Wittgensteinian Epistemology and Cartesian Skepticism Nicola Claudio Salvatore Abstract In this paper, I present and criticize a number of influential anti-skeptical strategies inspired by Wittgenstein's remarks on 'hinges'. Furthermore, I argue that, following Wittgenstein's analogy between 'hinges' and 'rules of grammar', we should be able to get rid of Cartesian skeptical scenarios as nonsensical, even if apparently intelligible, combinations of signs. Keywords: Wittgenstein, rules of grammar, skepticism 1 The Cartesian Skeptical Paradox The feature of Cartesian style arguments is that we cannot know certain empirical propositions (such as 'Human beings have bodies', or 'There are external objects') as we may be dreaming, hallucinating, deceived by a demon or be "brains in the vat" (BIV), that is, disembodied brains floating in a vat, connected to supercomputers that stimulate us in just the same way that normal brains are stimulated when they perceive things in a normal way.1 Therefore, as we are unable to refute these skeptical hypotheses, we are also unable to know propositions that we would otherwise accept as being true if we could rule out these scenarios. Cartesian arguments are extremely powerful as they rest on the Closure principle for knowledge. According to this principle, knowledge is "closed" under known entailment. Roughly speaking, this principle states that if an agent knows a proposition (e.g., that she has two hands), and competently deduces from this proposition a second proposition (e.g., that having hands entails that she is not a BIV), then she also knows the second proposition (that she is not a BIV). More formally: The "Closure" Principle If S knows that p, and S competently deduces from p that q, Kriterion – Journal of Philosophy, AO, AO(AO): 1–28. http://www.kriterion-journal-of-philosophy.org c© AO The author 2 KRITERION – Journal of Philosophy, AO, AO(AO): 1–28 thereby coming to believe that q on this basis, while retaining her knowledge that p, then S knows that q2. Let's take a skeptical hypothesis, SH, such as the BIV hypothesis mentioned above, and M, an empirical proposition such as "Human beings have bodies" that would entail the falsity of a skeptical hypothesis. We can then state the structure of Cartesian skeptical arguments as follows: (S1) I do not know not-SH (S2) If I do not know not-SH, then I do not know M (SC) I do not know M Considering that we can repeat this argument for each and every one of our empirical knowledge claims, the radical skeptical consequence we can draw from this and similar arguments is that our knowledge is impossible. 2 Wittgenstein on Skepticism; A Minimal Reading A way of dealing with 'Cartesian style' skepticism is to deny the premise S1) of the skeptical argument, thus affirming contra the skeptic that we can know the falsity of the relevant skeptical hypothesis. For instance, in his "A defence of commonsense" ([16], henceforth DCS) and "Proof of the external world" ([17], henceforth PEW), G. E. Moore famously argued that we can have knowledge of the 'commonsense view of the world', that is, of propositions such as, 'Human beings have bodies', 'There are external objects' or 'The earth existed long before my birth' and that this knowledge would offer a direct response against skeptical worries. Wittgenstein wrote the 676 remarks published posthumously as On Certainty ([48], henceforth OC) under the influence of DCS and PEW, and in particular in the context of conversations he had about these papers with his friend and pupil Norman Malcolm3. As I have briefly mentioned supra, according to Moore, it is possible to provide a direct refutation of Cartesian-style skepticism, thus claiming contra the skeptic that we can know the denials of skeptical hypotheses. But, Wittgenstein argues, to say that we simply 'know' Moore's 'obvious truisms' is somewhat misleading, for a number of reasons. Firstly (OC 349, 483), because in order to say 'I know' one should be able, at least in principle, to produce evidence or to offer compelling grounds for his beliefs; but Moore cannot ground his knowledge-claims Nicola Claudio Salvatore: Wittgensteinian Epistemology 3 with evidence or reasons because (OC 245) his grounds aren't stronger than what they are supposed to justify. As Wittgenstein points out, if a piece of evidence has to count as compelling grounds for our belief in a certain proposition then that evidence must be at least as certain the belief itself. This cannot happen in the case of a Moorean 'commonsense certainty' such as 'I have two hands' because, at least in normal circumstances, nothing is more certain than the fact that we have two hands ([34]). As Wittgenstein writes in OC: If a blind man were to ask me "Have you got two hands?" I should not make sure by looking. If I were to have any doubt of it, then I don't know why I should trust my eyes. For why shouldn't I test my eyes by looking to find out whether I see my two hands? What should be tested by what? (OC 125). Imagine, for instance, that one attempted to legitimate one's claim to know that p by using the evidence that one has for p (for example, what one sees, what one has been told about p and so on). Now, if the evidence we adduced to support p was less secure than p itself, then this same evidence would be unable to support p: My having two hands is, in normal circumstances, as certain as anything that I could produce in evidence for it. That is why I am not in a position to take the sight of my hand as evidence for it (OC 250). Moreover, Wittgenstein argues, a knowledge-claim can be challenged by, for instance, the appeal to evidence and reasons; more generally, when we challenge a knowledge claim we can recognize what and if something has gone wrong in the agent's process of knowledge-acquisition. Things are somewhat different in the case of the denials of Moore's 'obvious truisms of the commonsense'; if, for instance, I believe that I am sitting in my room whilst I am not, there are no grounds on which this belief could be explained as a mistake, as an error based on negligence, fatigue or ignorance. On the contrary, a similar 'false belief' would more likely be the result of a sensorial or mental disturbance (OC 526). As MoyalSharrock points out ([18], 74), in fact, for Wittgenstein if someone was holding seriously a denial of Moore's 'truisms' (i.e., she believed she had no body or that both her parents were men) we would not investigate the truth-value of her affirmations, but instead her ability to understand the language she is using or her sanity (OC 155). If Moore's 'commonsense certainties' are still not knowable, argues Wittgenstein, they are immune from rational doubt. This is so (OC 4 KRITERION – Journal of Philosophy, AO, AO(AO): 1–28 310) because doubts must be based on grounds; that is, they have to be internal to a particular practice and must be in some way or another justified. If they aren't, they are constitutively empty. To illustrate this point, Wittgenstein gives the example (OC 