laura@utcsstat.UUCP (Laura Creighton) (01/11/84)
Rene Descartes was born on March 31, 1596, in a small town near Tours. He died in 1650. Thus he was a contemporary of Galileo, Kepler, Fermat, Mersenne, Pascal and other "famous people". he did most of his work in Holland. In these times, after centuries of mediaeval theological embellishments on the works of the Greek philosophers, it was believed that all of the real work of enquiry and philosophy was done. A few extra bits may have been needing, but all in all there was a belief that everything that was going to be understood had been pretty well understood. Mathematicians (and Descartes was always a mathematician first and a philosopher second) wrote down new theorems as "additions to foo" where foo was some great Greek mathematician, often Apollonios. Quoting Aristotle was sufficient to prove one's point, and a good Christian education consisted of lots of ancient philosophy, theology (mostly Thomas Aquinas who is in turn mostly Aristotle) and very little else besides. So Descartes has 2 problems. he wants to do something new in a society which is unwilling to admit that something that is new can be done, and he wants to set down the foundations for what will eventually be called "rationalism". Note that this does not imply that Descartes wants to do away with the Church, far from it! he maintained reasonable relations with the Jesuits throughout most of his life and it was his ardent desire that his work be accepted and taught by them in school. Moreover, he was a devout Christian and a good deal of his foundation depended (as he saw it) on his belief in God. It is true that later rationalists were able to use his model without God, but this does not date to Descartes. Why this could happen we will get to later when we discuss Descartes's proof for the existence of God. Descartes wants to set out a foundation for the acquisition of true knowledge. How does one know anything? In practice, the things that one knows one either knows because one has directly experienced them, or because someone else, whom you believe, has experienced them. But one can be mistaken about what one has experienced, so this is not, according to Descartes, a good foundation. Descartes resolves to: 1. Accept nothing as true which I did not clearly recognise to be so: that is to say, to avoid carefully precipitation and prejudice, and to accept nothing in my judgements beyond what presented itself so clearly and distinctly in my mind that I should have no occasion to doubt it. 2. Divide each of the difficulties which I examined into as many parts as possible, and as might be necessary in order best to resolve them. 3. Carry on my reflections in order, starting with those objects that were most simple and easy to understand, so as to rise little by little, by degrees, to the knowledge most complex: assuming an order among those that did not naturally fall into a series. 4. Last, in all cases make enumerations so complete and reviews so general that I should be sure of leaving nothing out. <Discourse on the Method> Okay. This is rather vague, but you can see what Descartes is trying to do. Now Descartes has a problem. You see, he dreams. And in his dreams he believes all sorts of things which he knows are false when he wakes up. But what if he is dreaming now? What can he find that is not corrupted by such a possibility? Descartes finds that he is left with "I am thinking". Thus there must be an "I" who is doing the thinking! Cogito ergo sum -- I think, therefore I am. Descartes proceeds to define himself as 'that which thinks'. Because he can think of himself without a body (his soul, if you will) he does not identify himself with any physical sensation or his physical body. He, Descartes, is the thinking thing which is indeed imprisoned in a corporeal body which misleads him with such things as optical illusions and pains him with hunger, suffering and a host of other imperfections. Descartes is not his body, rather his body is merely an extremely intimate tool which he uses. But what can Descartes *be*? Descartes ends up identifying himself with his pure thoughts which he finds in himself. These are pure thoughts like the thoughts of mathematics and logic. And there is one other important principle: the law of sufficient cause. Now it is manifest by the natural light that there must be at least as much reality in the efficient and total cause as in its effect. For where, pray, could the effect get its reality if not from the cause? And how could the cause supply the reality to the effect, unless it possessed it itself? From this it follows not only that something cannot proceed from nothing, but also that which is more perfect -- that is contains more reality in itself -- cannot proceed from that which is less perfect. Okay. Now here goes -- Descartes' 2 part proof that God exists. Firstly, the law of cause and effect explain why things happen in the real world. But the real world itself must have a cause, and that cause is God. it is not sufficient to bring up the old arguement that all the world could be a dream, because clearly it is not so, even though we can never be sure that our sense percgptions are not lying to us at any given moment. they are not *always* lying to us. What caused the world? God. Moreover, Descartes, who knows himself imperfect, can think of God. Where can this idea of a perfect being come from? it cannot come from the imperfect Descartes, since that would have "something which is more perfect proceeding from something that is less perfect" -- so it must come from something which is not less perfect than perfection, that is which is perfection, that is which is God. Therefore God exists. Now, if you are reading this and finding these irrefutable evidence for the existence of God, you are going to get a big shock when the essay on Hume comes out. this is not a very good argument at all. You might also note that while these arguments give you the existence of "God" as in something that is perfect, they don't give you the Christian god. That never bothered Descartes, who as a Christian, already knew what he was looking for. It did bother some of Descartes followers. they took his idea of the truth of mathematics and logic and used them to develop a philosophy which was later called "rationalism". There are an awful lot of rationalists out there now -- including almost every atheist that you might find. In general, to play the game of "spot the rationalist" you have to look for someone who has these beliefs: the law of cause and effect is a truth. there is truth in mathematics (alternately, it is possible to express all truth by way of mathematics). they think of themselves as thinking beings -- it is the thinking that matters most to them. now -- do you think that you can spot a few rationalists? moreover, can you see that the "Can creationists contribute to science?" article was an appeal to make science rationalist? All it left open was the existence of God, which, as i have shown does not really matter to the central tenets of rationalism. However, the empiricists and the existentialists are going to find real serious trouble with this proposal. I will get to them later this week. Laura Creighton utzoo!utcsstat!laura