the key recent developments in this (...) area have taken place since the late 1980s and early 1990s, it is necessary to also discuss some of the movements that have developed since 1970 in order to give these recent developments the necessary setting. The date of 1970 is dictated by the publication in that year of Fred Dretske’s seminal article “Epistemic Operators,” which both pushed a “relevant alternatives” theory of knowledge to the fore of discussion and also brought into focus one possible line of argument against the so-called “closure” principle for knowledge. In so doing, it provided one of the main sources of response to the emergent.. (shrink)