Moore’s proof consists of the inference of both “Two hands exist at this moment” and “At least two external objects exist at this moment” from the premise “Here is one hand and here is another.” The paper claims that the proof succeeds in refuting both idealism (“There are no external objects”) and skepticism (“Nobody knows that there are external objects”). The paper defends Moore’s proof against the following objections: Idealism does not deny that there (...) is an external world so Moore’s proof is beside the point; Moore may be mistaken about the premise; Moore has failed to prove the premise; Moore has failed to show how he knows the premise; the proof leads to an infinite regress; the proof begs the question because the premise assumes what needs to be proved; the premise depends upon a shaky inference; the premise rests upon evidence of the senses and thus begs the question; the proof fails to convince the skeptic. (shrink)

We develop a reading of Moore’s “Proof of an External World” that emphasizes the connections between this paper and Moore’s earlier concerns and strategies. Our reading has the benefit of explaining why the claims that Moore advances in “Proof of an External World” would have been of interest to him, and avoids attributing to him arguments that are either trivial or wildly unsuccessful. Part of the evidence for our view comes from unpublished drafts which, (...) we believe, contain important clues concerning Moore’s aims and intent. While our approach to PEW may be classified alongside other broadly "metaphysical" readings, we believe that a proper recognition of the continuity in Moore’s philosophical concerns and strategies across his philosophical career shows that the customary distinction between "epistemological" and "metaphysical" interpretative approaches to PEW is at best superficial. (shrink)

(2008). Neither Dogma nor Common sense: Moore's confidence in his ‘proof of an external world’1. British Journal for the History of Philosophy: Vol. 16, No. 1, pp. 163-195.

SummaryThere is an enormous literature on Moore's so‐called “proof”per se, but practically nothing has been written on the distinctions upon which the proof is bases, such as “being presented in space” and “being met with in space”. These are crucial to the argument, since Moore wishes to draw the line between the external and internal world via such distinctions. The author argues that these distinctions themselves crucially depend on a point that Moore does not argue for, (...) but assumes, namely that afterimages, negative after‐images, some sense‐data and pains are private to those that have them, and that two different people cannot sense numerically the same after‐images, pains etc. The author shows that this assumption is nonsense and that the entire proof, based upon it, therefore fails. (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.

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 common view about Moore’s Proof of an External World is that the argument fails because anyone who had doubts about its conclusion could not use the argument to rationally overcome those doubts. I agree that Moore’s Proof is—in that sense—dialectically ineffective at convincing an opponent or a doubter, but I defend that the argument (even when individuated taking into consideration the purpose of Moore’s arguing and, consequently, the preferred addressee of the Proof) does not (...) fail. The key to my defence is to conceive the Proof as addressed to subjects with a different epistemic condition. To sustain this view I formulate some hypothesis about the common general purpose of arguing and I defend that it can be fulfilled even when the addressee of an argument is not someone who disbelieves or doubts its conclusion. (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)

This paper argues that we should reject G. E. Moore’s anti-skeptical argument as it is presented in “Proof of an External World.” However, the reason I offer is different from traditional objections. A proper understanding of Moore’s “proof” requires paying attention to an important distinction between two forms of skepticism. I call these Ontological Skepticism and Epistemic Skepticism. The former is skepticism about the ontological status of fundamental reality, while the latter is skepticism about our empirical (...) knowledge. Philosophers often assume that Moore’s response to “external world skepticism” deals exclusively with the former, not the latter. But this is a mistake. I shall argue that Moore’s anti-skeptical argument targets an ontological form of skepticism. Thus, the conclusion is an ontological claim about fundamental reality, while the premises are epistemic claims. If this is correct, then the conclusion outstrips the scope of its premises and proves too much. (shrink)

