BERKELEY’S PARADOX: EXTERNAL WORLD SKEPTICISM AND THE PROBLEM OF EPISTEMIC JUSTIFICATION

How can I ever be certain that there is anything at all external to my own thoughts? Many philosophers have either tried to advance a proof of the ex ternal world, or to dis miss the intelligibility of the very idea of a “proof” in this context. The aim of this paper is to show that the so-called “problem of the external world” arises out of a misleading conception of epistemic justification. I present an analysis of what I call “Berkeley’s paradox” in order t o show that the ordinary use of language should not work as the standard of correctness for the application of concepts such as knowledge and existence. I conclude that both the traditional attempts to provide a proof for the existence of the external world and the attempts to dismiss the problem as meaningless are mistaken. What has to be taken into account in the examination of the external world is the c ontext within which the skeptical contention is raised.


Introduction
When I think about anything, do the things I think about also exist outside of my mind?How can I ever be certain that there is anything at all external to my own thoughts?The so-called "problem of the external world" was firstly posed by Descartes in the Meditations.Descartes himself offered a proof for the existence of the external world in the Sixth Meditation.Some philosophers after Descartes have attempted solve the problem by advancing a different proof of the external world.Kant, for instance, argued in the preface to the Critique of Pure Reason that it was a "scandal" that no compelling philosophical proof of the existence of the external world had ever been put forth before him. 1 Kant, then, advances his own proof for the existence of the external world in a section of the Critique of Pure Reason called "Refutation of idealism".In the twentieth century G. E. Moore also proposed a different argument for the existence of the external world.He published a well-known article entitled "Proof of an external world" in 1939. 2 Some philosophers, on the other hand, did not try to prove the existence of the external world.They have rather tried to show that the very idea of a "proof" of the external word does not make any sense.Wittgenstein, for instance, dismissed Moore's ideia of a "proof" of the external world in On Certainty. 3Heidegger, too, criticized the very idea of a proof of the external world in the §43 of Being and Time.Heidegger goes as far as to argue that the "scandal" of philosophy is the attempt to advance such a proof in the first place: "The 'scandal of philosophy' does not consist in the fact that this proof is still lacking up to now, but in the fact that such proofs are expected and attempted again and again." 4 1 KANT, 1999, p. 121 (K.r.V. B, xxxix): "No matter how innocent idealism may b e held to be as regards the essential ends of metaphysics (though in fact it is not so innocent), it always remains a scandal of philosophy and universal human reason that the existence of things outside us (from which we af ter all get the whole matter for our cognitions, even for our inner sense) should have to be assumed merely on faith, and that if it occurs to anyone to doubt it, we should be un-able to answer him with a satisfactory proof." 2 MOORE, 1939. 3 WITTGENSTEIN, 1984. 4 HEIDEGGER, 1996, p. 190. See also Heidegger 1996, p. 191: "The 'problem of reality' in the sense of the question of whether an ext ernal world is object ively present or demon strable, turns out to be a n I do not intend to examine here all these reactions to the so-called "problem of the external world".My intention here is, rather, to show that the problem of the external world, as it was posed by Descartes in the Meditations, arises out of a misleading conception of epistemic justification.

The mind-world gap
One argument against the very idea of a proof of the external world consists of two steps.The first step is statement of the problem: [a] external world skepticism can only emerge if an essential distinction between "ideas" and "objects" is taken for granted; for [b] what we directly perceive are not the objects themselves, but our ideas of objects; hence [c] we have to prove that the ideas we perceive in ourselves do correspond to the objects they represent and that are supposed to exist outside of ourselves.The second step against the very idea of a proof of the external, then, is to dismiss the starting point, namely: do deny the supposition that there is a sort of ontological gap between the world, on the one hand, and the mind, on the other.George Berkeley, as I will show later on in this article, seems to have been the first philosopher to propose a refutation of external world skepticism along these lines.But, as I intend to show, external world skepticism does not originate from the assumption of a mind-world gap.External world skepticism arises from one's acceptance of a peculiar understanding of what epistemological justification means.
