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1 DESCARTES, HYPERBOLIC DOUBT, AND THE APPEAL TO GOD If you found yourself in such a state, you would be sure that all your rational beliefs were unsubstantial fancies. (13) S ECTION 1: M ETHODOLOGICAL D OUBTS In the first lecture, we saw how the Pyrrhonian sceptic starts as a zetetikos, an inquirer after truth. His motivation is to seek the truth and nature of things and he fails, finding instead puzzlement (aporia). While from his starting position this would seem to be a disastrous result, the resulting suspension of belief (epoche) ‘fortuitously’ results in tranquillity (ataraxia). Clearly, if one attains this tranquillity, as Montaigne seemed to have done, then that is a good result. But for one who is still motivated to find the truth, it looks like giving up on the project of inquiry, an overcoming of one’s natural desires as a zetetikos. So the question becomes: how do we take seriously the problems raised by the sceptic while not giving up on our search for truth? The key philosophical idea here seems to have been first articulated by the Persian Islamic philosopher Al-‐ Ghazali in 1105. The first step Al-‐Ghazali makes is to ask what it is the zetetikos/enquirer is seeking: So I began by saying to myself: “What I seek is knowledge of the true meaning of things. Of necessity, therefore, I must inquire into just what the true meaning of knowledge is.” (Deliverance from Error, 7) Al-‐Ghazali quickly concludes that the knowledge he seeks must be sure and certain and safe from error (8). But that leads him directly to a process of self-‐ inspection: he must examine everything he takes himself to know and ask if it meets these conditions, rejecting it if it does not. He rapidly comes to the conclusion that the only cognitions which appear to be safe from error are ‘sense-‐data and the self-‐evident truths’ (9). But he uses standard concerns about the senses to undermine the safety of perceptual knowledge (it is worth noting that his examples don’t come from Sextus – this could be because he hadn’t read the Outlines or because he wanted to draw upon a specifically Islamic tradition at this point), and the possibility of a state which stands to our waking state as our waking does to our dreaming1 to undermine the reliability of reason: He is left in a forlorn state of unhappy scepticism without the fortuitous ataraxia of the Pyrrhonist. Al-‐ Ghazali himself eventually finds his tranquillity through religious mysticism, specifically Sufism, and rejecting the possibility of philosophy. So his final position is not that different from the sceptical fideists, but his route is different, for the scepticism he achieves is both unsettling and only a stepping stone, later to be rejected. This difference comes from the different ‘choreography’ of the sceptical arguments. The Pyrrhonist does not argue against appearances but offers opposing accounts. His objective is not to get you to change your mind about how things seem to you, but to accept that they may seem different to others (or yourself at different times) and there is no saying who is right. In contrast, Al-‐Ghazali is using the sceptical arguments to persuade you to reject the appearances, to give up, to reject, what you previously accepted.2 This difference derives from the methodological starting point: we should only continue accepting what we cannot cast doubt upon, what is certain and safe. With that starting point, the sceptical arguments take on a completely different character. This was also Descartes’ starting point five hundred years later. He went so far as to frame the method as requiring us to disbelieve the indubitable (Principles 1.2). However, he did not go on to reject philosophy like Al-‐Ghazali, but to use this methodological doubt to provide a secure foundation for metaphysics and the sciences. From his perspective, both Pyrrhonism and Al-‐Ghazali’s mysticism would be failures, not the happy results their proponents took them to be. Descartes describes his motivations as: transitivity of identity (‘Pyrrho’, Remark B, p.199) took the early modern application of scepticism beyond his predecessors, but he didn’t use dreaming but the ‘opposing account’ of revealed religion to achieve this. I have deliberately skirted over the controversial issue of whether the Pyrrhonian sceptic has beliefs or just some weaker attitude of acceptance, which would need to be settled for a precise statement of the difference here noted. 