In the third Meditation once having arrived at the conclusion that a perfect being exists, Descartes infers that this perfect being could not be a deceiver. I maintain that there is no valid way he can move from his conclusion that a perfect being exists to the conclusion that this being cannot be a deceiver. In order to see the difficulties with this inference it is necessary to examine the use of the idea of perfection in the argument for the (...) existence of the perfect being, but I will not otherwise concern myself with the validity of the argument for the existence of God. (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)

A critical discussion of selected chapters of the first volume of Scott Soames’s Philosophical Analysis in the Twentieth Century. It is argued that this volume falls short of the minimal standards of scholarship appropriate to a work that advertises itself as a history, and, further, that Soames’s frequent heuristic simplifications and distortions, since they are only sporadically identified as such, are more likely confuse than to enlighten the student. These points are illustrated by reference to Soames’s discussions of Russell’s logical (...) system and the place of the theory of descriptions in his ontological development. It is then argued that Soames’s interpretation of the point of G.E. Moore’s famous “proof” of an external world, while not straightforwardly undermined by the textual evidence, is nonetheless questionable, and plausibly overlooks what is novel in Moore’s discussion. This, it is argued, in his attempt to offer a common sense “refutation of idealism”, rather than (as is more commonly supposed) an anti-skeptical argument “from differential certainty”. (shrink)

Realism, defined as a justified belief in the existence of the external world, is jeopardized by ‘meaning rationalism,’ the classic theory of meaning that sees the extension of words as a function of the intensions of individual speakers, with no way to ensure that these intensions actually correspond to anything in the external world. To defend realism, Ruth Millikan ( 1984 , 1989a , b , 1993 , 2004 , 2005 ) offers a biological theory of (...) meaning called ‘teleosemantics’ in which words, without requiring any contribution from the speaker’s intensions, are supposedly matched directly with their extensions by external norms. But even if one granted as a theoretical possibility that word meaning might possibly be stabilized through an external process, nonetheless, realists who wish to appeal to teleosemantics for a semantic proof of the external world must be capable of identifying these external norms, something that Millikan describes as highly fallible. Furthermore, because they can be aware of these norms only as these are internally represented, it would also be necessary for realists to verify that these internal representations accurately reflect the norms as they occur in the external world. But given that this is virtually the same stumbling block to realism found in meaning rationalism, it is concluded that teleosemantics is not likely to restore faith in this worldview. (shrink)

In Descartes's _Third Meditation, the mediator states that he may have unknown faculties that could cause his ideas of corporeal things. His proof of the external world in the _Sixth Meditation, however, clearly relies on the assumption that he does not have such unknown faculties. This paper examines Lex Newman's attempt to resolve this apparent inconsistency. I argue that the attempt is not altogether successful.

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)

I argue that descartes' doubting of the external world does not rest on doubting the truth of clear and distinct ideas. in fact, he denies that we clearly and distinctly perceive the "existence" of material things. thus, their existence is not established through the validation of such ideas and we can understand why descartes' argument for their existence takes the form it does. i suggest that dreams lead him to conclude that the existence of material things is not (...) clearly perceived and to doubt their existence. (shrink)

The current standard interpretation of Moore’s proof assumes he offers a solution to Kant’s famously posed problem of an external world, which Moore quotes at the start of his 1939 lecture “Proof of an External World.” As a solution to Kant’s problem, Moore’s proof would fail utterly. A second received interpretation imputes an aim of refuting metaphysical idealism that Moore’s proof does not at all achieve. This study departs from received interpretations to (...) credit the aim Moore announced for the proof Moore performed in his 1939 lecture. Moore’s aim was to impose a counter-example to a stated presupposition of Kant’s problem of an external world. Moore’s lecture nevertheless neither endorses a replacement for Kant’s problem nor acknowledges that an immediate implication of achieving his announced aim would subvert Kant’s famously posed problem of an external world. (shrink)

