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Taming the Skeptical Dragon

Toni Vogel Carey on a misunderstanding between her Aunt Polly and René Descartes.

When I began studying philosophy, my Aunt Polly, who had a head more for business than for abstract ideas, wanted to know just what philosophy is. Instead of doing the sensible thing, though, and giving an explanation she might readily understand, I waxed Cartesian. “How can we be certain,” I asked, tapping on her dining table, “that what looks and feels to us like a table, or a hand, is not just an illusion created by an evil demon to deceive us?” Sorry she had ever asked, she suggested, “I guess you could test it with acid.”

The Cambridge philosopher G.E. Moore (1873-1958) was one who tried to bring philosophers “back down to earth,” as Barry Stroud says, and Aunt Polly would no doubt have understood his ‘refutation’ of external-world skepticism:

I can prove now, for instance, that two human hands exist. How? By holding up my two hands, and saying, as I make a certain gesture with the right hand, “Here is one hand,” and adding, as I make a certain gesture with the left, “and here is another.”

The problem is, she would probably have found this ‘proof’ too obvious to mention, which would only have perplexed her more. Philosophers too are perplexed because, like Aunt Polly, Moore seems to miss not only the bull’s eye, but the entire target. How could this shining example of philosophical temperament and reasoning be so blind to the Cartesian challenge? Stroud can only reply, “I would like to know.”

The best-seller Men are from Mars, Women are from Venus is about the battle of the sexes, and catalogs the miscommunications caused by gender differences. Descartes and Aunt Polly too have a communications problem, but not because she is a woman and he a man. Their mismatch, and Moore’s place in it, are the mysteries I try to fathom here, with help from some splendid asides by Moore’s friend Ludwig Wittgenstein. All italicized quotes are from Wittgenstein’s On Certainty.

Moore makes clear in ‘Four Forms of Skepticism’ that skeptical doubt is not real doubt:

To say that a man is sceptical about certain sorts of things, or holds certain forms of scepticism, does not necessarily imply that he is in doubt about anything whatever. A man who, like Bertrand Russell, believes with the utmost confidence that he never knows for certain such a thing as that he is sitting down, may nevertheless feel perfectly sure, without a shadow of a doubt, on thousands of occasions, that he is sitting down.

Skeptical doubt, Stroud says, requires “a certain withdrawal or detachment from the whole body of our knowledge of the world.” And as even Aunt Polly’s acidic ‘solution’ makes clear, laypeople and scientists alike are solidly “of this world.” The peculiar feature of philosophical doubt is its utter irrelevance to anything we encounter in ‘real’ life. Were we to accept skepticism about the external world, that is, we would carry on just as we do, continuing to deal, if not with the vicissitudes of life, then with what appear for all the world to be so.

And couldn’t we peacefully leave him to doubt it, since it makes no difference at all? #120

Aunt Polly could experience only real, or what Stroud calls ‘internal,’ doubt; the ‘external’ philosophical variety was lost on her. After all, detachment from the commonsense point of view is not something the commonsense point of view itself can provide. The problem with this ‘internality,’ though – the problem facing both Moore and Aunt Polly – is its failure even to address, let alone answer, the Cartesian challenge. Of course, her ‘solution’ is circular and comical, whereas his ‘refutation’ seems question-begging and not funny at all. But while Moore’s approach seems un-philosophically ‘internal’ when compared with that of Descartes, he clearly advances a philosophical position about commonsense thinking, in contrast to Aunt Polly’s commonsense thinking about a philosophical position.

For when Moore says “I know that that’s …” I want to reply “you don’t know anything!” – and yet I would not say that to anyone who was speaking without philosophical intention. That is, I feel (rightly?) that these two mean to say something different. #407

Moore gives what philosophers call a ‘paradigm case argument’ against the skeptical thesis, ‘pointing’ ostensively to a counterexample (“here is a hand”). And of course, if he has found one counterexample, then there is no end to them.

If you do know that here is one hand, we’ll grant you all the rest. #1

Moore maintains that this proof is “a perfectly rigorous” one, that “it is perhaps impossible to give a better or more rigorous proof of anything whatever.” He is aware, though, that skeptics demand more than this, “something like a general statement as to how any propositions of this sort may be proved.” And “if this is what is meant by proof of the existence of external things,” then “I do not believe that any proof of the existence of external things is possible.” For in order to give that sort of proof, “I should need to prove that I am not now dreaming. But how can I prove that I am not?”