310) of a pupil who constantly interrupts a lesson, questioning the existence of material objects or the meaning of words; far from being a legitimate intellectual task, the pupil's doubt will lack any sense and will at most lead to a sort of epistemic paralysis, for she will just be unable to learn the skill or the subject we are trying to teach her (OC 315). Accordingly, as per Wittgenstein, all reasonable doubts presuppose certainty (OC 114-115); that is, the very fact that we usually raise doubts of every sort at the same time shows and implies that we take something for granted. For example, a doubt about the real existence of an historical figure presupposes that we consider certain an 'obvious truism of the commonsense' such as, 'The world existed a long time before my birth'; a doubt about the existence of a planet presupposes the absence of any doubt about the existence of the external world and so on (OC 114-115, 514-515). But if the statements listed by Moore in DCS are not knowable or doubtable, what is their status? With regard to Moore's 'truisms', Wittgenstein introduces a concept that is pivotal to understand his antiskeptical strategy and at the same time extremely elusive: Moore's 'commonsense certainties' are, in his words, 'hinges'. Wittgenstein uses this term on different occasions, as in OC 341-3, where he writes: The question that we raise and our doubts depend on the fact that some propositions are exempt from doubt, are as it were the hinges on which those turn [. . . .] that is to say, it belongs to the logic of our scientific investigations that certain things are in deed not doubted [. . . ] If I want the door to turn, the hinges must stay put. That is to say, 'hinges' are just apparently empirical contingent claims; on closer inspection, they perform a different, more basic role in our epistemic practices. 3 Wright's Unearned Warrant So far, I have just sketched Wittgenstein's anti-skeptical reflections. Given the elusiveness and obscurity of his work, there is no consensus Nicola Claudio Salvatore: Wittgensteinian Epistemology 5 on how we should interpret Wittgenstein's anti-skeptical strategy and especially the concept of 'hinges'. An influential 'Wittgenstein-inspired' anti-skeptical position is Crispin Wright's 'rational entitlement strategy' ([53], [54]), which can be summarized as follows4. On Wright's account, 'hinges' such as, 'There are external objects', 'Human beings have bodies' or 'The world existed long before my birth' are beliefs whose rejection would rationally necessitate extensive reorganisation, or the complete destruction, of what should be considered as empirical evidence and more generally of our epistemic practices. As per Wright, then, each and every one of our ordinary inquiries would then rest on ungrounded presuppositions, 'hinges'; but still, since the warrant to hold Moore's 'obvious truisms' was acquired in an epistemically responsible way, we could not dismiss them simply because they were groundless as this would lead to complete cognitive paralysis ([53], 191). Following this reading of OC, then, Cartesian skepticism can only show that everyday epistemic practices rest on ungrounded presupposition. But a system of thought, purified of all liability to Moore's 'obvious truisms of the commonsense', would not be that of a rational agent; thus, we have a default rational basis, an entitlement, to believe in 'hinges'. In this way, Wright argues, we are able to know the denials of skeptical hypotheses; and if we can have some sort of knowledge of 'hinges' such as 'Human beings have bodies' or 'There are external objects', we are also able to retain confidence in our everyday empirical knowledge claims. A first problem for the entitlement strategy (see [29], [12] and [27]) is that Wright seems to miss a crucial distinction between practical and epistemic rationality. That is, to accept a non-evidentially warranted hinge would be practically rational, as we obviously need to set aside Cartesian skeptical concerns to pursue any kind of inquiry and to achieve cognitive results ([12], 26). But Cartesian skeptical scenarios are not meant to put under discussion the practical rationality of taking for granted Moore's 'obvious truisms of the commonsense'; rather, they are meant to assess the epistemic rationality of trusting our senses when it is impossible to refute a skeptical scenario such as the BIV one. Thus, even if it would be entirely rational to set aside skeptical concerns whenever we wanted to pursue a given epistemic practice, a Cartesian skeptic can nonetheless argue that the fact that we need true beliefs about the world does not make our acceptance of 'hinges' epistemically rational. Moreover, as has been highlighted by Pritchard ([32], [33]), a crucial 6 KRITERION – Journal of Philosophy, AO, AO(AO): 1–28 issue for the entitlement strategy is the very idea of a belief being rationally grounded in something like an entitlement. This is so because to believe a proposition is to believe that proposition to be true; and if this is right, then it is hard to understand how we can have a rational entitlement to take a 'hinge' for granted without having any reason to consider the 'hinge' at issue to be true. Accordingly, if we cannot say, strictly speaking, that we believe in a 'hinge', for we have no reason to consider it true, then we cannot have knowledge of it either; a mere trusting of or acceptance in the hinge at issue will not suffice. And if this is right, then we cannot have knowledge of 'hinges', even if we are 'rationally entitled' to take them to be true. 4 Pritchard on the Structure of Reason Wittgenstein's reflections on the structure of reason have influenced a more recent 'Wittgenstein-inspired' anti-skeptical position, namely Pritchard's 'hinge-commitment' strategy (forthcoming). To understand his proposal, recall the following remarks we have already quoted supra: If you are not certain of any fact, you cannot be certain of the meaning of your words either [. . . ] If you tried to doubt everything you would not get as far as doubting anything. The game of doubting itself presupposes certainty (OC 114115). The question that we raise and our doubts depend on the fact that some propositions are exempt from doubt, are as it were the hinges on which those turn [. . . .] that is to say, it belongs to the logic of our scientific investigations that certain things are in deed not doubted [...] If I want the door to turn, the hinges must stay put (OC 341-3). As per Pritchard, here Wittgenstein would claim that the same logic of our ways of inquiry presupposes that some propositions are excluded from doubt; and this is not irrational or based on a sort of blind faith, but rather belongs to the way rational inquiries are put forward (see OC 342)5. As a door needs hinges in order to turn, any rational evaluation would require prior commitment to an unquestionable hinge/set of 'hinges' in order to be possible at all. A consequence of this thought (forthcoming, 3) is that any