June 26, 2006

How I spent my summer vacation XI

Wow ... two weeks to the day since the last edition. In that time, I finished the Aquinas and Scotus (more or less). I won't be blogging those. Instead, we move on to the early Moderns. Descartes went quick, and I'm already more than halfway through Hobbes; but you'll have to wait for him until tomorrow-ish (Wednesday if grading my algebra class' exams take too long).

Descartes, Meditations on first philosophy, with selections from the Objections and replies

After trudging through hundreds of pages of incredibly technical and esoteric scholastic metaphysics, I can finally understand why his approach to philosophy took Europe by storm. Gone are the abstruse foundations of matter/form and potential/act. Gone are the endless concerns about the ontological status of 'whiteness'. And, characteristically of Modern philosophy, gone is the notion that philosophy is, roughly speaking, the remainder when revelation is subtracted from theology. Thus, in Descartes, we see an approach to philosophy that is accessible to all intellectuals -- not just those who have spent a decade immersing themselves in scholastic Aristotelean theology.

The Meditations is familiar to just about anyone who has studied at least a little philosophy in college. This is probably due to its tight, precise, and especially nontechnical, presentation, making it far more accessible to your average first-year undergrad than most any other Great Book in the Western philosophical canon. In addition, the six individual meditations are each just about the perfect length for a single 50-minute lecture, meaning a two-week section on Descartes practically writes itself. Descartes even presents an outline in the introduction, explaining the content of each meditation.

The first meditation introduces Descartes' method of doubt. This takes place over three stages, each of which consists of a basis for doubt and consequent doubt over certain beliefs. First, the meditator realizes that the (external) senses are unreliable: towers might appear round far away but square close up, or a stick might appear bent when partially submerged in a pool of water, while remaining straight to the touch. Thus, we come to doubt our particular beliefs about the sensible world -- 'The tower is round', 'The stick is bent', etc. Second, the meditator considers dreams and hallucinations, during which I might falsely believe I am performing certain actions or my body is in certain physical states -- 'I am running' is, strictly speaking, false when I am dreaming, and yet I could easily believe it at the time. So now we must doubt the veracity of our proprioception or kinaesthetic experiences. Third and finally, we have the famous evil genius or evil demon hypothesis. This is the possibility of The Matrix: that I am so thoroughly immersed in the illusion cast over me by some malicious entity that (seemingly) every other belief I have retained thus far is suspect. I cannot be sure that I have not been so deceived that I am wrong in affirming '2+2=4' or that my beliefs about metaphysical simples such as time and extension are fundamentally mistaken. Along with the possibility of an evil genius comes doubt about religious belief as well -- how do we justify at least the fundamental theistic belief in a loving, personal God, if we admit the possibility that the omnipotent being is instead a Devil?

The resolution of all these doubts is the project of the remaining five meditations. The second is an attempt to secure an infinitesimal foothold for certainty amidst all this doubt: even if I have been thoroughly deceived in every other respect, I still know that I, a thinking thing, exist; otherwise, how could I be deceived? Descartes goes on to argue that I know myself, as a thinking thing, more reliably than I even know my own body.
1. Nothing is known per se except by the intellect.
2. Thus, my mind (that is, the ground for my intellectual power) is the easiest thing for me to know.
3. Thus, this knowledge is the most evidence and reliable that I can have.
4. Thus, my mind exists.
I'm not sure if 4 is exactly Descartes' conclusion, but it certainly seems close. 1 is an important claim, and Descartes defends it by considering our knowledge of a piece of wax. We claim to know the wax, even though all of its sensible qualities can easily be altered by simply moving it from a cold part of the room to near the fire; but then none of our per se knowledge is of its sensible qualities, so we can only know it per se via the intellect. By contrast, virtually every other Modern philosopher would conclude that we do not know the piece of wax per se.