At this point, many would say, Moore simply concedes the match to Descartes. But Moore rejects the idea that if you cannot prove a proposition in the way skeptics require, then you don’t really know it; he thinks we can know things that we cannot thus prove. And most philosophers, Aristotle included, would agree with Moore that there are propositions which neither need nor admit of proof – although, of course, what Aristotle has in mind is the law of non-contradiction, not “this is a hand.”

The questions that we raise and our doubts depend on the fact that some propositions are exempt from doubt. #341

The Cartesian dreaming-waking problem goes to a second, more familiar ‘internal-external’ distinction. This one pits the subjective certainty provided by private (internal) sense experience against the objective, public knowledge of (external) things “to be met with in space,” as Moore puts it – things that are the way they are, Stroud says, “quite independently of [their] being known or believed by us to be that way.” The tree falls in the forest, in other words, even if nobody hears it.

A mental state of conviction may be the same whether it is knowledge or false belief #42

Brief as it is, there are four distinct forms of certainty contained in this account of skepticism, ascending from experiential to abstract, and from particular to universal:

4. The certainty of foundational or ultimate truths.

If you tried to doubt everything you would not get as far as doubting anything. The game of doubting itself presupposes certainty. #115

3. The certainty of deductive proof.

If I say “I know” in mathematics, then the justification for this is a proof. #563

2. The certainty of ground-floor commonsense truths.

There cannot be any doubt about it for me as a reasonable person. – That’s it. #219

1. The certainty of my own immediate ‘internal’ experiences.

I want to conceive it as something that lies beyond being justified or unjustified; as it were, as something animal. #359

To philosophers, this four-fold hierarchy seems both comfortably old-fashioned and uncomfortably out-of-date, which is understandable, since its architecture dates back to Aristotle’s Posterior Analytics.

4. Intuitive grasp of first principles.
3. Demonstration; knowledge of universals – ‘scientific’ or metaphysical.
2. Opinion, generalization, the craftsman’s know-how.
1. Sense perception, experience of particulars.

There are differences, of course. Aristotle’s hierarchy starts with the ‘external’ perceptions of individuals, whereas the latter-day one begins with ‘internal,’ private ‘sense-data’ – a term introduced by Moore himself. And for Aristotle, the second level is closer to opinion than to bona fide knowledge. Whatever the discrepancies, though, they pale in contrast to the strong ‘family resemblance.’ So to Stroud’s query, “Where exactly does Moore go wrong?” perhaps the answer should be, He makes a hierarchy-mistake. More than one, in fact, given his failure to reach both third-level and second-level ‘externality.’

Not all corrections of our views are on the same level. #300

The hierarchical reason why paradigm-case arguments fail is that they attempt to wage a ‘second-level’ battle against a ‘third-level’ adversary. Take the linguistic set-to between Professor Susan Stebbing and Sir Arthur Eddington in the 1930’s, over the ‘solidity’ of ordinary objects like Aunt Polly’s table. Eddington says they are full of holes, and mostly just empty space. But in that case, Stebbing objects, “where can we find an example to show us what ‘solid’ means?” Tables are paradigm examples of what we commonly mean by the word ‘solid’, so to deny their solidity borders on the absurd.

Stebbing and Eddington had a communications problem – not, again, because she was from Venus and he from Mars, but because she took a commonsense, macro-, and he a theoretical, micro-viewpoint. They could agree that tables are solid in the ordinary (second-level) sense; we can pound our fists on them, and the like. To her, though, fist-pound-ability constituted an ‘important criterion’ of solidity (to use Michael Slote’s term), whereas theoretical physicists like Eddington have little or no use for such gross characteristics.

Moore follows the thinking of Thomas Reid and the eighteenth-century Scottish ‘commonsense school,’ that if philosophy conflicts with common sense, then something is wrong with philosophy. Moore’s position, similarly, is that any argument against his claim to know that this is a hand would have to be based on a premise less certain than his claim to know that this is a hand.

The strange thing is that when I am quite certain of how the words are used, have no doubt about it, I can still give no grounds for my way of going on. If I tried I could give a thousand, but none as certain as the very thing they were supposed to be grounds for. #307

Interestingly, Charles Larmore presents a hierarchical form of this argument from relative certainty, and considers it “a distinctive feature of Moore’s epistemology.” This is that “(first-order) knowledge claims,” e.g., this is a hand, “are more certain than any (second-order) principles” used to assess them.