form of universal doubt such as the Cartesian skeptical one is constitutively imNicola Claudio Salvatore: Wittgensteinian Epistemology 7 possible6; there is simply no way to pursue an inquiry in which nothing is taken for granted. In other words, the same generality of the Cartesian skeptical challenge is based on a misleading way of representing the essentially local nature of our enquiries. A proponent of Cartesian skepticism looks for a universal, general evaluation of our beliefs; but crucially there is no such thing as a general evaluation of our beliefs, whether positive (anti-skeptical) or negative (skeptical), for all rational evaluation can take place only in the context of 'hinges' which are themselves immune to rational evaluation. An important consequence of Pritchard's proposal is that it will not affect Closure. Each and every one of our epistemic practices rests on 'hinges' that we accept with a certainty that is the expression of what Pritchard calls "über-hinge' commitment': an a-rational commitment toward our most basic belief that, as we mentioned above, is not itself opened to rational evaluation and that importantly is not a belief. To understand this point, just recall Pritchard's criticism of Wright's rational entitlement. As we have seen, Wright argues that it would be entirely rational to claim that we know Moore's 'obvious truisms of the commonsense' whenever we are involved in an epistemic practice which is valuable to us; but Pritchard argues that in order to know a proposition we need reasons to believe that proposition to be true. And as, following Wright, we have no reason to consider 'hinges' true but the fact that we need to take them for granted, then we cannot have knowledge of them either. With these considerations in mind, we can come back to Pritchard's "über-hinge' commitment'. As we have seen, this commitment would express a fundamental a-rational relationship toward our most basic certainties, a commitment without which no knowledge is possible. Crucially, our basic certainties are not subject to rational evaluation: for instance, they cannot be confirmed or disconfirmed by evidence and thus they are non-propositional in character (that is to say, they cannot be either true or false). Accordingly, they are not beliefs at all. This can help us retain both the Closure principle and our confidence in our most basic certainties. Recall the reformulation of the Closure principle we have already encountered supra: The Competent Deduction Principle If S knows that p, and S competently deduces from p that q, thereby coming to believe that q on this basis, while retaining her knowledge that p, then S knows that q . The crucial aspect of this principle to note ([33], 14) is that it involves an 8 KRITERION – Journal of Philosophy, AO, AO(AO): 1–28 agent forming a belief on the basis of the relevant competent deduction; the idea behind Closure is in fact that an agent can came to acquire new knowledge via competent deduction, where this means that the belief in question is based on that deduction. Accordingly, if we could not rule out a skeptical scenario such as the BIV one, we would be unable to know Moore's 'obvious truisms of the commonsense' such as, 'Human beings have bodies' or 'There are external objects' and thus, given Closure, we would be unable to know anything at all. But our most basic certainties are not beliefs; rather, they are the expression of a-rational, non-propositional commitments. Thus, the skeptic is somewhat right in saying that we do not know Moore's 'obvious truisms of the commonsense'; but this will not lead to skeptical conclusions, for our 'hinge commitments' are not beliefs so they cannot be objects of knowledge. Therefore, the skeptical challenge is misguided in the first place. A first concern that can be raised against this proposal goes as follows. Recall that, following Pritchard's account, the skeptical challenge is based on a misleading way of representing the nature of our epistemic inquiries; as there is nothing like the kind of general enquiry put forward by a Cartesian skeptic, we should rule out skeptical worries for they are at odds with the ways in which rational inquiries are put forward. However, a skeptic can surely grant that our everyday enquiries are essentially local in nature and that our ordinary knowledge claims are made within a background of 'hinge-commitments'; but this is just a reflection of what epistemic agents do in normal circumstances, and can at most tell us how our psychology works whenever we are involved in any given epistemic practice. Still, the mere fact that ordinarily we take for granted several 'hinge commitments' does not necessarily exclude as illegitimate the kind of general, theoretical inquiry put forward by a proponent of Cartesian skepticism; for the Cartesian skeptical challenge is first and foremost a philosophical paradox, which cannot be dismissed on the basis of pragmatic reflections about the essentially local nature of our everyday epistemic practices. However, even if we agree with Pritchard that a general evaluation of our beliefs is somewhat impossible and self-refuting there is still another deep concern that the 'hinge commitment strategy' has to face. Recall that following this proposal, all our epistemic practices rest on unsupported commitments. If this approach can help us to block the skeptical challenge it will nonetheless have a cost: under skeptical scrutiny, we will be forced to admit that all our epistemic practices rest on ungrounded Nicola Claudio Salvatore: Wittgensteinian Epistemology 9 presuppositions which are not open to epistemic evaluation of any sort. When skeptical hypotheses are in play, we are then forced to admit that all our knowledge rests on nothing but a-rational presuppositions such as habit, instinct and social or cultural commitments. Accordingly, Pritchard's 'hinge-commitment' strategy leads to a more subtle form of skepticism which undermines the rationality of our ways of inquiry: a conclusion which is no more reassuring than skepticism itself7. 5 Certainty vs Knowledge Another influential account of Wittgenstein's anti-skeptical strategy is Moyal-Sharrock's 'non-epistemic' reading8; in order to understand this proposal, consider the 'obvious truisms of the commonsense' listed by Moore: There exists at present a living human body, which is my body. This body was born at a certain time in the past, and has existed continuously ever since, though not without undergoing changes; it was, for instance, much smaller when it was born, and for some time afterwards, than it is now. Ever since it was born, it has been either in contact with or not far from the surface of the earth; and, at every moment since it was born, there have also existed many other things, having shape and size in three dimensions [. . . ] from which it has been at various distances. . . ([16], 33). What all these statements have in common is that they refer to the empirical world (physical objects, events, interactions) and so they look like empirical propositions. But, argues Moyal-Sharrock, differently from empirical claims they are unquestionable, indubitable and nonhypothetical ([18], 85) statements that cannot be confirmed or falsified by experience; and as Wittgenstein states in his Cambridge Lectures ([50], 16, quoted in [18], 92), 'a statement which no experience will refute' is a 'rule of grammar': [. . . ] The proposition describing this world-picture might be a part of a kind of mythology. And their role is like that of rules of a game (OC 95, my italics). When Moore says he knows such and such, he is really enumerating a lot of empirical propositions which we affirm without special testing; propositions, that is, which have a peculiar logic role in the system of our empirical propositions (OC 136). 