In the third meditation, the meditator develops his first argument for the existence of God. Before this, however, we need an essential Cartesian doctrine: clear and distinct perceptions are necessary/sufficient for certain knowledge. There are two things to note here. First, 'perceptions' includes both sensible perceptions and the possesssion of nonempirical ideas; we will see arguments later that our idea of God is such a clear and distinct perceptions, yet it is obviously nonempirical. Second, it is not clear whether the meditator is taking this principle to give a necessary or sufficient condition, and this is a very important difference. In any case, with this principle in place, the meditator's plan is clear: we shall establish that we have a clear and distinct perception of God, and that this justifies at least our most fundamental beliefs about the external world of sensible objects.

The 'perfections' argument for the existence of God runs as follows (this is an extremely loose paraphrase):
1. The most perfect idea is my idea of God.
2. Effects must have a cause at least as perfect as they are.
3. Thus, my idea of God has a cause at least as perfect as its content.
4. Thus, this cause must be greater than me.
5. Thus, either this cause is God, or we can run through the argument again for it.
6. Thus, God exists.

Now that we know God exists, we realize that the idea of God, as the idea of an actual infinity, must be epistemologically prior to my knowledge of finiteness, ie, in order to know any limitation or defect, I must first know the perfect exemplar. Hence, the idea of God is even more clear and distinct than my idea of my own mind.

The fourth meditation defends the claim that God is no deceiver and gives an account of error. God is no deceiver simply because deception is no perfection, but a privation of the virtues of honesty and respect; but my idea of God is the idea of that being who has all perfections. The discussion of error is framed as a sort of problem of evil: if I am so prone to error, I must be quite defective as a knower; but why would a perfect creator create such a defective being? The meditator's solution is that the use of free will is one of the essential reasons for our existence; but the nature of this will means it is necessary unlimited, while as creatures our intellects are necessarily finite. The will thus exceeds our ability to understand, and we thereby come to make mistakes through a lack of prudence.

The fifth meditation vindicates the knowledge that was doubted in the third stage of the first meditation, including mathematics and rationalist metaphysics: we have clear and distinct ideas of all these concepts, so our knowledge of them is certain. The second argument for the existence of God takes up much of this meditation; it amounts to several unconvincing assertions that we have clear and distinct perceptions of God's existence, and that this is only possible if God, in fact, exists.

The sixth meditation deals with the remaining two stages of doubt. First we have a statement of Cartesian dualism, that while I have a body (because I have a clear and distinct perception of having a body), I am essentially only mind, and separable from my body (because I have a clear and distinct perception that the two are distinct). Second we justify our belief in an external material world -- but this is a slightly more sophisticated argument than simply appealing to clear and distinct perceptions, because the meditator certainly doesn't want to say that we have such perceptions in the case of dreams and hallucinations.
1. I have been inclined by God to believe that my sense-perceptions are caused by material things.
2. God is no deceiver.
3. Therefore, my belief in 1 is accurate.

The selections from the Objections and replies serve mostly just to clarify Descartes' already rather clear positions. There's some discussion of 'analytic' versus 'synthetic' presentations of arguments and the relation between necessary truths and God, but we'll pass over those for now. One important objection (because it came up on one of the previous exams) comes from Arnauld, a theologian and one of the first proponents of Cartesianism:

we can be certain that God exists only because we clearly and evidently perceive this fact. Therefore, before we are certain that God exists, we ought to be certain that whatever we clearly and evidently perceive is true.

Thus, Arnauld says, Descartes' argument is "viciously circular": we can only be certain we have a clear and distinct idea of God when we already know God exists, and thus cannot (as in the fifth meditation) use this perception to argue for God's existence. Descartes' response seems to be a non sequitur, amounting to a distinction between clearly perceiving something now and recalling later that we did clearly perceive it at that time. A better response would be to hope that, somewhere in the rather obscure fifth meditation (the only part of the book that is obscure), Descartes has given independent grounds for maintaining that the idea of God is had clearly and distinctly.

Total pages read: 1124

Interesting philosophical link: Can theism answer The Deepest Questions?


MosBen said...

My first year philosophy prof. referred to the circularity of Descartes' argument in the Meditations and said that there is at least some proof that Descartes was aware of the circularity. She didn't really go into it much, but there was at least some implication that this showed that Descartes didn't actually believe in the argument.

Noumena said...

Who did you have for that?

MosBen said...

Not a clue. Some lady with black hair and glasses. I don't think she was a permanent member of the faculty.