2 As we will see, this use of dreaming is rather different to Descartes’ and is perhaps closer to Zhuangzi. Bayle’s application of scepticism to self-‐evident truths such as the 1 Contact: tom.stoneham@york.ac.uk / @tomstoneham 2 I realized that it was necessary, once in the course of my life, to demolish everything completely and start again from the right foundations if I wanted to establish anything at all in the sciences that was stable and likely to last. (Meditations I; AT VIII 17)3 And the method he uses to identify the ‘right foundations’ is Al-‐Ghazali’s: Reason now leads me to think that I should hold back my assent from opinions which are not completely certain and indubitable just as carefully as I do from those which are patently false (18). To identify those which are not certain, Descartes goes through a sequence of modes of generating doubt. First, he notes the possibility of perceptual error, but thinks we can identify cases where the senses are functioning properly – according to their telos – and thus error only occurs in abnormal situations (this was a common Aristotelian response to Pyrrhonist arguments about the senses). Then, via consideration of madness, he comes to dreaming. Unlike Al-‐Ghazali’s suggestion that there is a possible state of super-‐wakefulness with respect to which our ordinary wakefulness will seem as out of touch with reality as dreaming does to us, Descartes notes that dreams can include quite ordinary experiences, so there is a question of whether I am now dreaming or not: I see plainly that there are never any sure signs by means of which being awake can be distinguished from being asleep. (19) There has been much ink split over how exactly this argument is meant to work, but the most plausible reconstruction goes like this (e.g. Stroud 1984, ch.1): “If I am to know that I am now sitting at my desk writing, then I must know I am not now dreaming that I am sitting at my desk writing. But any criterion or test for not dreaming, for being awake, is one I could dream that I have passed. So it is impossible to know I am not now dreaming and thus impossible to know I am now sitting at my desk writing.” It is often thought that this argument turns upon phenomenological indistinguishability: any waking experience is phenomenologically indistinguishable from some possible dream experience. If so, it would involve claims about dreams which go beyond All further references to Descartes will be from the Meditations, using the Adam & Tannery volume VII page numbers. 3 anything Al-‐Ghazali or Sextus were committed to.4 However, this is unnecessary. What is essential to the argument is that whatever I claim to be a sign that I am now awake is something which I could be ‘tricked’ into thinking while asleep. The trick doesn’t have to rely on phenomenological indistinguishability, only on the cognitive differences between wakefulness and sleep. When Descartes returns to the dreaming argument in the 6th Meditation, he observes that wakefulness has features which dreams lack: “dreams are never linked by memory with all the other actions of life as waking experiences are” (89). Critics have noted that when we are dreaming we could be ‘tricked’ into thinking that our current experiences are linked to the rest of our lives by memory, so this gives no response at all to the dreaming argument. But that misses the subtlety of the move. Descartes is not saying that there is a way to tell that one is dreaming, but a way to tell that one is awake. By this stage he has defended a criterion of truth, namely clear and distinct perception, and he is saying that when awake we can, by this criterion, know that we are awake. When we are asleep we cannot know anything because we can have no clear and distinct perceptions, but when we are awake we can have clear and distinct perceptions and can thus know things. One of the things we can know in this way when awake is that we are awake. So while Descartes leaves the dreaming argument in Meditation I as if it is effective against knowledge of particulars, once he has a criterion of truth that can only be applied in wakeful states, it turns out to be not effective at all.5 Which is, in part, why he goes on to the next layer of doubt-‐inducing sceptical arguments. Interestingly, he first tries to argue by opposed accounts. Noting that I cannot bring myself to doubt ‘transparent truths’ such as 2+3=5 and a square has four sides, even if I cannot rule out that I am dreaming, he considers two accounts of how I might have come by this indubitability. The first is that there is a good, omnipotent God who has created me, and on this account my certainty would be justified. The second is that: Claims about dreams I take to be utterly unsubstantiated but lazily accepted as ‘obvious’ by contemporary philosophers. 4 The skeptical argument Descartes is here ignoring is Sextus’ Problem of the Criterion, because he thinks it is impossible to cast doubt on what we clearly and distinctly perceive. But that overlooks the vicious circularity/regress objection. 