10 KRITERION – Journal of Philosophy, AO, AO(AO): 1–28 Despite their differences, then, for Moyal-Sharrock all 'hinges' share a common feature: namely, they are all rules of grammar which underpin our 'language-games'. This is why, she argues, Wittgenstein considers Moore's knowledge claims in both DCS and PEW as misleading if not completely wrong; for differently from empirical beliefs, 'hinges' cannot be known. To clarify this matter, consider the following entry: And now if I were to say "It is my unshakeable conviction that etc", this means in the present case too that I have not consciously arrived at the conviction by following a particular line of thought [my italics], but that it is anchored in all my questions and answers, so anchored that I cannot touch it (OC 103). As per Moyal-Sharrock, this entry highlights the peculiarity of our relationship with 'hinges'. Our taking them for granted is not based on justification or grounds; for instance, "I cannot say that I have good grounds for the opinion that cats do not grow on trees or that I had a father and a mother" (OC 282). That is, we hold these beliefs unreflectively, for they are not the result of any inquiry and they cannot be supported by any kind of evidence. Still, our lack of grounds for holding 'hinges' does not entail the dramatic conclusions of the Cartesian skeptic, for our relationship with Moore's 'commonsense certainties' is based on training, instinct, repeated exposure ([20], 9): that is, hinges are the result of pre-rational, still perfectly legitimate commitments and are the expression of what Moyal-Sharrock ([18], [19], [20], [21]) calls "objective certainty" ([18], 15-17). This is a concept that she sees as constitutively different from knowledge; knowledge-claims, in fact, require grounds and/or justifications, are open to doubt and can be verified or disconfirmed by evidence. On the contrary, our confidence in the hinges "...lie[s] beyond being justified and unjustified; as it were, as something animal." (OC 359). As per Moyal-Sharrock, our relationship with the 'hinges' is not epistemic or rational at all (hence 'non-epistemic reading'); following her notion of objective certainty our confidence in the hinges should be seen as kind of doxastic attitude, both as a disposition and an occurrence ([18], 54-56). Quoting Wittgenstein: It is just like directly taking-hold of something, as I take hold of my towel without having doubts (OC 510). Nicola Claudio Salvatore: Wittgensteinian Epistemology 11 And yet this direct taking-hold corresponds to sureness, not to a knowing (OC 511). On Moyal-Sharrock's reading, these remarks suggest that our 'objective certainty' is "akin to instinctive or automatic behavior: to a direct taking hold or thought-less grasp" ([18], 62). That is to say, this certainty is a disposition of absolute, animal confidence that is not the result of reasoning, observation or research but is rather a basic attitude of unreasoned, unconscious trust that shows itself in our everyday experiences. In other words, our confidence in Moore's 'obvious truisms of the commonsense' such as, 'There are external objects' or 'Human beings have bodies' is not a theoretical or presuppositional certainty but a practical certainty that can express itself only as a way of acting (OC 7, 395); for instance, a 'hinge' such as 'Human beings have bodies' is the disposition of a living creature, which manifests itself in her acting in the certainty of having a body ([18], 67), and manifests itself in her acting embodied (walking, eating, not attempting to walk through walls etc). Following Moyal-Sharrock's account of Wittgenstein's strategy, Cartesian-style skepticism is the result of a Categorial Mistake9. That is, Cartesian skeptical arguments, even if prima facie compelling, rest on a misleading assumption: the skeptic is simply treating 'hinges' as empirical, propositional knowledge-claims while on the contrary they express a pre-theoretical animal certainty, which is not subject to epistemic evaluation of any sort. Due to this categorial mistake, a proponent of Cartesian Skepticism conflates physical and logical possibility ([18], 170). That is to say, skeptical scenarios such as the BIV one are logically possible but just in the sense that they are conceivable; in other words, we can imagine skeptical scenarios, then run our skeptical arguments and thus conclude that our knowledge is impossible. Still, skeptical hypotheses are nothing but fictional scenarios and once we conflate the logical possibility with the human possibility of being a BIV, then we are making a categorial mistake ([18], 170-171). A consequence of this thought is that Cartesian skeptical scenarios depict a fictional possibility, not a human one; thus, the skeptical challenge is neither a sensible nor legitimate doubt but rather an 'idle mouthing of words' ([18], 174). The mere hypothesis that we might be disembodied brains in the vat has no strength against the objective certainty of 'hinges' such as, 'There are external objects' or 'Human beings have bodies', just as merely thinking that 'human beings can fly unaided' has no strength against the fact that human beings cannot fly without 12 KRITERION – Journal of Philosophy, AO, AO(AO): 1–28 help. Therefore, skeptical beliefs such as 'I might be a disembodied BIV' or 'I might be the victim of an Evil Deceiver' are nothing but beliefbehaviour ([18], 176) and the conclusion we can draw from them, namely that our knowledge is impossible, should be regarded as fiction and not as a possibility: There are contexts then, for the most part: fictional contexts, where the doppelgänger of a universal hinge constitutes a falsifiable proposition. But the negation of a fictional proposition does not entail the negation of any of its doppelgänger. 