The current standard interpretation of Moore’s proof assumes Moore offers a solution to Kant’s famously posed problem of an external world, which Moore quotes at the start of his 1939 lecture “Proof of an External World.” As a solution to Kant’s problem, Moore’s proof fails utterly. Similarly, a second received interpretation imputes an aim of refuting metaphysical idealism that Moore’s proof does not at all achieve. This study departs from the received interpretations (...) to credit Moore’s stated aim for the proof Moore performed in his 1939 lecture that is to impose a counter-example to an explicitly stated presupposition of Kant’s famously posed problem of an external world. The outcome would therefore subvert Kant’s problem. There is not, however, any rival external world problem that Moore commends in place of Kant’s problem. (shrink)

Alice Ambrose once criticized Moore for treating the proposition ‘There are external objects’ as an empirical one. She said that those who denied that we could know this proposition to be true would not accept any evidence as going against their denial of it, and were not regarding the issue of its truth as empirical. She also maintained that one could not point out an external object in the way in which one could point out a dime or (...) nickel and alleged on these grounds that saying that there are external objects is not the same sort of thing as saying that there are coins. The issue arose concerning Moore's paper, “Proof of an External World.“In “Reply to My Critics,” Moore pointed out that he had been concerned in “Proof of an External World” not to prove that we know that there are external objects, but rather to prove that there are external objects. But he applied Ambrose's remarks to that proposition. Moore rightly asserted that the fact that someone denies that there are external objects and treats all evidence as irrelevant to the issue does not show that the proposition he denies fails to be empirical. (shrink)

The current standard interpretation of Moore’s proof assumes he offers a solution to Kant’s famously posed problem of an external world, which Moore quotes at the start of his 1939 lecture “Proof of an External World.” As a solution to Kant’s problem, Moore’s proof would fail utterly. A second received interpretation imputes an aim of refuting metaphysical idealism that Moore’s proof does not at all achieve. This study departs from received interpretations to (...) credit the aim Moore announced for the proof Moore performed in his 1939 lecture. Moore’s aim was to impose a counter-example to a stated presupposition of Kant’s problem of an external world. Moore’s lecture nevertheless neither endorses a replacement for Kant’s problem nor acknowledges that an immediate implication of achieving his announced aim would subvert Kant’s famously posed problem of an external world. (shrink)

