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Honors History 102
Feb 12, 1990
Rene Descartes is one of the greatest French thinkers of all time. He is considered by some to be the founder of modern philosophy. In 1673, Descartes wrote his now famous Discourse on Method in which he describes a method with which a person could investigate the unknown. The major principle of this method is the idea of universal doubt. By using universal doubt, Descartes probes that he exists and that God must also exist. It seems to me, however, that Descartes does not use a complete idea of universal doubt; he only partially applies what I believe this doctrine should consist of. I also feel that Descartes' use of universal doubt to prove the existence of God is not strong enough to be valid.
To investigate the unknown, Descartes first determines exactly what he knows to be true. After applying the idea of universal doubt, he arrives at the conclusion that the only thing he knows for sure is that he exists. He arrives at this conclusion because he realizes that to doubt, he must be able to think, and that because he thinks, he exists. It seems to me that this logic is incomplete. I believe that if he carries his thoughts a little farther, he could end up doubting his own existence, even though it may only result in a shred of a doubt. Descartes can doubt the existence of other people. He also has to doubt the nonexistence of other people. If other people exist, then obviously they can doubt that he exists. This gives a reasonable doubt of his own existence. I am not sure what this makes him, possibly the figment of someone else's imagination, but it does lead to a doubt of his own existence.
I also believe that Descartes is only partially complete in his use of what I would call a complete idea of universal doubt. He doubts the validity of all of the truths he has accepted, all of the facts of the world, but, to universally doubt everything, I believe he has to also doubt the invalidity of all of the ideas and beliefs that he has condemned as false. In his use of the idea, I believe he is incomplete. For example, Descartes may doubt the existence of God, but, to doubt all things, I believe he would also have to doubt the nonexistence of the Greek pantheon, the Norse gods, and all other religious ideas he has heard of but labeled as untrue. I do not believe he did this when he tried to doubt all things and I think he would have had to to universally doubt everything.
To prove God's existence, Descartes reasons in the following manner. He first realizes that he doubts. He then states that it would be closer to perfection to know than to doubt. Thus, he comes to the conclusion that he is not perfect. He must have received his idea of perfection from somewhere and that somewhere must be God since there is nothing on earth that is perfect.
This logic seems to work at first glance. It seems to me, however, that it is possible for an idea of perfection to come from everyday experience. All around us there are examples of people who are good at certain things and other people who are either better or worse at these things. As a result, we get the idea that one person is more perfect than another at a certain activity (or in a certain virtue). We then expand our limited idea to make it all encompassing.
A geometric analogy (which Descartes liked to use so much) may be parallel lines. We see lines that are maybe one inch long and exactly one inch apart. We call these lines parallel. We then extend the lines to "infinity." We say that the lines will always be parallel, even if they go on forever.
We may not have received neither our ideas of perfection nor of infinite parallel lines in the way I have explained above. However, it certainly is a possibility. Since it is possible that we received our idea of perfection in this way, I think Descartes would be forced to doubt that God is the source of his idea if he is truly using the idea of universal doubt.
I do not believe that the use of universal doubt is a very effective system when trying to prove an idea or inquire into the unknown. It seems that it would not get a person anywhere in the search for knowledge. In effect, universal doubt causes every person to start with nothing as his base of knowledge instead of building upon the stores of past generations. If this had become the basic principle of the scientific method, scientific knowledge would not have grown since the time of Descartes.
To truly doubt all things, the idea of universal doubt must encompass not only ideas that are considered fact, but also those that are considered fiction. A person must not doubt only what he believes to be true, but also that which he thought was false. Only then do I believe a true idea of universal doubt is employed.