'I do not know whether I am a human being' pronounced in ordinary circumstances is nonsense. It is not nonsense when pronounced in a fictional context. The problem is that philosophers illegitimately transfer the meaningfulness inherent in the fictional situation to real -life situations ([18], 170, my italics). Following the 'non-epistemic reading', then, Wittgenstein would dismiss Cartesian-style skepticism as the result of a categorial mistake, based on a confusion between imagined and human/logical possibility. Differently from Wright then, according to Moyal-Sharrock, hinge certainties such as, 'There are external objects' and 'Human beings have bodies' are conceptually, rather than practically, indubitable ([18], 161), whereas the empirical doppelganger of a hinge (i.e. a sentence made up of the same words as a hinge, but which does not function as a hinge) can be doubted. So in ordinary and philosophical contexts 'hinges' can't be doubted; but the same sentence used as an empirical proposition in a sci-fi novel can be. Accordingly, as long as we take skeptical hypotheses as fictional scenarios they make sense but their apparent intelligibility is conflated with human possibility. For instance, the BIV hypothesis is a scenario but is just a fictional one that cannot be applied to 'our human form of life'; in the world as we know it we cannot even sensibly conceive the existence of bodiless brains connected to supercomputers, or the existence of Evil Deceivers that systematically deceive us and so forth ([18],178). Thus, the strength of Cartesian-style skepticism is, so to speak, only apparent; and once we take skeptical hypotheses as mere 'philosophical fiction', we should simply dismiss skeptical worries, for a fictional scenario such as the BIV one does not and cannot have any consequences whatsoever on our epistemic practices or, more generally, on our 'human form of life'. Nicola Claudio Salvatore: Wittgensteinian Epistemology 13 This part of the 'non-epistemic reading' seems weak for a number of reasons. If, from one side, Moyal-Sharrock stresses the conceptual, logical indubitability of Moore's 'truisms', she nonetheless seems to grant that the certainty of 'hinges' stems from their function in a given context, to the extent that they can be sensibly questioned and doubted in fictional scenarios where they can 'play the role' of empirical propositions. But crucially, if 'hinges' are 'objectively certainty' because of their role in our ordinary life, a skeptic can still argue that in the context of philosophical inquiry Moore's 'commonsense certainties' play a role which, similar to the role they play in fictional scenarios, is both at odds with our 'human form of life' and still meaningful and legitimate. Moreover, despite Moyal-Sharrock's insistence on the conceptual, logical indubitability of Moore's 'truisms of the commonsense', her rendering of Wittgenstein's strategy seems to resemble Wright's proposal ([39],45), thus incurring the objections I have already raised against this reading. As I have argued throughout this work, to simply state that Cartesian skepticism has no consequence on our 'human form of life' sounds like too much of a pragmatist response against the skeptical challenge. This is so because a skeptic can well agree that skeptical hypotheses have no consequence on our everyday practices or that they are just fictional scenarios; also, she can surely grant that Cartesian-style arguments cannot undermine the pre-rational confidence with which we ordinarily take for granted Moore's 'obvious truisms of the commonsense'. But crucially, and as Wittgenstein was well aware, a skeptic can always argue that she is not concerned with practical doubt (OC 19) but with a, so to speak, purely philosophical one. Also and more importantly, even if we agree with Moyal-Sharrock on the 'nonsensical' nature of skeptical doubts, this nonetheless has no strength against Cartesian style skepticism. Recall the feature of Cartesian skeptical arguments: take a skeptical hypothesis SH such as the BIV one and M, a mundane proposition such as, 'This is a hand'. Now, given the Closure principle, the argument goes as follows: (S1) I do not know not-SH (S2) If I do not know not-SH, then I do not know M Therefore (SC) I do not know M In this argument, whether an agent is seriously doubting if she has a body or not is completely irrelevant to the skeptical conclusion 'I do 14 KRITERION – Journal of Philosophy, AO, AO(AO): 1–28 not know M'. Also, a proponent of Cartesian-style skepticism can surely grant that we are not BIV, or that we are not constantly deceived by an Evil Genius and so on. Still, the main issue is that we cannot know whether we are victim of a skeptical scenario or not; thus, given Closure, we are unable to know anything at all. Moyal-Sharrock does not explicitly discuss this issue, but her 'nonepistemic' reading so construed seems to leave us with two options, neither of which is particularly appealing. If we stress the 'non-epistemic' nature of 'hinges' while claiming that Cartesian skeptical hypotheses have no strength whatsoever against our knowledge claims, we will be forced to reject a very intuitive principle such as Closure.10 If, on the other hand, we do not want to reject Closure, it is hard to see how the 'non-epistemic' reading can help us to solve the skeptical problem. For the conclusion we can draw from this proposal is that Cartesian skepticism is unlivable and at odds with our everyday experience; but still, given Closure and the fact that we cannot know the denials of skeptical scenarios, it is impossible to escape skeptical conclusions. Even if more promising than the other 'OC inspired' anti-skeptical proposals I have considered so far, it seems that, nonetheless, the 'nonepistemic reading' cannot represent a satisfactory anti-skeptical strategy. Nevertheless, there are many promising insights we can draw from Moyal-Sharrock's interpretation of Wittgenstein's thought and especially from the analogy between 'hinges' and 'rules of grammar', which I will consider in the next section. 6 Hinges and Rules of Grammar Very generally, in the second phase of his thought, Wittgenstein calls rules of grammar 'the conditions, the method necessary for comparing a proposition with reality' ([49], 88). Thus, for Wittgenstein, everything that determines the sense of an expression belongs to its 'grammar', which also specifies the licit combinatorial possibilities of an expression (for instance, which combinations make sense and which don't, which are allowed and which are not allowed', cfr. [13], 146). To understand this point, consider the following statements: i) What is red must be colored ii) Nothing can be red and green all over Nicola Claudio Salvatore: Wittgensteinian Epistemology 15 iii) All bachelors are unmarried iv) A proposition is either true or false v) 12 x 12 = 144 Despite their differences, all these share a number of significant common features. Firstly, they are all normative as they delimit what it makes sense to say, for instance, licensing and prohibiting inferences. Just consider i): if p is called red is correctly characterised as 'colored', to say that it is red and to deny that it is colored would be a misuse of language, that is, a move excluded from a language-game. Similarly ii), even if it looks as if it is a description of the physics of color, is in fact a rule that we use to exclude the description