The big question is whether third-level certainty, being higher, takes precedence over lower-level forms, or whether second-level certainty, being more basic, undercuts higher-level forms, and Cartesian doubt along with them. It is important to see, though, that this question itself implies that philosophical skepticism resides at some level(s) and not others. And that, in turn, means it has its limits, and cannot contaminate the entire epistemic spectrum, reducing philosophers to a Cratylan wag of the finger. The four-fold quasi-Aristotelian hierarchy brings with it a kinder, gentler ‘mitigated’ form of skepticism, one that Hume actually advocates as a cure for dogmatism. It reminds us to frame assertions conditionally rather than categorically, that “a degree of doubt, and caution, and modesty” must accompany all our thinking. In this respect, skepticism is relevant after all to ‘real life’.

Speaking of modesty, one glaring way those who know less display their ignorance is by placing themselves above those who know more. But it is arrogant too for third-level thinkers to dismiss second-level types as beneath them. What Moore serves to remind us is that they need Aunt Polly’s world a lot more than she could ever need theirs.

I am sitting with a philosopher in the garden; he says again and again “I know that that’s a tree,” pointing to a tree that is near us. Someone else arrives and hears this, and I tell him: “This fellow isn’t insane. We are only doing philosophy.” #467

Just as philosophical doubt is unlike ‘real’ doubt, philosophical insanity is unlike real insanity. In 911 emergencies, it would be not only comic, but tragic – indeed insane – to stop and question the existence of external objects. In a philosophical discussion, though, as Aunt Polly shows, it can be comical not to do so. “It is one thing to philosophize and another to live,” as Richard Popkin explains the position of Huet, a seventeenth-century French skeptic; and propositions that are “philosophically dubious” may nevertheless be “acceptable or even indubitable as living options.”

We cannot say categorically, then, that the third level overrides the second, nor either that the second undercuts the third. The strength of Moore’s ‘refutation’ is that “here is a hand” may be just as certain in its own way as Cartesian indubitability is in its way, or even perhaps as the law of noncontradiction is in its way. The weakness of Moore’s argument is that certainty at one level is not transportable to other levels. Lacking a hierarchical perspective, Moore may have assumed transportability, and so taken certainty at one level for certainty at every level. That would constitute a philosophical mistake, but not the degree of mental obtuseness that we find so incongruent with Moore’s work.

“It is certain that we didn’t arrive on this planet from another one a hundred years ago.” Well, it’s as certain as such things are. #184

Is hierarchy the order of nature, or something we ourselves introduce? I do not try to answer this question here, nor either whether a four-fold hierarchy provides the best epistemic architecture. Hierarchies are anathema these days, in some cases for good reason (think of the caste system). Nevertheless, they are too well-entrenched in our culture to disappear any time soon. From the corporate ladder to military, ecclesiastical, and even academic rank, ‘upward mobility’ is the aim. Science is ‘topdown’ or ‘bottom-up’. We aspire to ‘high ideals,’ and try not to ‘lower’ ourselves to the level of those who do us wrong. Heaven is up and hell down.

The literature on philosophical skepticism has been dominated by an either-or debate between radical doubt and commonsense realism. But perhaps there is a Third Way – a hierarchical, or more accurately, a meta-hierarchical perspective. This architecture has the double-advantage of encompassing all (four) levels, while simultaneously allowing a detached assessment of their individual strengths and weaknesses. The result is to render skepticism compatible not only with the truth of things we claim to know in ordinary life, but with the truth of our claim to know them. And that goes a long way toward taming the skeptical dragon, and relieving philosophers of the legendary need to slay it.

© Toni Vogel Carey 2002

Toni Vogel Carey is a philosophy-professor-turned-personal-counselor -and-independent-writer. She is on the board of directors of the National Coalition of Independent Scholars, and is a US editorial advisor for Philosophy Now. Her most recent folly is a seminar/ support group called the Wise Club (named after an 18th century Scottish learned society).

René Descartes, Meditations (1641).
David Hume, An Enquiry Concerning Human Understanding (1748).
G.E. Moore, ‘Proof of an External World’ (1939), in Philosophical Papers (1959).
Richard Popkin, ‘Skepticism’, Encyclopedia of Philosophy, P. Edwards, ed., vol.7 (1967).
Barry Stroud, The Significance of Philosophical Skepticism (1984).
Ludwig Wittgenstein, On Certainty (written c.1950), G.E.M. Anscombe & G.H. von Wright, eds. (1969).

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