Let us consider the following example: I think that I have a hand.But am I really epistemically entitled to accept the proposition p "I have a hand" as a piece of knowledge?In other words, do I really know that I have a hand?Although I cannot deny that I do think that I have a hand, maybe this thought does not have any counterpart in the external world.Maybe there is something I am not aware of that is the cause of the thought about an object that does not really exist outside of myself.According to a traditional conception of epistemic justification, in order to justify p I must be able show that there is not any proposition q (let q be, for instance, "there is an evil god which deceives me all the time") such that, if q is true, then I am not impossible one, not because its consequences led to inextricable impasses, but because the very being which serves as its theme repudiates such a line of questioning, so to speak."See also MCDOWELL,  1986; MCDOWELL, 1994; BURGE, 1986.entitled to accept p as true.As long as I am not able to prove that ~q, I do not know that p. Descartes endorsed this traditional conception of epistemic justification.He assumed that knowing that p implies that there is not the slightest possibility that ~p.5 For a person S to be justified in accepting that p as a piece of knowledge it is necessary, according to Descartes, that there is not any true proposition q such that q is contrary to the proposition S knows that p. Two propositions are called "contrary" if they cannot be simultaneously true, although they can be simultaneously false. 6They are contrary because, if it is true that S knows that p, then it is false that q.Conversely, if this is the case that q, then S knows that p must be false.But, since these are contrary propositions, it may also be the case that both S knows that p and q are simultaneously false.This will happen when the falsity of S knows that p results from some reason other than the truth of q.In other words, the simple fact that S knows that p is false does not entail that q is true.Other propositions such as, for instance, r "my brain is being manipulated by a mad scientist whenever I make a knowledge claim" may have the same "disqualifying" power as the proposition q. 7 Descartes' theory of knowledge, therefore, presupposes that if someone knows that p, then there is not any true proposition q, such that, if q is true, then p cannot be justifiably accepted as a piece of knowledge.Now, in order to advance some general doubt concerning the justifiability of our knowledge claims, on the grounds that, unless we are in condition to prove ~q, we are not entitled to assume any proposition p as a piece of knowledge, it is not necessary to assume that there is a sort of gap between the mind and the reality outside of the mind.All that is required in order to advance a general doubt concerning the justifiability of our knowledge claims is that, in our conception of knowledge, being justified in accepting that p rules out the slightest possibility that ~p.Since the 1960's much has been written on the problem of epistemic justification.Thus, it would be worth turning our attention for a moment to some aspects of this debate.

Gettier's Problem
Gettier's landmark paper, entitled "Is justified true belief knowledge?",published in 1963, has had a great influence on the debate on the concept of epistemic justification.8Gettier presents two counter examples to the traditional idea that knowledge should be comprehended in terms of justified true belief.According to the traditional conception of knowledge we can say that S knows that p if and only if: (i) S believes that p (ii) p is indeed true (iii) is justified in believing that p Gettier's argument consists in showing that in some situations, even though the three conditions obtain, S does not know that p.Let us consider the following example: John looks at a red object and assumes that he is justified in affirming the following proposition: "The object I see is red".9Now, the three aforementioned conditions obtain, viz.[1] John believes the object in question is red; [2] this object is in fact red; and [3] John, relying upon his eyesight, considers the proposition p to be fully justified.But let us suppose further that, unbeknownst to John, this object is illuminated by a red light, so that he would have had the very same impression that this object is red whatever its color is.Thus, even though the three traditional conditions for raising a knowledge claim are fulfilled here, we cannot say that John knows that p, because it is just matter of chance that the object in question is actually red.Keith Lehrer sums up Gettier's argument in the following terms: To put the argument schematically, Gettier argues that a person might be completely justified in accepting that F by her evidence, where F is some false statement, and deduce T from F, where T is some true statement.Having deduced T from F, which she was completely justified in accepting, the person would then be completely justified in accepting that T. Assuming that she accepts that T, it would follow from the analysis that she knows that T. In such a case, the belief that T will be true, but the only reason the person has for accepting T to be true is the inference of T from F. Since F is false, it is a matter of luck that she is correct in her belief that T. 10 Since its publication Gettier's paper gave rise to a huge debate on the nature of epistemic justification.It is not my intention here to resume every aspect of this debate. 11The point I want to stress is simply that what enabled Descartes to put the existence of the external world into question, in the Mediations, is the same kind of presupposition that underlies the problem to which Gettier calls attention, namely: the idea that in order to justify p one must exclude every possibility that there is a proposition q such that, if q is true, then one does not really know that p.In the example above, the proposition that must be excluded is "the object I see is illuminated by a red light".There might certainly be other true propositions of this kind (e.g.q "there are red lenses between my eyes and the object I see").For the traditional conception of epistemic justification every one of these propositions would have to be ruled out if John is to be justified in affirming the proposition "the object I see is red".This kind of skepticism does not have to endorse the existence of a gap between the mind and the reality outside of the mind.