of an object as being red and green all over. iii) looks like a true statement of fact about bachelors but is, rather, meant to explain the meaning of the word 'bachelor'. iv) looks like a description, a generalization about propositions in the same way that the statement 'All lions are carnivorous' is a generalization about lions. However, things are somewhat different, for we use iv) to define what may be correctly called 'a proposition' in logical reasoning; also, it does not exclude a third possibility but rather excludes as meaningless the phrase 'a proposition which is neither true nor false'11. Finally12, central to Wittgenstein's philosophy of mathematics is the view that mathematically necessary truths are not descriptive but normative; for instance, v) licenses and prohibits inferences, in the sense that it licenses transformations of empirical statements and at the same time excludes other inferences as invalid. Following v)13, we can legitimately transform the statement: 'There were 12 books each on 12 shelves in the bookshop' into: 'There were 144 books in the bookshop'; also, v) excludes as illegitimate, 'There were 12 books each on 12 shelves, so there were 1212 books in the bookshop' (an inference which is also excluded by the true inequation 12× 12 6= 1212). A second feature of Wittgenstein's 'rules of grammar' is that they cannot be confirmed or disconfirmed by reality; rather, they determine what counts as a possible description of reality. That is to say, statements like i) and ii) cannot be confirmed by empirical evidence, but are, rather, presupposed by any 'language game' with color words; also, these grammatical rules cannot possibly be disconfirmed by reality, say by the existence of a 'colorless red object' or of 'something that is red and green all over'. Likewise, we could not verify iii) by, for instance, investigating the marital status of people identified as bachelors, and no 'married bachelor' could possibly disconfirm iii). 16 KRITERION – Journal of Philosophy, AO, AO(AO): 1–28 Similarly, even if we do perfectly well speak of half-truths, or rough or approximate truths or of something being partly true or partly false, this does not affect iv) in any way, for the objects of such assertions are not cut to the pattern required for logical inference and thus cannot be considered propositions; therefore, these assertions cannot confirm or disconfirm iv) ([13], 265). Finally, even if we could imagine a different arithmetic in which v) could turn out to be wrong and v*) 12 x 12 = 1212 was correct, this would not disconfirm v), for this v*) would simply not belong to the practice we call 'arithmetic'. A third and important feature of Wittgenstein's 'rules of grammar' is that they are not propositions; namely, they cannot be either true or false for their 'negation' is not false but senseless. Just consider the following sentences: i*) p is red and is not colored ii*) p is red and green all over iii*) Some bachelors are married iv*) a proposition is neither true nor false v*) 12 x 12 = 1212 All these are nothing but nonsensical, even if intelligible, combinations of signs14. If this is obvious for the putative statements from i*) to iv*), then, as per Wittgenstein, even an 'equation' such as v*) is senseless rather than simply false. As he argued in one of his lectures: The application of a mathematical sentence occurring in our language is not to show us what is true or false but what is sense and what is nonsense. This holds for all mathematicsarithmetic, geometry, etc. For example, there are mathematical propositions about ellipses which show that 'I cut the elliptical cake in 8 equal parts' does not make sense. And there are mathematical propositions about circles which show that it does make sense to say "I cut the circular cake in 8 equal parts'. The terms 'sense' and 'nonsense', rather than the terms 'true' and 'false', bring out the relation of mathematical propositions to non-mathematical propositions (AWL 152)15. Thus, the difference between 'rules of grammar' and their negations is not similar to the difference between true and false statements, but to the Nicola Claudio Salvatore: Wittgensteinian Epistemology 17 difference between a rule of expression and a use of words or symbols which that rule excludes as nonsensical. 7 Hinges and the Boundaries of Rational Agency To sum up, Wittgenstein's 'rules of grammar' have three features which make them different from empirical beliefs. Firstly, they are not descriptive but normative; secondly, they cannot be confirmed or disconfirmed by reality but, rather, are ways to make sense of reality ; finally, they are not propositions as their negations are not false but senseless. With these points in mind, consider the following passages of OC, in which Wittgenstein explicitly compares Moore's 'obvious truisms' to mathematical truths: "So is the hypothesis possible, that all the things around us don't exist? Would that not be like the hypothesis of our having miscalculated in all our calculations? (OC 55) I cannot be making a mistake about 12x12 being 144. And now one cannot contrast mathematical certainty with the relative uncertainty of empirical propositions. For the mathematical proposition has been obtained by a series of actions that are in no way different from the actions of the rest of our lives, and are in the same degree liable to forgetfulness, oversight and illusion [. . . ] The mathematical proposition has, as it were officially, been given the stamp of incontestability. I.e.: "Dispute about other things; this is immovable it is a hinge on which your dispute can turn" (OC 651-655, my italics). If mathematical truths, qua rules of grammar, license possible ways to describe reality, then to deny or doubt a rule such as v) 12x12=144 does not display factual ignorance but rather the inability to competently engage in the language game called 'arithmetic'. As I have already mentioned throughout this work, for Wittgenstein, 'the game of doubting itself presupposes certainty' (OC 115), that is that something is taken for granted, at least the meaning of words (OC 676). Accordingly, the skeptic's never-ending doubt will deprive her words of their meaning and will, at most, show her inability to engage in the ordinary 'language-game' of asking meaningful questions, as to deny or doubt that i) What is red must be colored and ii) Nothing can be red and 18 KRITERION – Journal of Philosophy, AO, AO(AO): 1–28 green all over will display an agent's inability to engage in any sensible language game with color words. This part of Wittgenstein's proposal could be said to resemble Wright's rational entitlement strategy and it incurs similar problems. Recall that, following Wright, we are rationally entitled to take for granted 'hinges' such as 'Human beings have bodies' or 'There are external objects', for to dismiss them will end up with the impossibility of pursuing any inquiry at all; as practical rational agency is a basic way for us to act, it would be rational