The core idea of the ontological proof is to show that the concept of existence is somehow contained in the concept of God, and that therefore God’s existence can be logically derived—without any further assumptions about the external world—from the very idea, or definition, of God. Now, G.W. Leibniz has argued repeatedly that the traditional versions of the ontological proof are not fully conclusive, because they rest on the tacit assumption that the concept of God is (...) possible, i.e. free from contradiction. A complete proof will rather have to consist of two parts. First, a proof of premiseGod is possible. Second, a demonstration of the “remarkable proposition”If God is possible, then God exists. The present contribution investigates an interesting paper in which Leibniz tries to prove proposition. It will be argued that the underlying idea of God as a necessary being has to be interpreted with the help of a distinguished predicate letter ‘E’ as follows:\\). Proposition which Leibniz considered as “the best fruit of the entire logic” can then be formalized as follows:\) \rightarrow \, E)\). At first sight, Leibniz’s proof appears to be formally correct; but a closer examination reveals an ambiguity in his use of the modal notions. According to, the possibility of the necessary being has to be understood in the sense of something which possibly exists. However, in other places of his proof, Leibniz interprets the assumption that the necessary being is impossible in the diverging sense of something which involves a contradiction. Furthermore, Leibniz believes that an »impossible thing«, y, is such that contradictory propositions like \\) and \\) might both be true of y. It will be argued that the latter assumption is incompatible with Leibniz’s general views about logic and that the crucial proof is better reinterpreted as dealing with the necessity, possibility, and impossibility of concepts rather than of objects. In this case, the counterpart of turns out to be a theorem of Leibniz’s second order logic of concepts; but in order to obtain a full demonstration of the existence of God, the counterpart of, i.e. the self-consistency of the concept of a necessary being, remains to be proven. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Reviewed by:Kant’s Transcendental Proof of RealismBrandon C. LookKenneth R. Westphal. Kant’s Transcendental Proof of Realism. New York: Cambridge University Press, 2004. Pp. x + 299. Cloth, $80.00.Westphal's book is a rich and exciting contribution to the field of Kant studies. Its claims run counter to much contemporary discussion of Kant's theoretical philosophy and indeed challenge some of Kant's fundamental doctrines, but the arguments are very compelling and (...) therefore likely to force us to rethink both the Critique of Pure Reason [CPR] and Kant's relevance to contemporary epistemology.The central point of this work is that, if we follow Kant's injunction to engage in reflection on our cognitive capacities, then we will be led not to Kantian transcendental idealism but to an unqualified realism about objects and events in space and time. The book's first three chapters are devoted to analyzing Kant's methodology and the much-overlooked idea of transcendental affinity. Westphal focuses on the Kantian duty of engaging in "transcendental reflection," which is "the action through which I make the comparison of representations in general with the cognitive power in which they are situated, and through which I distinguish whether they are to be compared with one another as belonging to pure understanding or to sensible intuition" (CPR, A 261/B 317). And he adds to this the more general methodological obligation of "epistemic reflection," or the duty to determine precisely our cognitive capacities and incapacities. If, then, we reflect on our representations, their origins in sensibility and the understanding, and on our powers to know things of ourselves and the world in general, then certain puzzles arise—puzzles that were confronted by Kant (and Hume and Hegel) but that have not received the attention they have deserved. Chief among these puzzles is our ability to identify single objects and events and track them in space through time. But, as Westphal is keen to point out, identifying any particular over time requires that we be able to re-identify that particular. Now, while this puzzle is addressed by Kant in the Transcendental Deduction and Analogies of Experience, it is important to see that there is a material condition necessary for the possibility of self-conscious experience of the world that is not fleshed out in great detail by Kant and seems to be completely overlooked in the literature on Kant, namely, "the presupposition of diversity in nature" and the homogeneity of its objects among themselves (CPR, A 657/B 685). In other words, the fact that we are able to associate our various sensations with each other at all (and thereby identify and re-identify objects) is due to their "transcendental affinity." And it is Westphal's contention that "on Kant's own principles, the transcendental affinity of the manifold of sensory intuition can only be reconstructed, but not constructed, by intellectual syntheses of the understanding" (91). Therefore, pace Kant, who held that only his transcendental idealism could explain the possibility of experience, Westphal argues that transcendental idealism runs afoul of many of Kant's own arguments and observations in the Transcendental Aesthetic and Transcendental Analytic and, more important, that transcendental affinity provides grounds for "realism sans phrase" (the author's phrase) about objects and events in space and time, and for the view that our mental states are determined by external objects. As Westphal puts it in his conclusion: "Kant's analysis of transcendental affinity is in fact a transcendental argument for mental content externalism" (266). [End Page 665]The second part of Westphal's argument revolves around a detailed examination of Kant's theses about transeunt causality and the nature of matter as expressed not only in the Critique of Pure Reason, but also in the Metaphysical Foundations of Natural Science and the Opus postumum. Roughly the problem is this: in order to have an adequately grounded metaphysics of nature, Kant needs not only the results of the Analogies of Experience, the transcendental causal thesis that every event has a cause, but also the metaphysical causal thesis that every physical event has an external physical cause. But, according to Westphal, in the Metaphysical Foundations... (shrink)

This paper considers the analogies and disanalogies between a certain sort of argument designed to oppose scepticism about free will and a certain sort of argument designed to oppose scepticism about the external world. In the case of free will, I offer the ancient Lazy Argument and an argument of my own, which I call the Agency Argument, as examples of the relevant genre; and in the case of the external world, I consider Moore’s alleged (...) class='Hi'>proof of an external world. I draw attention to analogies and disanalogies between the arguments offered in each case in order to suggest that although the Agency Argument shares with its Moorean relative the unfortunate property of being dialectically ineffective against some of those it is mainly hoping to convince, it will not be dialectically ineffective against all of them. It is also argued that the Agency Argument is less vulnerable than Moore’s proof to worries about its justificatory structure. (shrink)

