Thursday, August 8, 2013

Descartes' case for doubt in Meditation 1

To: Max W.
From: Geoffrey Klempner
Subject: Descartes' case for doubt in Meditation 1
Date: 13th August 2010 12:21

Dear Max,

Thank you for your email of 7 August, with the revised version of the essay which you originally sent on 5 August for the University of London Diploma 'Introduction to Philosophy' module, in response to the question, 'What reasons does Descartes give for doubting all our beliefs? Are they good reasons?'

There's a lot of good stuff here, which shows that you have thought hard about the arguments in the First Meditation. Quite a few students get tripped up by the difference between 'reasons' for doubting all our beliefs and Descartes' 'motivation' for putting forward these arguments in the first place. You clearly distinguish the question of motives in your second paragraph. But what light is shed on Descartes' reasoned arguments by consideration of his motives?

There's a point worth making here that for Descartes, the experience of discovering that what you thought you 'knew' or were certain about is false, should lead the rational inquirer to seek to determine a sounder basis for knowledge. But supposing you had this: would that mean that you *never* got things wrong? In the Sixth Meditation Descartes shows he is fully aware that an explanation is needed of how, even if God is not a deceiver, we sometimes form false judgements, owing to circumstances beyond our control. A better take on this would be that Descartes' aim is to reason out a philosophical system. The beliefs he is concerned about are a priori, necessary truths. It is not at all implausible to suppose that in order to construct such a system, one needs an indubitable foundation, in axioms which cannot be doubted.

Leaving that aside, there is another question about the 'four arguments': The way you present your exposition gives the impression of Descartes offering one argument, then when the audience is not fully persuaded offering another argument, and then a third and so on like a sideshow huckster. 'Wait to you get to my fourth argument, it's a doozy!' I just don't believe this. The Meditations gives every impression of being a work which was composed with enormous care. It is one of the great works of Western Philosophy. So I think something different is going on.

Regarding the first argument, the 'argument from illusion', you make a very valid point that appearances are not the same as illusions (although you could have said this explicitly). The small child may wonder, 'Why does the sun always follow me around?' whereas we grasp that this appearance is explained by the sun's distance. However, when all is said and done we *do* sometimes get deceived by appearances, we are sometimes illuded.

The answer to this, which Descartes provides himself, is that we rely on our senses to correct such errors. But in that case, why even bother giving this argument? The answer, I think, is that Descartes has established (or thinks he has established) a fundamental principle: that when we perceive an object, we have an experience which we read or interpret in some way in order to arrive at a judgement about that object. In other words, he has opened up a gap which he will go on to exploit.

The idea that all my experience could be a 'permanent dream' would not make any sense unless we had accepted the conclusion of the first argument, that there is a 'gap' between experience and reality.

You have noted (as many of my students fail to do) that Descartes considers briefly an even more scary possibility, that 'I am a madman'. Is he right to leave this on one side? If you are going in for arguments for doubting your beliefs, isn't this one you should certainly consider? The egocentric notion that I am the ultimate judge of what is or is not reasonable is one that was to continue until the linguistic turn, and Wittgenstein's argument against a 'private language'.

You find lots of problems with the 'third argument' concerning the possibility that 'God is deceiving me'. I think that you are missing the rhetorical purpose here, which is to raise the question of whether the thing we consider to be 'God' necessarily has the attributes of omnipotence and omnibenevolence. If it is not logically impossible that an omnipotent being exists, or at any rate a being sufficiently powerful to deceive me (which requires a lot less than 'infinite' power) then if we are looking for ways in which beliefs 'might' be false, then this is a valid reason.

But what exactly is the 'belief' in question? You rightly point out that Descartes' 'evil demon' is hardly different from Berkeley's God. The point here, however, is that Berkeley denied the coherence of the very thing that Descartes wishes to raise a sceptical doubt about, namely, the existence of a 'material' world. This is no 'Matrix' scenario, where the truth consists in a different way that objects are arranged in space and time. There is no 'space' as such, only the spatial field of our experiences. Berkeley is saying, in effect, that this is no deception, when you reason it through. That's how he is able paradoxically to claim that he is defending 'common sense'.

Good point at the end about Hume, which underlies what I said at the beginning, that the 'knowledge' in question is a philosophical system (in which 'the real distinction between the soul and the body of man' is 'demonstrated'). For Hume, all such metaphysical wranglings are to be committed to the flames.

All the best,