to say that we knew 'hinges', even if in an unwarranted way. As we have extensively seen supra, even if to take 'hinges' for granted would be practically rational, for not to do so would lead to a cognitive paralysis, a skeptic could nonetheless argue that the very fact that we need to act as if 'hinges' are true does not make this acceptance epistemically rational. But following Wittgenstein's reflection on the normative nature of 'hinges', not to doubt or deny Moore's 'obvious truisms' is not something that we do merely out of practical considerations as in Wright's proposal; rather, it is a constitutive part of 'the essence of the language-game' called 'epistemic inquiry' (OC 370): I want to say: propositions of the form of empirical propositions, and not only propositions of logic, form the foundation of all operating with thoughts (with language) [. . . ] If I say "we assume that the earth has existed for many years past" (or something similar), then of course it sounds strange that we should assume such a thing. But in the entire system of our language-games it belongs to the foundations. The assumption, one might say, forms the basis of action, and therefore, naturally, of thought (OC 401-411, my italics). As per Wittgenstein, 'hinges' such as 'There are external objects' and 'Human beings have bodies' play a basic, foundational role in our system of beliefs, and to take them for granted belongs to our method of doubt and enquiry (OC 151). In other words, even if they resemble empirical propositions or their origin is empirical, within our practices they are used as rules which enable us to make sense of reality, thus drawing a line between sense and nonsense rather than between truth and falsity. Thus, to doubt or deny Moore's 'obvious truisms of the commonsense' would not only go against our practical rationality, but more crucially would also undermine the very notion of 'rational enquiry'. Nicola Claudio Salvatore: Wittgensteinian Epistemology 19 8 Wittgensteinian Epistemology and Cartesian Skepticism As we have seen, then, for Wittgenstein, Moore's 'commonsense certainties' are a condition of possibility of any meaningful inquiry; as he puts the matter, 'about certain empirical propositions no doubt can exist if making judgments is to be possible at all' (OC 308, my italics). A thought which is stressed in a number of remarks of OC, where Wittgenstein defines 'hinges' as 'the scaffolding of our thoughts' (OC 211), 'foundation-walls' (OC 248), the 'substratum of all our enquiring and asserting' (OC 162), 'the foundation of all operating with thoughts' (401) and 'fundamental principles of human enquiry' (OC 670). To understand a first promising anti-skeptical consequence of this account, recall the putative 'negation' of the rules of grammar we have encountered supra: i*) p is red and is not colored ii*) p is red and green all over iii*) Some bachelors are married iv*) a proposition is neither true nor false v*) 12× 12 = 1212 As we have already seen above, Wittgenstein's rules of grammar are non-propositional in character, thus they cannot be either true or false; accordingly, their 'negation' is not false but senseless, that is, an illicit combination of signs. In a similar fashion, as 'hinges' such as 'Human beings have bodies' or 'There are external objects' are not propositional, for they have a normative rather than a descriptive role, then their putative 'negation' should be dismissed as an illicit (and not only fictional as in MoyalSharrock's proposal) combination of signs which is excluded from the practice called 'rational epistemic inquiry', as the putative statement v*) 12 × 12 = 1212 is a move excluded from the language-game called 'arithmetic'. To understand a promising anti-skeptical implication of this point, recall the feature of Cartesian-style arguments: (S1) I do not know not-SH (S2) If I do not know not-SH, then I do not know M 20 KRITERION – Journal of Philosophy, AO, AO(AO): 1–28 (SC) I do not know M where not-SH can be a 'hinge' such as 'Human beings have bodies' or 'There are external objects'. This argument seems compelling as long as we take 'hinges' as propositional beliefs which can be either confirmed by evidence or legitimately doubted once we run skeptical arguments. But even if they resemble empirical contingent propositions, 'hinges' are nonpropositional rules of grammar which enable us to make sense of reality. Accordingly, skeptical hypotheses such as 'I might be a disembodied BIV' should not be regarded as sensible philosophical challenges but rather as nonsensical, even if prima facie meaningful, combinations of signs. Another promising consequence of a non-propositional account so construed is that, different from Moyal-Sharrock's reading of OC, it will not affect the Closure principle and at the same time will not lead to skeptical conclusions. Recall that following the non-epistemic reading, 'the certainty of hinges' is a pre-rational, animal commitment which is not subject to epistemic evaluation of any sort. Accordingly, following this account, we will have either to reject Closure or, with this principle still in play, to agree with the skeptic that our knowledge is impossible. Consider the formulation of Closure proposed by Williamson ([44]) and Hawthorne ([14]) which we have encountered throughout this work: The Competent Deduction principle If S knows that p, and S competently deduces from p that q, thereby coming to believe that q on this basis while retaining her knowledge that p, then S knows that q. The idea behind this version of Closure is in fact that an agent can come to acquire new knowledge via competent deduction where this means that the belief in question is based on that deduction. Accordingly, if we cannot rule out a skeptical scenario such as the BIV one, given Closure we would still be unable to know anything at all. The non-propositional nature of Wittgenstein's account of 'hinges' can help us to positively address this issue. As we have seen while presenting Pritchard's 'hinge-commitment' strategy, the crucial aspect to note about Closure is that it involves an agent forming a belief on the basis of the relevant competent deduction. But crucially, 'hinges' are not the expressions of a propositional attitude such as a belief in; rather, they are the expression of non-propositional rules.16 Accordingly the negations of 'hinges', that is, skeptical hypotheses such as 'I might be a disembodied BIV' or 'I might be deceived by an Nicola Claudio Salvatore: Wittgensteinian Epistemology 21 Evil Demon' are not beliefs either ; rather, they are just nonsensical combinations of signs, from which no valid inference or deduction (e.g. 'If I do not know not-SH, then I do not know M') can be made. That is to say, if skeptical hypotheses are not propositional beliefs but rather, senseless negations of non propositional rules, then from the fact that we don't know whether we are victims of a skeptical scenario we cannot infer or deduce that we don't know everyday empirical propositions ; we are thus in a position to retain Closure (which can be applied only to propositional beliefs, and not to nonsensical negations of non propositional rules) and our confidence in our everyday knowledge claims. 