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.

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)

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)

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)

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)

One of the most important views in the recent discussion of epistemological scepticism is Neo-Mooreanism. It turns a well-known kind of sceptical argument (the dreaming argument and its different versions) on its head by starting with ordinary knowledge claims and concluding that we know that we are not in a sceptical scenario. This paper argues that George Edward Moore was not a Moorean in this sense. Moore replied to other forms of scepticism than those mostly discussed nowadays. His (...) own anti-sceptical position turns out to be very subtle and complex; furthermore it changed over time. This paper follows Moore's views of what the sceptical problem is and how one should respond to it through a series of crucial papers with the main focus being on Moore's 'Proof of an External World'. An appendix deals with the much neglected relation between epistemological scepticism and moral scepticism in Moore. (shrink)

G.E. Moore, more than either Bertrand Russell or Ludwig Wittgenstein, was chiefly responsible for the rise of the analytic method in twentieth-century philosophy. This selection of his writings shows Moore at his very best. The classic essays are crucial to major philosophical debates that still resonate today. Amongst those included are: * A Defense of Common Sense * Certainty * Sense-Data * External and Internal Relations * Hume's Theory Explained * Is Existence a Predicate? * Proof of an (...) class='Hi'>External World In addition, this collection also contains the key early papers in which Moore signals his break with idealism, and three important previously unpublished papers from his later work which illustrate his relationship with Wittgenstein. (shrink)

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)

G. E. Moore was one of the most interesting and influential philosophers of the first half of the twentieth century. This selection of his writings makes the best of his work once again available, and also includes previously unpublished writings. Moore's first published writings, represented in this collection by his papers "The Nature of Judgment" and "The Refutation of Idealism," contributed decisively to the break with idealism which led to the development of analytic philosophy. Moore went on to develop his (...) own style, which combined a defense of the common sense view of the world with a controversial analysis of the content of this view. Also included is Moore's famous "Proof of an External World," which marked a return late in his career to the critique of idealism. Other papers address perception and important issues in logical theory. The collection ends with three new pieces which illustrate Moore's relationship with Wittgenstein. In these pieces Moore discusses his "paradox" whichso fascinated Wittgenstein; the nature of our knowledge of our own sensations; and Malcolm's views about doubt and knowledge which were themselves inspired by Wittgenstein. (shrink)

Once, G. E. Moore scorned the “common point of view which takes the world of experience as ultimately real.” The argument Moore followed to this sceptical conclusion in his fledgling 1897 fellowship dissertation was a legacy from Kant's Antinomies. By 1899 Moore had renounced idealist conclusions; he set out both to disengage from Kantian arguments and to reconcile with “the world of experience.” Moore's work for a stable realist basis for knowledge to fulfil both aims occupied his most (...) famous argument, in his 1939 lecture “Proof of an External World.” Moore himself is sometimes supposed to have thought the argument of this masterwork unsatisfactory where it treats a traditional sceptical puzzle posed by dreaming. Critics, including Wittgenstein, have portrayed Moore's best reply to philosophical scepticism as dogmatic mere assertion, unresponsive or as ineffectual as sheer handwaving. However, these critics rate Moore's success against scepticism based on interpretations of “Proof of an External World” that neglect its part in Moore's campaign against Kant. Consequently, some potentially pivotal questions — which in this study I merely broach — remain wide open; for example, why in presenting his famous 1939 proof did Moore state that its purpose was to refute what “Kant declares to be his opinion, that there is only one possible proof of the existence of things outside of us”? And why did Moore explicitly reject the formula for posing philosophical scepticism in which Kant famously proclaimed this problem “a scandal to philosophy”? (shrink)

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)

G.E. Moore, more than either Bertrand Russell or Ludwig Wittgenstein, was chiefly responsible for the rise of the analytic method in twentieth-century philosophy. This selection of his writings shows Moore at his very best. The classic essays are crucial to major philosophical debates that still resonate today. Amongst those included are: * A Defense of Common Sense * Certainty * Sense-Data * External and Internal Relations * Hume's Theory Explained * Is Existence a Predicate? * Proof of an (...) class='Hi'>External World In addition, this collection also contains the key early papers in which Moore signals his break with idealism, and three important previously unpublished papers from his later work which illustrate his relationship with Wittgenstein. (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)

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)

Does scepticism threaten our common sense picture of the world? Does it really undermine our deep-rooted certainties? Answers to these questions are offered through a comparative study of the epistemological work of two key figures in the history of analytic philosophy, G. E. Moore and Ludwig Wittgenstein.

Suppose one has a visual experience as of having hands, and then reasons as follows: I have hands, If I have hands an external world exists; An external world exists. Suppose one’s visual experience gives one defeasible perceptual warrant, or justification, to believe – that is, one’s experience makes it epistemically appropriate to believe . And suppose one comes to believe on the basis of this visual experience. The conditional premise is knowable a priori. And can (...) be established by modus ponens inference. If one reasons thus, say one’s engaged in -reasoning. What, if anything, is wrong with -reasoning? I consider two prominent responses to this question – the dogmatists’ and Crispin Wright’s. Each finds fault in -reasoning, but on different grounds. I argue Wright’s response faces a problem which is standardly only taken to be faced by dogmatists. (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)

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)

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 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)

(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.

Book description: * G. E. Moore is a key figure in analytic philosophy * Sixteen specially written essays reflect the current resurgence of interest in Moore 's work * Superb international line-up of contributors * A valuable resource for anyone working in epistemology or ethics These sixteen original essays, whose authors include some of the world's leading philosophers, examine themes from the work of the Cambridge philosopher G. E. Moore, and demonstrate his considerable continuing influence on philosophical debate. Part (...) I bears on epistemological topics, such as scepticism about the external world, the significance of common sense, and theories of perception. Part II is devoted to themes in ethics, such as Moore 's open question argument, his non-naturalism, utilitarianism, and his notion of organic unities. (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)

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)

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 (...) class='Hi'>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)

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)

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)

G. E. Moore famously offered a strikingly straightforward response to the radical sceptic which simply consisted of the claim that one could know, on the basis of one's knowledge that one has hands, that there exists an external world. In general, the Moorean response to scepticism maintains that we can know the denials of sceptical hypotheses on the basis of our knowledge of everyday propositions. In the recent literature two proposals have been put forward to try to (...) accommodate, to varying extents, this Moorean thesis. On the one hand, there are those who endorse an externalist version of contextualism, such as Keith DeRose, who have claimed that there must be some contexts in which Moore is right. More radically still, Ernest Sosa has expanded on this externalist thesis by arguing that, contra DeRose's contextualism, Moore may be right in all contexts. In this paper I evaluate these claims and argue that, suitably modified, one can resurrect the main elements of the Moorean anti-sceptical thesis. (shrink)

First published in 2002. Routledge is an imprint of Taylor & Francis, an informa company.

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)