Berkeley on the "very root‰ of skepticism
In the First Meditation, Descartes advances an argument for general skepticism.No proposition is accepted as true at the end of the First Meditation.At this stage of Descartes' argument the general skeptical doubt stems from the traditional conception of epistemic justification.Yet, it is not external world skepticism.It is in the Second Meditation that Descartes claims to have proved his own existence as a thinking subject.Thus, the question he tries examine next is whether anything that is thought of does really exist independently of being thought of.It is only at this stage of his argument that "external world skepticism" arises.If this interpretation of Descartes' argument is correct, then the gap between the mind and the world should not be viewed as the "very root" of the external world skepticism, as Berkeley proposed in A Treatise Concerning the Principles of Human Knowledge (1710).External world skepticism results, rather, from a problematic understanding of epistemic justification.Berkeley refers to the "very rood‰ of skepticism in the following passage: This, which, if I mistake not, hath been shewn to be a most groundless and absurd notion, is the very root of scepticism; for, so long as men thought that real things subsisted without the mind, and that their knowledge was only so far forth real as it was conformable to real things, it follows they could not be certain they had any real knowledge at all.For how can it be known that the things which are perceived are conformable to those which are not perceived, or exist without the mind? 12ntrary to BerkeleyÊs understanding of the skeptical doubt, my own view is that the "root" of Cartesian skepticism must be sought in the supposition that to be justified in accepting a proposition as a piece of knowledge means being able to exclude the possibility that there is some true proposition which would discredit as piece of knowledge the proposition we intend to justify.According the traditional conception of knowledge, as we saw above, if the proposition q "the object I see is illuminated by a red light" is true, then it discredits the proposition p "this object I see is red" as a piece of knowledge, even though p may be in fact true.In the First Meditation, Descartes assumes that he is not justified in accepting the proposition "I have a hand" as a piece of knowledge as long as the proposition "there is an evil god which deceives me all the time" has not been ruled out.

Berkely's Paradox and the ordinary use of language
If external world skepticism results from a problematic understanding of epistemic justification, rather than from the assumption of a mind-world gap, then the question we should examine now is why the traditional conception of epistemic justification is wrong.It might be argued that the traditional conception of epistemic justification, as it was endorsed, for instance, by Descartes, departs from the ordinary use of language.The idea here is that the skeptic seems to introduce a new understanding of epistemic justification.But why should we accept this new understanding of epistemic justification in the first place?Peter Strawson, for instance, suggests that the skeptic is not talking about our knowledge of the world, but rather proposing "a fairly drastic revision of our ordinary scheme of things". 13This "drastic revision", it might be argued against the skeptic, is an unjustified philosophical construction.The problem, however, is that saying that the skeptic makes a kind of philosophical construction does not by itself imply that the ordinary language is reliable standard for the correct application of concepts such as "knowledge", "justification", and "existence".Ordinary language itself may be quite incoherent and, indeed, contaminated by problematic philosophical assumptions.Let us consider, for instance, these two accounts of epistemic justification: Roth and Ross  [ii] Lehrer One popular answer <sc. to the skeptic> appeals to our ordinary st andards for use of the verb "t o know".If the skeptic requires t hat every possible alternative be ruled out with hard evidence in order to claim knowledg e, then, of course, knowledge is unattainable.But the simple and undeniable f act is that those are not standards we impose on ourselves when we seek to justify our claims t o know.Fluent speakers of English use the locution "I know" with perfect correctness while wholly ignoring the criteria proposed by such a skeptic.The skeptic then appears to be recommending a new standard for the correct usage of "I know" a recommendation which on t he face of it seems absurd si nce if we were to accept the recommendation we could no longer use "I know" correct ly, at least not with regard to statements about the world around us. 14 With this reply to scepticism set forth, we hasten to note that in some way s our position is very close to that of the skeptic, for very often when people claim to know something, they claim to know f or certain.If they do know for certain, then there must be no chance that they are in error.Hence, in ag reeing that there is always some chance of error, we are agreeing with the skeptic that nobody ever knows f or certain that anything is true.Joining hands with the sceptic in this way will win u s no applause fro m those dogmatists who never doubt that people know for certain many of the things they claim to know.