5 Contact: tom.stoneham@york.ac.uk / @tomstoneham 3 I have arrived at my present state by fate or chance or a continuous chain of events, or by some other means. (21) If I am not created by a good God but have my origin in one of these other sources, then there is no reason to think subjective indubitability is a mark of genuine truth. Descartes notes that he cannot answer these arguments, but also notes that – as we saw with Pyrrhonism – this way of arguing doesn’t undermine the appearances: I shall never get out of the habit of confidently assenting to these appearances. (22) The route of opposing accounts does not have the methodological power he needs, the power to get us to reject all we previously believed.6 So he introduces his final mode, the “malicious demon of utmost power and cunning [who] has employed all his energies in order to deceive me”. In the 20th century, the powerful, cunning demon is replaced by a different image of manipulation: the evil scientist who feeds messages to a brain in a vat (or the aliens of the Matrix). But the point is the same, namely to induce the hyperbolic doubt which leads us to ‘reject the appearances’, to no longer accept what we previously believed. S ECTION 2: H YPERBOLIC D OUBTS Dreaming is a state in which the faculty of reason doesn’t function properly, so when we are dreaming, we do not acquire knowledge. But precisely because of this, it was shown not to undermine our ability to acquire knowledge when waking, when the faculty of reason does function properly. The evil demon is different. The idea here is that for any range of propositions I claim to know, such as those which are about or entail the existence of an external world, there is some hypothesis, some possible scenario, in which my reason functions just as well and in which I have all the same beliefs and experiences, and yet those propositions are false. Call such a sceptical scenario H and a proposition which it renders false P. Then we can see the form of the argument is very simple: 1. 2. 3. If K(P) then K(~H) ~K(~H) ~K(P) In the Principles, Descartes unfortunately moves straight to the hyperbolic doubt without the evil demon, which is why I am concentrating on the presentation in the Meditations. 6 The scenario H just has to be one in which P is false (so knowing P would rule it out) and one I cannot know I am not in. While an evil demon might be able to make even the proposition that there is an external world false, an evil scientist who is presumably part of the external world can make everything I believe about the character of the external world false – this is the situation in the film The Matrix. Either way, the argument is very powerful indeed, ruling out knowledge of pretty much every contingent proposition. One assumption in the argument, of course, is that one’s beliefs are only contingently related to the contingent truths, so we it is possible for the contingent truths to be different without changing the beliefs we have, and that might be, and has been, questioned (e.g. McCulloch). However, for present purposes it is more important to note that the argument only really works on contingent truths. For in order to be convinced of the premises, I have to be able to conceive of H. But I cannot conceive of a scenario in which the necessary truths, or at least the a priori necessary truths, are false, so I cannot conceive of an H in which the two premises are true for a necessary proposition, P.7 What I can conceive is a scenario in which I am wrong in my beliefs about the necessary truths – after all that happens every time I make an arithmetical error – but such scenarios do not get to the conclusion Descartes wants. Either I have gone wrong because I am in a cognitively disabling state like dreaming or because I have made an error which I could in theory correct. The power of the evil demon comes from the fact that the falsity of my belief has nothing to do with me or how I have reached it or what evidence or learning I have: it is achieved directly by the manipulation of the world about which I am believing. S ECTION 3: E SCAPE Descartes’s problem now is that the evil demon rules out all knowledge of contingent truths but necessary truths do not seem sufficient as a foundation for the sciences, other than “arithmetic, geometry and other subjects of this kind, which deal only with the simplest and most general things, regardless of whether they really exist in nature or not” (20; cf. Berkeley DHP1 173). Furthermore, the quasi-‐Pyrrhonist arguments The situation is rather more complex for the historical Descartes because he believed that God’s omnipotence meant he could have made 2+2=5, so there is an H in which my beliefs about necessary propositions are rendered false without my going wrong in any way. But the assumptions needed to get to this position may not be available to one promoting a sceptical argument, so we can’t grant the evil demon that much power. 