RRecently, much work has been done on G.E. Moore’s proof of an external world with the aim of diagnosing just where the Proof ‘goes wrong’. In the mainstream literature, the most widely discussed debate on this score stands between those who defend competing accounts of perceptual warrant known as dogmatism and conservativism. Each account implies a different verdict on Moore’s Proof, though both share a commitment to supposing that an examination of premise-conclusion dependence relations will (...) sufficiently reveal what’s wrong with the Proof. Parallel to this debate on Moore stands perhaps an equally interesting debate within which the Proof is critiqued as it stands in the context of the skeptical debate. On this score, Michael Fara and Ernest Sosa have weighed in with a markedly different take on Moore’s anti-skeptical ambitions and on the nature of skeptical challenges more generally. The aim of this paper will be to critically evaluate these two very distinct strands of recent work on Moore’s Proof. Part I of the paper will focus on the mainstream debate, and in Part II of the paper, I’ll focus on the parallel debate about skepticism. My critical discussion will be aimed throughout at showing how the various proposals I’ve taken as representative of these two parallel debates surrounding Moore’s Proof ultimately fall short—each for different reasons—of what a satisfactory diagnosis of the Proof would require. (shrink)

Moore's 'Proof of an External World' has evoked a variety of responses from philosophers, including bafflement, indignation and sympathetic reconstruction. I argue that Moore should be understood as following Thomas Reid on a variety of points, both epistemological and methodological. Moreover, Moore and Reid are exactly right on all of these points. Hence what I present is a defence of Moore's 'Proof', as well as an interpretation. Finally, I argue that the Reid-Moore position is useful for (...) resolving an issue that has recently received attention in epistemology, namely, how is it that one knows that one is not a brain in a vat? (shrink)

Two major arguments have been advanced for the claim that there is a transmission failure in G.E. Moore’s famous proof of an external world. The first argument, due to Crispin Wright, is based on an epistemological doctrine now known as ‘conservatism’. Proponents of the second argument, like Nicholas Silins, invoke probabilistic considerations, most important among them Bayes’ theorem. The aim of this essay is to defend Moore’s proof against these two arguments. It is shown, first, that (...) Wright’s argument founders because one of its premises, viz., conservatism, invites scepticism and must therefore be rejected. Then the probabilistic argument is challenged, not because its formal part is dubious, but rather on the grounds that it incorporates an unconvincing philosophical claim as an implicit premise. Finally, the two most promising objections to dogmatism—the negation of conservatism—are repudiated. (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)

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)

Contextualist responses to skepticism about the external world are inadequate, and we should prefer an invariantist response to skepticism. There are two kinds of contextualism---anti-theoretical and theoretical. Anti-theoretical contextualists argue that the principles on which skepticism depends are absent from our ordinary epistemic ways of thinking. So anti-theoretical contextualists conclude that the burden of proof is on the skeptic. But some argue that the principles on which skepticism depends are not absent from our ordinary ways of thinking. (...) The existence of this unresolved dispute suggests that anti-theoretical contextualists have not shifted the burden of proof to the skeptic. Anti-theoretical contextualists also fail to refute skepticism outright. Their primary argument here is one in which the notion of certainty plays a key role. But their argument is unsound on all significant uses of the word 'certain.' Thus, anti-theoretical contextualists have neither refuted skepticism nor shifted the burden of proof to the skeptic. ;Theoretical contextualism claims that the solution to skeptical puzzles lies in the fact that the standards for knowledge shift from context to context. Yet if theoretical contextualist solutions are to be adequate, they must explain how those standards shift. Unfortunately, theoretical contextualism fails to provide this explanation. This explanatory failure, along with the problems that face individual theoretical contextualist accounts, shows that theoretical contextualist responses to skepticism are inadequate. ;Even though contextualism fails, a Moorean invariantism---according to which the standards for knowledge are always low---allows us to know across contexts the things we ordinarily take ourselves to know. We should prefer this Moorean invariantism over contextualism. It stands on the same theoretical ground as the dominant contextualisms while still allowing us to explain how we know that certain skeptical hypotheses are false. Also, contextualism raises questions---for example, questions concerning how the standards for knowledge shift---that receive only inadequate answers. The Moorean invariantist account does not raise such questions. All of this suggests that the Moorean invariantist response to skepticism is better than any of its contextualist counterparts. (shrink)