Thus, our t heory of knowledge is a t heory of knowledge without certainty.We agree wit h the sceptic that if a person claims to know for certain, he does not know whereof he speaks.However, when we claim t o know, we ma ke no claim t o certainty.We conjecture that to speak in this way is to departure from the most customary use of the word "know".Commonly, when p eople say that they know, they mean they know for certain and assume that there is no chance of being in error.This assumption enables them to lay aside theoretical doubts and t o pretend they proceed on certain grounds. 15th [i] and [ii] try to call our attention to the ordinary use of knowing.But the problem is that the possibility of there being opposing ordinary linguistic practices, or different opposing views about the correct interpretation of what is required by the ordinary use of language, may lead us back to the very point the skeptic is trying to make.Indeed, for Sextus Empiricus, for instance, the skeptical suspension of judgment, in certain contexts, stems exactly from our inability to decide between different "opposing views". 16Thus, the attempt to avoid the skeptical doubt by resorting the ordinary use of language as the standard for the correct application of concepts such as "knowledge", "justification", and "existence" seems also problematic.This problem concerns what I call the "Berkeley's paradox".
In the Principles Berkeley affirms that the refutation the skepticism must be preceded by an elucidation of those concepts employed in the skeptical argument: Nothing seems of more importance towards erecting a firm system of sound and real knowledge, which may be proof against the assaults of scepticism, than to lay the beginning in a distinct explication of what is meant by thing reality, existence; for in vain shall we dispute concerning the real existence of things, or pretend to any knowledge thereof so long as we have not fixed the meaning of those words.17

But how shall we undertake an elucidation of these concepts, presupposed by the skeptical claim, so as to establish their correct meaning?
Berkeley's answer is simple: we have to observe "the common use of language".18Berkeley also argues that we have to point out the "usual or literal sense" of the words. 19For our words lack meaning whenever they do not conform to "the right use and signifcancy of language".20Thus, once we have established "the proper use of words"21, present for example in the problem of the external world, the skeptical contention will have been proved to be a "vain chimera" 22 , i.e. a sort of meaningless philosophical construction.which, according to Berkerley, "cannot be understood in the common sense of those words" 23 : But all this doubtfulness, so bewilders and confounds our mind, and makes philosophy ridiculous in the eyes of the world, vanishes, if we annex a meaning to our words, and do not amuse ourselves with terms absolute, external, exist, and such like, signifying we know not what. 24wever, although Berkeley argues that a philosophical investigation into the nature of knowledge should not go beyond the ordinary use of language, he also admits, on the other hand, that these philosophical constructions "without any intelligible meaning annexed to it" were already "grafted" in the science of his time. 2519 BERKELEY § 16.See also § 51; "…in such things we ought to 'think with the learned, and speak with the vulgar..'"; and § 37: "It will be urged t hat thus much at least is true, to wit, that we t ake away all corporeal substances.To this my answer is, that if the word substance be taken in the vulgar sense, for a combination of sensible qualities, such as extension, solidity, weight, and t he like; this we c annot be accused of taking away: but if it be taken in a philosophic sense, for the support of accidents or qualities without the mind, then indeed I acknowledge that we take it away, if one may b e said to take away that which never had any existence, not even in the imagination". 20BERKELEY, § 83.See also § 79: 7 answer, when words a re used without a meaning, you may put them together as you please wit hout danger of running into a contradiction.You may say, for example, that twice two is equal to seven, so long as you declare you do not take the words of that proposition in their usual acceptation but for marks of you know not what'. 21BERKELEY, § 83. 22BERKELEY, § 150 23 BERKELEY, §17. 27BERKELEY, § 51: "A little reflection on what is here said will make it manifest, that the common use of language would receive no manner of alteration or disturbance from the admission of our tenets".See also § 97 and §123. 24BERKELEY, § 88.See also Berkeley § 51: "A little reflection on what is here said will make it manifest, that the common u se of language would receive no manner of alteration or dist urbance from the admission of our tenets".See also § 97 and §123. 25BERKELEY, § 125: "These errors <sc."the doctrine of abstract general ideas"> are grafted as well in the minds of geometricians, as of other men, and have a like influence on their reasoning..." Now, if some doctrines or theories, which depart from the proper use of words turn out to become in the course of time the predominant use of language, what are we then expected to do?Should we not in this case make a "drastic revision" of the conceptual framework that make up our new -and also mistaken -ordinary linguistic practices?might be argued that if the "usual or literal sense" of our words become corrupted by some widespread philosophical doctrines, then what we have to strive for is not some much a "drastic revision of our ordinary scheme of things", but rather a recovery of our ordinary linguistic practices.Nevertheless, it seems to me that once we have admitted that philosophical theories have been incorporated into our ordinary framework of concepts -and Berkeley seems to accept this thesis -, how can we then be entirely assured that our everyday epistemic behavior is not already the result of a false conception of knowledge "grafted" on our language?