7 Contact: tom.stoneham@york.ac.uk / @tomstoneham 4 leave me wondering whether my subjective certainty in these matters, despite being unshakeable, is sufficient for truth: perhaps I am just ill-‐equipped to judge. This is the ‘gripping’ (McDowell) situation that Descartes’ highly literary first-‐person narrative leaves us in. But for him it is all just a tool, an instrument to get us quickly on to the project of constructing a basis for scientific knowledge, as the shockingly rapid (for those of us who are, unlike Descartes, gripped by the skeptical arguments) slide through the arguments at the beginning of Part 1 of the planned four part Principles of Philosophy reveals. Descartes is not impressed by the skeptical arguments because he is convinced he has a way out of all skeptical problems. But we shall see that he is left in a position which doesn’t really solve the problem he has created. His way out of the sceptical aporia involves three stages: 1. 2. 3. Establish a range of contingent truths which are immune to the evil demon argument. Use these plus the subjectively certain clear and distinct necessary truths to prove the existence of a benign God. Show that such a God rules out all the evil demon hypotheses and also guarantees that our clear and distinct perceptions are true. Famously, Descartes’ escape from scepticism starts with the Cogito: I think therefore I am. He notes that whatever the evil demon does, “he will never bring it about that I am nothing so long as I think that I am something” (25). Now, in some formulations, Descartes seems to be drawing an inference: I think therefore I am. In which case the first point which avoided doubt would be the claim that he is thinking. But in the Meditations, it is the conclusion ‘I exist’ which seems to be his first proposition. His argument for this being immune to the sceptical doubts is that if we suppose an evil demon “in that case I too undoubtedly exist, if he is deceiving me”. When Descartes goes on to say that the evil demon will “never bring it about that I am nothing so long as I think that I am something”, he is reiterating the point that the evil demon cannot both deceive me, that is cause me to have false beliefs, and make me not exist, for then I would have no thoughts or beliefs. He is not claiming that the proposition that he is thinking is immune to doubt (or not yet, anyway), but that reflection on the evil demon hypothesis shows that the sceptic cannot bring him to doubt that he exists: that is a contingent proposition which I believe and which no sceptical hypothesis can be inconsistent with. Having established his existence, Descartes goes on to ask about what kind of thing he is, to see if he can know anything about himself which is also immune to the hyperbolic doubts caused by the evil demon. After much exploration of possibilities, he concludes that he is an ‘I’ who: understands some things, who affirms that this one thing is true, denies everything else, desires to know more, is unwilling to be deceived, imagines many things even involuntarily, and is aware of many things which apparently come from the senses? Are not all these things just as true as the fact that I exist, even if I am asleep all the time, and even if he who created me is doing all he can to deceive me? (28-‐9) Here he is clearly claiming that the evil demon argument cannot be applied to our own mental states, but his reasoning is rather less clear than in the case of his existence. Why couldn’t a demon give me all the same beliefs about my mental states, while making those beliefs false? When I believe that I am hungry, or imagining the Shanghai skyline or thinking about Descartes, why couldn’t the evil demon bring it about that, though I believe all these things about myself, none of them are actually true? Descartes never really tells us, but I suspect he thinks that this is a case of clear and distinct perception. That would explain why he both treats his own mind as sceptic-‐proof and allows the possibility of error about one’s beliefs and passions. The way this criterion of truth works is that when I have the clear and distinct perception, I cannot go wrong, but I can form the same belief on another basis, without the clear and distinct perception, and in that case I am highly prone to error. So the claim would be that while my existence is logically immune from the evil demon’s deceit, my mind is immune in the same way as necessary truths. Thus my beliefs about my own mind are prone to the quasi-‐Pyrrhonist opposing accounts objection until we can establish the origin of my faculties. S ECTION 4: T HE A PPEAL TO G OD I won’t spend time here and now analyzing the details of Descartes’ subsequent arguments. Using his knowledge of his mind he identifies an idea of God as infinite, argues that the only possible source of this idea is God and thus that God exists. The existence of God deals with the Pyrrhonist argument from opposing accounts: we now know which story of the origin of my faculty of clear and distinct perception is correct. It also rules out an evil demon: God is no Contact: tom.stoneham@york.ac.uk / @tomstoneham deceiver. So if we use our faculties carefully, we can gain