Philosophy was one of my favorite subjects in college, and still remains so today. And although I enjoy reading Descartes and his Meditations on First Philosophy, wherein, he proclaims his existence as well as God’s, it is odd to hear these same 17th century arguments still in use in our modern era. Many people say they just know God exists, and although I understand that this is evidence to them, it does not affect me at all. These arguments are remarkably popular, and although they cannot be disproven, they can certainly be shown to be fallacious and illogical.
In Meditations on First Philosophy, René Descartes claims that he knows he and God exist because he clearly and distinctly perceives this to be the case. He states that because he is able to think about his existence, he must exist. Descartes believes that because he is not perfect, but is able to think of a perfect thing (God), this idea must not come from him, but from God. Descartes also claims that God must exist because he has a clear and distinct perception of him. Another argument Descartes introduces as evidence of God’s existence is that it is God’s essence to exist. He claims that he can only be certain that he and God exist because he can only clearly and distinctly perceive this and this information is innate in him. Descartes’ argument about knowing that he exists because he is able to think about it, is sound. His arguments for the existence of God and for his belief that he can only know for certain that he and God exist are valid, but not true, and therefore, are not sound.
Let me explain. Descartes believes he exists because he realizes that doubting he exists is a form of thinking. If he is thinking, he is doing something, which means he must exist. If this argument is looked at as conversion, then it would not be valid, but I think it can be understood as valid this way: If (p-I think), then (q-I am doing something). If (q-I am doing something), then (r-I must exist). Therefore, if (p-I think), then (r-I must exist). This is a hypothetical syllogism and is a valid argument. It’s premises are true; therefore, it is sound.
However, Descartes also argues that God exists. One reason he believes in the existence of God is that he is imperfect, but he can think of a perfect thing (God). He claims that an idea of a perfect thing could not come from him because of his imperfection. Because of this, he believes the idea must have come from a perfect thing (God). Therefore, God must exist (Descartes, 46). This is valid, first using modus tollens and then disjunctive syllogism: If (p-I were perfect), then (q-I would not doubt). But (not q-I do doubt). Therefore, (not p-I am not perfect). (modus tollens). I can think of a perfect thing. Either (p-it comes from me) or (q-it comes from something external to me). (Not p-it does not come from me). Therefore, (q-it comes from something external to me (God). God must exist. (disjunctive syllogism). These arguments are valid in that their logical organization is not flawed; however, probably not true because their premises are probably not true; therefore, they are not sound. Descartes gives no evidence that an imperfect person cannot think of a perfect thing without an outside influence. There may be other explanations for someone thinking of a perfect thing. I can think of a perfect man, but that does not mean one exists.
Another argument Descartes uses for the existence of God is that he clearly and distinctly perceives God; therefore, he must exist. This can be understood as valid in this way: If (p-I clearly and distinctly think God exists), then (q-God does exist). And (p-I do clearly and distinctly think God exists). Therefore, (q-God does exist). (modus ponens). This may be valid, but it is not logical. Causes of his thinking may be more complex. There may be other reasons he clearly and distinctly thinks that God exists. For example, he may be insane. I may clearly and distinctly think I am Marilyn Monroe, but that does not make it true. He may just be wrong. I have thought wrong things before, but that did not make them true. Descartes’ thoughts are not necessarily facts.
Finally, Descartes argues for the existence of God by saying that it is the essence of God to exist. He states that it is impossible to think of God separate from existing (p. 90). To test the validity of this argument, we can put it in the form of a hypothetical syllogism. If (p-I cannot think of God without thinking he exists), then (q-God and existence cannot be separated). If (q-God and existence cannot be separated), then (r-God must exist). Therefore, if (p- I cannot think of God without thinking he exists), then (r-God must exist). Although this argument is valid in form, it is not sound because it contains a fallacy known as ‘begging the question.’ It is assuming what it is seeking to prove. In order for God to have the essence of existence, there is already the assumption that he exists. Because it is fallacious, it proves nothing and is not logical.
Although Descartes makes a case for his own existence, which is not terribly difficult to do, he fails to prove God exists only because he can clearly and distinctly perceive him and based on his unfounded belief that he cannot think of a perfect being without external influence. Strangely, Descartes believes everything else is to be doubted because it cannot be perceived in this same manner (p. 80). He believes that this perception is innate, but if it is innate, then why is it not innate in everyone? And even if it was, it could be caused by other influences, such as an innate evolutionary need to explain the unknown. He also believes that he can only know that he and God exist and no others, but does he not perceive that others exist as well? Perhaps, he believes that he can perceive others because he perceives himself, so it could come from within him. However, his argument is not sound because it is based on his previous assumption of God’s existence, which is based on his clear and distinct perception of him. It is also contradictory because Descartes mentions other things he clearly and distinctly perceives, things that have no reason to be only internally perceived. If Descartes removes all fallacies upon which his arguments are based, he can only be certain of his own existence, and he fails to prove God exists.
Certainly, everyone has the right to perceive, believe, and feel within his person the truth or existence of anything, and this, indeed, may be sufficient evidence for the individual who experiences this certainty within himself, but this is not a sound argument with which to convince others. Clearly, these are interesting topics of conversation and not everything felt or believed needs to be proven, or even true, for that matter, but one should not be surprised if this line of thinking fails to impress those around him. It is interesting to analyze our own thinking, and writing this makes me wonder what things I accept as true, simply based on a feeling or a perception. Probably a great deal, and that might not be such a bad thing, as long as I don’t expect others to base their beliefs on my feelings.—Christina Knowles
Descartes, René. Discourse on Method and Meditations on First Philosophy, 3rd ed. Trans. Donald A. Cress. Indiana: Hackett Publishing Co, 1993. Print
Photo: “Human-Perception.” nabeelafsar.com. Web. 12 June 2015.