Perhaps the skeptic does introduce a new use for "knowledge", "existence", "justification", etc.But the problem is that, possibly, we are not in a position to affirm that our language, and our system of knowledge as a whole, have not already been previously contaminated by some "vain chimera".The skeptical use of "knowledge", "existence", and "justification" may after all be what we should ordinarily understand by these words, if the ordinary language had not been contaminated by some "vain chimera" in the first place.Thus, the attempt to discard the problem of the external world as a pseudo problem on the grounds that this problem contains concepts which do not correspond to our ordinary linguistic practice is problematic.This is what I call the "Berkeley's paradox" in the refutation of skepticism: at the same time Berkeley requires that our investigation into the problem of knowledge does not go beyond the "usual or literal sense" of our words -so as to avoid philosophical constructions -he also concedes that what is being investigated may already be the outcome of some philosophical constructions.
It is important to mention now that "Berkeley's paradox" is only one aspect of the problem concerning the relationship between epistemological theories and our ordinary linguistic practice.Even if it is proved that philosophical theories are less present in our ordinary linguistic practice than the formulation of the "Berkeley's paradox" supposes, it might still be argued, against the common sense criticism of the skeptical problem, that maybe it is just a matter of chance that we have the framework of concepts that we have.In other words, the common sense criticism of the problem of the skepticism requires that we attend the proper use of language, so that we realize that the skeptical contention arises out of a misunderstanding concerning some concepts such as "existence", "knowledge", "justification", etc.26But why -we could ask now against common sense criticism -should the ordinary use of language be the standard for the correct application of these concepts?Would it not be dogmatic simply to postulate, without further justification, a criterion for the correct application of a concept solely by an elucidation of our factual use of this concept?Should we not expect from the commonsensical position a justification for the thesis that the traditional use of language is in a certain sense "better" than the alternative introduced by the sceptic?
This attitude towards the commonsensical position can be understood in two different ways: [i] it can be comprehended as a skeptical reply to the common sense criticism.In this case, against common sense criticism, the skeptic would answer that there seems to be no good reason to assume that the ordinary use of language must work as a reliable standard for the application of epistemological concepts.
[ii] But it can also be conceived as an acknowledgement that, although the skeptical challenge cannot be met by common sense criticism, it must be met some other way.In this case, the possibility of having to carry out a "drastic revision of our ordinary scheme of things" -that is introducing new concepts which do not have a counterpart in the ordinary use of language -may be admitted as a valid step.The problem, it might be argued, is that the skeptic seems to perform the wrong kind of revision.I would like now to examine this second attitude towards the common sense criticism of external world skepticism.

"Revision of our ordinary scheme of things‰
A strategy to address the problem of skepticism consists now in calling attention to the diversity of contexts in which the concepts that make up the thrust of the skeptical claim may be applied.The main idea underlying this approach is that the correct application of a concept is determined by the context in which this concept is applied.The correct application of the concept of "knowledge" may differ according to the context in which it is used.In an ordinary context -a context for example where there are normal conditions of illumination and in which my eyesight does not suffer from any kind of perturbation -I can affirm, for instance, that I know that there is a real tree outside my room.However, if for some reason someone I trust tells me that the real trees outside or my room have been replaced by perfect artificial copies, then it seems reasonable to suppose that now, in this new context, I do not actually know that there is a real tree outside my room.In this new context, those pieces of evidence that were enough to justify the knowledge claim in the first context fail to work as acceptable pieces of evidence for my knowledge claim. 27ne important element of the skeptical contention is to argue that when we make a knowledge claim we are not always in a position to assume that we are in a "normal" context.Descartes' argument, for example, calls attention to the possibility that we are constantly deceived by an evil god.The argument, thus, cast doubt on the supposition that we are in a "normal" context when we assert even the most trivial propositions such as "2+2=4" or "the object I see outside of my room is a real tree".For Descartes, a normal context would be one in which we know that we are neither dreaming nor being deceived by an evil god.