9 Concluding Remarks In this paper, I have argued that following the analogy between 'hinges' and rules of grammar, we should be able to get rid of skeptical hypotheses. This is so because given the non propositional, normative nature of 'hinges' such as ' There are external objects' or 'Human beings have bodies' their skeptical negations are not propositional beliefs but rather, nonsensical, even if apparently meaningful, combinations of signs from which no valid inference or deduction can be made17. Notes 1 See [35]. 2 This is essentially the formulation of the Closure principle defended by [44], 117, and [14], 29. 3 While writing OC Wittgenstein was also heavily influenced by Henry Newman's lectures on religious beliefs (see [24], [25]). For a more detailed analysis of the relationship between Newman's and Wittgenstein's anti-skeptical strategies, see [28]. 4 Wright's proposal is informed by his diagnosis of Moore's Proof ([52]), from which has originated a huge debate that would be impossible to summarize here. For a critical analysis of Wright's treatment of PEW see [36], [37], [38], [7] and [2], [3]. 5 Cfr OC 342: [. . . ] it belongs to the logic of our scientific investigations that certain things are indeed not doubted. 6 See OC 450: "A doubt that doubted everything would not be a doubt". 7 Pritchard has explicitly addressed this issue, stating that even if his proposal blocked the skeptical challenge it would nonetheless lead to what he names 'epistemic angst' or, more recently, 'epistemic vertigo'. See [31]. Moreover, it should be noted that Pritchard's reflections on 'hinges' are only a part of a more complex anti-skeptical framework.; the other part is called epistemological disjunctivism ([34]) . As in this work I am focusing only on 'Wittgenstein inspired' 22 KRITERION – Journal of Philosophy, AO, AO(AO): 1–28 anti-skeptical proposals, to present and discuss the merits of Pritchard's epistemological disjunctivism would go beyond the scope of this essay and is thus not a task I shall set myself here. 8 It is worth noting that Pritchard ([30]) calls his own anti skeptical strategy nonepistemic (268) and defines Moyal Sharrock's proposal 'non-propositional '(265). Still, Moyal Sharrock stresses the non epistemic, pre rational nature of 'hinges' while as we have seen above Pritchard focuses on the non propositional nature of what he names 'uber hinge commitments'; hence I preferred to call the former strategy 'non epistemic'. 9 See OC 308: 'Knowledge' and 'Certainty' belong to different categories. They are not two 'mental states' like; say 'surmising' and 'being sure'. (Here, I assume that it is meaningful for me to say, "I know what (e.g.) the word "doubt" means and that this sentence indicates that the word "doubt" has a logical role.) What interests us now is not being sure but knowledge. That is, we are interested in the fact that about certain empirical propositions no doubt can exist if making judgments is to be possible at all. Or again: I am inclined to believe that not everything that has the form of an empirical proposition is one. 10 This line has been most notably proposed by [8], [9], [10], [11]) and [26]. 11 According to the proponents of 'many-valued logic' such as [43], statements of the form 'a proposition which is neither true nor false' are 'borderline cases', whose truth value lies between 0 (full falsehood) and 1(full truth); thus, they would not be mere senseless combinations of signs as in Wittgenstein's account. Even though this approach has been extremely useful to deal with a number of philosophical issues such as 'the vagueness problems', this view is still far from uncontroversial and has originated a huge debate that would be impossible to summarize here. For an up to date discussion on multi-valued logic and the 'vagueness problem', see [42]. 12 In the following, I will just sketch some uncontroversial aspects of Wittgenstein's philosophy of mathematics, in order to cast more light on his conception of 'rules of grammar'. A detailed reconstruction of Wittgenstein's views on the matter and of the debate they originated would fall beyond the scope of this work. 13 This is a slightly modified example used by [13], 269. 14 It is worth noting that Wittgenstein considers 'senseless' every combination of signs excluded from a 'rule of grammar'. This is so because as grammatical rules are ways to make sense of reality, their correctness is antecedent to questions of truth of falsity and so they lack a truth-value. Accordingly, their putative negations lack truth-value as well; thus, they cannot be considered strictly speaking false but senseless, that is illicit, combinations of signs. 15 It could be argued that there are mathematical and geometrical discoveries, as in the case of 'Non-Euclidean' geometry. Still, as per Wittgenstein, these are different from empirical discoveries for they do not tell us anything about reality but are, rather, different techniques to describe reality. See infra. 16 For a similar account of 'hinges' and their anti skeptical significance, see [4], [5] . Roughly, as per Coliva 'hinges', even if propositional, have a normative role, and their acceptance is a 'condition of possibility' of any rational enquiry. A first difference between this account and the one I'm defending here goes as follows; according to Coliva, hinges are propositional (albeit non –bipolar) ; on the contrary, I claim that they are non propositional, hence their putative 'negations' (such Nicola Claudio Salvatore: Wittgensteinian Epistemology 23 as skeptical hypotheses)are senseless and excluded from our epistemic practices. Moreover, and more importantly, Coliva proposes a limitation of the Closure principle ([5], 86; a similar view is defended in [1]), which stems from her views on warrant and epistemic justification that will be impossible to summarize here. However, following my account of hinges there is no need to defend a limitation of Closure; this is because if skeptical hypotheses SH such as 'I might be a BIV' or ' I might be deceived by an Evil Deceiver' are senseless combinations of signs, so are their putative 'negations ' not-SH; then from the fact that we don't know whether we are victims of a skeptical scenario ('I do not know not-SH' where both SH and its 'negation' are illicit combination of signs )we cannot infer or deduce that we do not know our everyday propositions M even with a 'strong' version of Closure in play. On Coliva's reading of OC and its anti-skeptical implications, see [21] and [31]. 17 For a general introduction to OC see also [23] and [41]. Other influential 'OC inspired' anti-skeptical strategies are [6] and [45], [46], [47]. For a critical evaluation of Conant's and Williams' proposals, see [39], [40]. 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