Descartes and the Existence of God
Once Descartes has realized that he can know with certainty that “I exist” is true, he continues to build on his foundation of truths. The truth about the nature of God, proof of God’s existence, and the nature of corporeal objects are considered, among others, after Descartes proves his existence. Descartes’ principal task in the Meditations was to devise a system that would bring him to the truth. He wanted to build a foundation from which all further philosophical inquiry could be built. It was essential that his beliefs were sound. If any one of them were at all in doubt, then it put the credibility of the whole structure of knowledge in jeopardy. I will discuss a few of the topics Descartes analyzes after his epiphany of existence. Throughout the essay, I will raise some doubts that I have pertaining to Descartes’ conclusions as well.
In his second meditation, when Descartes pushes the method of doubt to its fullest extent, several truths survive; since these cannot be doubted Descartes must know them. The first of these is that “I exist.” The second truth, when Descartes asks “what am I?” caught my attention. I found it odd that he tests potential answers by asking whether he can doubt them. The test appears strange because one’s ability to doubt something doesn’t normally show that it is false. If I can doubt that I have the hairiest legs at West Virginia University, does it follow that I do not? It is later when Descartes rephrases his answer, and so his question, in terms of “what is inseparable from my nature,” that I realized that the question was special. When he proceeds to say “I am now admitting nothing except what is necessarily true,” I finally saw that the apparently ordinary question was really a question about what is essential to my being what I am. To test what a characteristic’s being essential to some kind of thing is, I just have to consistently imagine the thing without that characteristic. If I can coherently imagine a unicorn without a horn on its forehead, then having a horn would not be essential to being a unicorn; for if it were, I could not have imagined it.
When Descartes claims to know “I am… only a thinking being,” what he says he knows is an abstract truth about his nature. And so this piece of knowledge is similar to almost all of the other things which he will subsequently find that it knows: it is a necessary truth regarding a certain kind of thing’s having a particular nature or essence.
I do not find it plausible that propositions concerning my own mental state are incorrigible to me. I do believe, however, that it is possible to make mistakes about my own beliefs and desires. I might falsely believe that I like the taste of beer, when really I hate it, but pretend to everyone including myself that I like it, so I can be one of the crowd at a party. Another example would be if my roommate knew that her boyfriend was cheating on her after...