When I say that I know that there is a real tree outside of my room I assume that it is not "relevant" to my knowledge claim to consider the possibility that some real trees outside of my room may have been replaced by indistinguishable artificial copies.But if I am informed that many real trees in the vicinity have been replaced by outstanding imitations, then this possibility becomes a "relevant alternative" which I cannot neglect when I make a knowledge claim about the existence of trees outside of my room. 2827 AYER, 1956, p. 32: "Claims to know empirical statements may be upheld by reference to perception, or to memory, or to testimony, or to historical records, or to scientific laws.But such backing is not always strong enough for knowledge.JOHNSEN, 1990, p. 29: "The degree of rigor we expect of ourselves and others in making claims t o knowledge varies with context, and perhaps also with the speaker's intentions.This has seemed to many to provide, at long last, the basis for a definitive response to the sceptic.Roughly, the idea is t hat the Thus, a context is always defined against the background of some relevant alternatives to the knowledge claim at issue.A proposition will be a relevant alternative depending chiefly on the kind of interest we have when we make a knowledge claim.If this is so, then, against the skeptical contention, it seems that we are indeed entitled to affirm that we do know many things, provided only that we attend to the context in which our knowledge claims are made.
David Lewis makes a similar point in the article "Elusive knowledge", published in 1996.In his account of the problem of skepticism, Lewis introduces the notion of a "rule of attention".This rule governs our cognitive practices.His point is that no matter how far-fetched the skeptical hypothesis may sound, as long as our attention is turned to the skeptical hypothesis, our ordinary knowledge claims are put into question.But our knowledge claims are only temporarily destroyed, for most of the time, in our everyday conversations, these skeptical hypotheses are "properly ignored".Given our interests in the course of everyday interaction, it is no problematic to affirm, for instance, that "I have a hand".But in the context of an investigation into the foundations of knowledge, it is our interest to consider some hypotheses that clearly would be out of place in the context of our ordinary knowledge claims.
The problem with the skeptical argument, then, is that it applies the concept of knowledge with such a high standard of rigor that the concept turns out to lie entirely beyond the scope of our ordinary interests.Unlike the commonsensical position towards the problem of skepticism, the relevant alternative approach and the approach proposed by Lewis do not accuse the skeptic of making a philosophical construction, but rather of not specifying the context in which his claim must be considered.In the context of a philosophical investigation into the problem of knowledge it is sometimes part of our interest to introduce a higher degree of rigor, a degree of rigor that, indeed, can be perfectly dispensed with in the course of our ordinary life.Barry Stroud puts this problem in the following terms: sceptic attempts to impose extremely high standards of rigour, and that this yields two possibilities: either those standards are contextually inappropriate, in which case we may simply r eject his claims t hat we don't know; or t hey are appropriat e, in which case t hat very f act shows t he context to be ext remely unusual, even bizarre, and therefore of little concern -most of our claims are not made in such contexts, and are t herefore not threatened.This perspective on cent ral epistemological questions has bec ome known as the relevant view.According to this view, again roughly, to know the truth of some proposition is to be justified in rejecting those alternatives that are relevantly contextually appropriate standards".See also SEE also STINE, 1976.There is a single conception of knowledge at work both in everyday life and in the philosophical investigation of human knowledge, but that conception operates in everyday life under constraints of social practice and the exigencies of action, co-operation and communication.The practical social purposes served by our assertions and claims to know things in everyday life explain why we are normally satisfied with less than what, with detachment, we can be brought to acknowledge are the full conditions of knowledge.From a detached point of view -when only the question of whether we know is at issue -our interests and assertions in everyday life are seen as restricted in certain ways.Certain possibilities are not even considered, let alone eliminated, certain assumptions are shared and taken for granted and so not examined, and our claims are made and understood as if they were restricted to the particular issues that have explicitly arisen. 29 we assume that the correct application of a concept depends on the proper standards of rigor required by the context (or the kinds of interests that we have) and if, in addition to this, we assume that the factual use of our language does not constitute by itself the criterion for the correct application of a concept, then the skeptic may after all be entitled to affirm that, in the context of a philosophical investigation, we do not really know much, if anything at all, about the external world.But we still do know a lot of things about the world in the context of our ordinary lives and scientific practices.
Thus, the scandal of philosophy -if there is any scandal at all -is neither our inability to put forth a compelling proof for the existence of the external world nor the attempt to propose a "proof" in the first place.The scandal is the failure to recognize the context within which the skeptical doubt is raised.