knowledge within the limits of our own finitude. Much scholarly ink has been spilt on the alleged ‘Cartesian Circle’: Descartes has used his clear and distinct perceptions to establish the existence of God, who he then uses to defeat the concern that these are merely subjective certainties which are not necessarily a criterion of truth. I shall not go into this debate in detail because my main concern arises even if we grant Descartes everything, but it is worth noting that the doubts about clear and distinct perception are Pyrrhonian, being based upon opposing accounts, and thus do not undermine appearances. In particular, he is not presenting a sceptical hypothesis on which the things he clearly and distinctly perceives are false. Merely one on which he does not (yet) know them to be true, even though he cannot stop believing them. Critics have also noted that his proof of the existence of God on the basis of his clear and distinct perceptions is not as convincing to others as it is to him. However, even if we grant this argument and thus that Descartes has shown there is a benign God who does not deceive me and who created me in such a way that if I use my faculties correctly, I cannot go wrong, it is not clear how satisfactory this is as a response to the sceptical doubts Descartes has raised. S ECTION 5: G ODS AND D EMONS The evil demon argument turned upon what appeared to be a structural weakness in our cognitive faculties, namely that whatever we do with them, however hard we try, however careful we are, we could still end up with false beliefs on a very large range of matters. Desacrtes’ appeal to a benign God does nothing to remedy that weakness in our cognitive faculties: instead of an evil demon arranging things so that our best attempts still result in false beliefs, we have a good God arranging things so that our best attempts result in true beliefs. Either way, we are epistemic victims, whose success or failure as enquirers is beyond our control. Consider an analogy: Suppose that I like to bet on horse racing. I study the horses’ form, the conditions of the racecourse on the day of the race, the jockey’s skills and generally do everything I can to pick a winner. Suppose there are three theories about how the result of the race is determined and I don’t know which is true: it is random; it is fixed by someone who wants me to lose my bet; it is fixed by someone who wants me to win my bet. This is the sceptical position. Now Descartes gives us a ‘proof’ of the third of these: the result is fixed by someone who wants me to win my bet (so long as it is placed upon proper study of the form etc.). 5 That is good news for me, but it doesn’t make those facts about form and racecourses any better evidence, any more persuasive as grounds for betting, than either of the other two hypotheses. It seems that the reason Descartes finds the appeal to God so convincing is that he has surreptitiously smuggled in a difference between how the evil demon and the benign God do their work. The evil demon changes the world to make my beliefs false. In contrast, Descartes’ God appears to have created my faculties in such a way that they track the facts about an independently created world. Now it is true that this would be epistemically reassuring. To go back to the betting analogy, Descartes is actually offering a fourth scenario, one in which a being who wants me to win achieves his goals by making sure that the facts about form and racecourses and jockeys actually do serve to pick the winner. Then my bet would be safely placed. This looks like cheating in the argument with the sceptic. If there was something about my beliefs that ensured that they were non-‐contingently related to the actual world, then the sceptical hypothesis would not be genuinely conceivable. But Descartes is not challenging its conceivability, just its truth. So neither my beliefs nor the world which would make them true contain the structures of necessity which would remove the hyperbolic doubt. Instead the reassurance is meant to come from the fact that the actual belief-‐ world pairings have been selected by a being who wants to mimic such relations. It is as if there were such relations as would serve to underwrite the truth of my beliefs about the world. I suspect that Descartes’ satisfaction and our dissatisfaction with such an approach stems from his ability to see the whole universe as something created for us, that is, in our interests. That world view is no longer historically available, even to theists. Our recognition of the vastness of the universe and the relative insignificance of humanity makes the perspective seem hubristic. And our awareness that there are plenty of actual and – nomologically – possible creatures (note the etymology of this word!) whose best beliefs don’t match reality immediately brings the sceptical argument back into play. Contact: tom.stoneham@york.ac.uk / @tomstoneham