Monday, March 26, 2007

My complaint with Descartes

I would like to have an interpretation of Descartes' work that does not charge him with a huge error. I'm not sure my charge is exactly the circularity charge that DePoe is struggling with but here is how it goes.

I am inclined to agree, even though some poeple don't, that Descartes successfully proves that "I think" and "I exist are immune from doubt. But then Descartes does something that strikes me as weird. First, he asks himself how he became convinced of the conclusion of the cogito argument and concludes that he accepts it because he clearly and distinctly perceives it to be good. Hey wait a minute Descartes? Didn't you just produce a self-refutation argument against the claims "I do not exist" and "I do not think." As a result he claims this supports his clear and distinct criterion. Then he considers whether or not God exists, and he does this in order to reassure himself that his clear and distinct perceptions are not Satanic deceptions. But to do this, it seems to me that the premises of his arguments have to be premises he can be sure of, even if Satan is controlling his mind. This argument, the argument based on the cause of his idea of God, fails to achieve this, even if it were a good argument (and I don't think it is a good argument).

1. Something cannot be derived from nothing. In other words, all effects, including ideas, are derived from something.
2. There must be at least as much reality in the cause as there is in the effect.
3. I have an idea of God (as an infintie and perfect being).
4. The idea of God in my mind is an effect that was caused by something.
5. I am finite and imprefec t, and thus I could not be the caue of the idea of an infinite and perfect God.
6. Only and infinite and perfect GOd could be the cause of such an idea.
7. Therefore God (an infinite and perfect being) exists.

What is the most charitable way to read this?


exapologist said...

I'm not sure if it helps, but by my lights at the moment, I thing the following is an accurate formulation of Descartes' argument in the Third Meditation for his clarity and distinctness criterion:

1. I am certain of the following proposition, P: that I am a thinking thing.
2. The only thing that accompanies P in my mind is the clear and distinct perception of P.
3. If I am certain of P, and the only thing that accompanies P in my mind is the clear and distinct perception of P, then the clear and distinct perception of P is the basis of P’s certainty.
4. Therefore, the clear and distinct perception of P is the basis of P’s certainty.
5. If it’s possible to have a clear and distinct perception of a false proposition, then the clear and distinct perception of P is not the basis of P’s certainty.
6. Therefore, it’s not possible to have a clear and distinct perception of a false proposition.
7. If it’s not possible to have a clear and distinct perception of a false proposition, then having a clear and distinct perception provides a general rule for determining when a proposition is true.
8. Therefore, having a clear and distinct perception provides a general rule for determining when a proposition is true.

Jason Pratt said...

Well, Victor's formulation of Descartes' ontological argument isn't circular, at least. That's something charitable I can say for it. {shrug}{s!}

I'm pretty sure there's a category error in it, though. (I have a clear and distinct perception of that in my mind {g}; though admittedly I'm having trouble figuring out how to phrase it.)

Johnny-Dee said...

This is related with some of the problems related to the Cartesian circle, but I think you're right to locate these as a separate issues. There are many approaches to trying to figure out Descartes's reasoning here. I'm somewhat sympathetic (but in no way absolutely committed) to the view that the cogito and wax discussions come before the third Meditation in order to teach the meditator how to arrive at Cartesian truths. So, one way to read Descartes's justification for each of these premises in the argument for the existence of God is that when one carefullly thinks about these premises, their truth becomes apparent in the exact same way that the truth of "I think, I exist" is apparent.

Interestingly, there is no reference to "clear and distinct" perception to justify these premises in the second or third Meditation. Rather than these premises being derived from Descates's "clear and distinctness rule" which is introduced in the fourth Meditation, it seems possible that the clear and distinctness rule is derived from Descartes's inferences in the second and third Meditations. Dugald Murdoch has an article in the Philosophical Review called (I think) "The Cartesian Circle" (1999), which seems to defend the basic view I'm sketching here.

exapologist said...

I can't speak on the paper by Murdoch you mention, but if it's anything like his paper on Descartes' notions of intellectual exclusion vs. abstraction, it must be good.

exapologist said...

Actually, Descartes does discuss the clarity and distinctness rule, as well as it's justification, in Meditation 3 (although of course you're right that he also discusses it in Meditation 4). Below is the relevant passage from the Third Meditation on which I based my posted reconstruction:

"I am certain that I am a
thinking thing; but do I not therefore likewise know what is required to
render me certain of a truth ? In this first knowledge, doubtless, there is
nothing that gives me assurance of its truth except the clear and distinct
perception of what I affirm, which would not indeed be sufficient to give me
the assurance that what I say is true, if it could ever happen that anything
I thus clearly and distinctly perceived should prove false, and accordingly
it seems to me that I may now take ^ a general rule, that all that is very
clearly and distinctly apprehended (conceived) is true."

Brandon said...

Well, what exactly the most charitable reading will be will depend on other background views. I don't know if this will help, but I would suggest going about it this way (I've found, at least, that it makes initially skeptical students more sympathetic to the argument, even though they are, unsurprisingly, never completely won over): Given this argument, what would Descartes say to attempts to explain away the idea of God -- e.g., in a Freudian way as an amplified father figure, or in a Durkheimian way as a personification of society, or in a Darwinian way as the result of an agency-positing mechanism of some sort? He would argue that these explanations don't actually explain this idea of God as infinite perfect being, because they all ignore precisely the key characteristic needing explaining, the 'infinite and perfect' part. There is a disparity -- an infinite disparity, so to speak -- between the finite explanans and the infinite explanandum.

In any case, Descartes doesn't need God to reassure himself that his clear and distinct perceptions are not deceptive; if you are clearly and distinctly perceiving X, you already know you can't be deceived about X as perceived. What God does (as far as clear and distinct perception goes) is enable you to accept clear and distinct perception in general in this way, so that when you are not clearly and distinctly perceiving X you can still say that in clearly and distinctly perceiving X you couldn't be deceived. In other words, by clearly and distinctly perceiving the idea of God, you can do without having to perceive clearly and distinctly every little relevant thing all the time for every circumstance, because God undergirds reliability of cognition in general (God is not a deceiver). But that's an argument that requires more than just the existence of God. It requires the God-is-not-a-deceiver theodicy of Meditation Four as well. And, in fact, this is how Descartes prefaces the arguments for God's existence in Meditation Three. In Meditation One he gave a whole bunch of causes of doubt that, bit by bit, fractionated away everything even when common responses to them were allowed. In the rest of the Meditations he is rebuilding. When he gets to Meditation Three, he begins considering again the 'slight and metaphysical doubt' (as he calls it somewhere) about the ability of God, in all His omnipotence, to deceive him. So Meditation Three is really only setting up for Meditation Four, and this is very explicit. Together they give us general reliability of cognition; in Meditation Five we get rigorous certainty about body in abstract, and in Meditation Six we are restored to certainty-enough about actual material bodies. It's possible to see this as the culmination of the Meditations: to show what is required to be certain about bodies, even in the face of severe skeptical doubt. And to do this, Descartes needs a bridge principle that gets him out of the cogito alone and into the world, one that is strong enough, if established, to yield certainty about the world (i.e., something stronger or more universal than the cogito), but is accessible enough that it could be reasoned about without appealing to bodies at all. And that's where the idea of God comes in.