Two major arguments have been advanced for the claim that there is a transmission failure in G. E. Moore’s famous proof of an external world. The first argument, due to Crispin Wright, is based on an epistemological doctrine now known as “conservatism.” Proponents of the second argument, like Nicholas Silins, invoke probabilistic considerations, most important among them Bayes’ theorem. The aim of this essay is to defend Moore’s proof against these two arguments. It is shown, first, (...) that Wright’s argument founders because one of its premises, viz, conservatism, invites skepticism and must therefore be rejected. Then the probabilistic argument is challenged, yet not because its formal part is dubious, but rather on the grounds that it incorporates as an implicit premise an unconvincing philosophical claim. Finally, the most promising objection to dogmatism – understood here as the negation of conservatism – is repudiated. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Reviewed by:Kant’s Transcendental Proof of RealismBrandon C. LookKenneth R. Westphal. Kant’s Transcendental Proof of Realism. New York: Cambridge University Press, 2004. Pp. x + 299. Cloth, $80.00.Westphal's book is a rich and exciting contribution to the field of Kant studies. Its claims run counter to much contemporary discussion of Kant's theoretical philosophy and indeed challenge some of Kant's fundamental doctrines, but the arguments are very compelling and (...) therefore likely to force us to rethink both the Critique of Pure Reason [CPR] and Kant's relevance to contemporary epistemology.The central point of this work is that, if we follow Kant's injunction to engage in reflection on our cognitive capacities, then we will be led not to Kantian transcendental idealism but to an unqualified realism about objects and events in space and time. The book's first three chapters are devoted to analyzing Kant's methodology and the much-overlooked idea of transcendental affinity. Westphal focuses on the Kantian duty of engaging in "transcendental reflection," which is "the action through which I make the comparison of representations in general with the cognitive power in which they are situated, and through which I distinguish whether they are to be compared with one another as belonging to pure understanding or to sensible intuition" (CPR, A 261/B 317). And he adds to this the more general methodological obligation of "epistemic reflection," or the duty to determine precisely our cognitive capacities and incapacities. If, then, we reflect on our representations, their origins in sensibility and the understanding, and on our powers to know things of ourselves and the world in general, then certain puzzles arise—puzzles that were confronted by Kant (and Hume and Hegel) but that have not received the attention they have deserved. Chief among these puzzles is our ability to identify single objects and events and track them in space through time. But, as Westphal is keen to point out, identifying any particular over time requires that we be able to re-identify that particular. Now, while this puzzle is addressed by Kant in the Transcendental Deduction and Analogies of Experience, it is important to see that there is a material condition necessary for the possibility of self-conscious experience of the world that is not fleshed out in great detail by Kant and seems to be completely overlooked in the literature on Kant, namely, "the presupposition of diversity in nature" and the homogeneity of its objects among themselves (CPR, A 657/B 685). In other words, the fact that we are able to associate our various sensations with each other at all (and thereby identify and re-identify objects) is due to their "transcendental affinity." And it is Westphal's contention that "on Kant's own principles, the transcendental affinity of the manifold of sensory intuition can only be reconstructed, but not constructed, by intellectual syntheses of the understanding" (91). Therefore, pace Kant, who held that only his transcendental idealism could explain the possibility of experience, Westphal argues that transcendental idealism runs afoul of many of Kant's own arguments and observations in the Transcendental Aesthetic and Transcendental Analytic and, more important, that transcendental affinity provides grounds for "realism sans phrase" (the author's phrase) about objects and events in space and time, and for the view that our mental states are determined by external objects. As Westphal puts it in his conclusion: "Kant's analysis of transcendental affinity is in fact a transcendental argument for mental content externalism" (266). [End Page 665]The second part of Westphal's argument revolves around a detailed examination of Kant's theses about transeunt causality and the nature of matter as expressed not only in the Critique of Pure Reason, but also in the Metaphysical Foundations of Natural Science and the Opus postumum. Roughly the problem is this: in order to have an adequately grounded metaphysics of nature, Kant needs not only the results of the Analogies of Experience, the transcendental causal thesis that every event has a cause, but also the metaphysical causal thesis that every physical event has an external physical cause. But, according to Westphal, in the Metaphysical Foundations... (shrink)

This volume is a collective exploration of major themes in the work of Crispin Wright, one of today's leading philosophers. These newly commissioned papers are divided into four sections, preceded by a substantial Introduction, which places them in the context of the development of Wright's ideas. The distinguished contributors address issues such as the rule-following problem, knowledge of our meanings and minds, truth, realism, anti-realism and relativism, as well as the nature of perceptual justification, the cogency of arguments such as (...) G. E. Moore's celebrated proof of an external world, and skepticism about the material world. Some papers explore the relationship of Wright's ideas with those of Ludwig Wittgenstein, whose influence has always been a prominent aspect of Wright's philosophy. The essays collectively testify to the enormous interest and relevance of Wright's seminal contributions for present-day debates in areas as diverse as the philosophy of language and mind, metaphysics, and epistemology, and significantly advance research in these areas. The volume also contains Wright's substantial responses to his critics, which offer the most up-to-date versions of his ideas and a vigorous defense of his philosophy. (shrink)

Moore’s “Proof of an external world” and his “Four forms of scepticism” have long puzzled commentators. How are these adequate responses to sceptics? How, for that matter, is the so-called proof of an external world even pertinent to the challenge of scepticism? The notion of relativized burdens of proof is introduced: this is a burden of proof vis-à-vis one’s opponent that one takes on when trying to convince that someone of something. The (...) relativized burden of proof is a making explicit the truism that if you argue with someone with the intent of trying to convince that someone of something, and if you fail to, you have not met your own conversational goal. Assuming Moore is implicitly relying on the notion of relativized burdens of proof illuminates his approach in these papers. (shrink)

Contemporary discussions of skepticism often frame the skeptic's argument around an instance of the closure principle. Roughly, the closure principle states that if a subject knows p, and knows that p entails q, then the subject knows q. The main contention of this paper is that the closure argument for skepticism is defective. We explore several possible classifications of the defect. The closure argument might plausibly be classified as begging the question, as exhibiting transmission failure, or as structurally inefficient. Interestingly, (...) perhaps, each of these has been proposed as the correct classification of Moore's proof of an external world. (shrink)

Cartesian epistemology comprises three main divisions: an a priori theory, discussed in Chs. 1–3, a psychological theory of error explanations in judgment induced by features of our sense experience discussed in Chs. 4, 5 and 7, and a theory of natural reasons, discussed here. The theory of natural reasons, based on Descartes's notion of natural inclinations, is expressed here in terms of a series of warrant principles of which there are two main kinds: those that warrant action and those that (...) warrant claims for what is true. This chapter traces Descartes's epistemically ambivalent attitude to cognitive dispositions from the early treatment in the Rules for the Direction of the Mind through to the final treatment in The Passions of the Soul. The chapter focuses special attention on the appearance of one kind of natural reason, reasons of truth, in the proof of the external world in Meditation VI and the striking absence of same in the proof of the external world in the Principles of Philosophy II. The chapter also considers whether natural reasons apply to particular aspects of corporeal things, concluding with a discussion of the Cartesian Circle. (shrink)