Explication Of The Cogito In his Meditations, Rene Descartes attempts to prove the existence and reality of himself and things external to himself. In order to fulfill such a feat, Descartes decides to doubt all that he knows, for he knows not whether that can be relied upon. He doubts his knowledge for three main reasons. For one, he accounts that in dreams, many times he had thought that things external to himself were real. Also, he had heard people declare pain in limbs that they had lost long ago. After pondering these two experiences he declared, the chief and most common mistake which is to be found here consists in my judging that the ideas which are in me resemble, or conform to, things outside me (Descartes 16). These two accounts proved to him that he should doubt the existence of his own body.
Next, he realizes that even when he is awake, he cannot trust his senses. Descartes says that “the senses do sometimes deceive us when it is a question of very small and distant things” (14) A perfect example of such would be how a stick that is straight might appear bent when immersed in water, or might mistake the height and shape of distant towers. This makes him further realize that he cannot trust experience. Finally, he is then forced to question his mind, when he realizes that there might be an Evil Genius that controls his every thought. If there were an Evil Genius doing such, his thoughts would mean nothing and his questioning would mean nothing, because he is constantly being deceived.
With this in mind, he is able to stumble upon an epiphany, that the very fact that he is questioning, means that he exists. His reasoning is one that is quite logical. By questioning something, he knows that there has to be someone that does the actual action of the questioning, and if there is someone that questions, that someone must exist. It is a subject-object relationship. In order to question something, there must be something to question, therefore a questionable object exists. And in order for there to be questioning, some thinking thing, i.e.
Descartes, must be doing the questioning, therefore, he exists. Even if the Evil Genius is constantly deceiving him, that fact that he is being deceived means that he exists. For this reason, Descartes could not doubt that he was doubting, and thus was able to conclude that this proposition, I am, I exist, is necessarily true whenever it is put forward by me or conceived in my mind. (17). To completely prove his point to the skeptics he had to go further, for how could one realize that he/she is doubting? Descartes answers that this is possible through natural light- intuition. By establishing that he is a thing that, doubts, questions, thinks, affirms, denies, imagines, and perceives, through examples, he is able to prove how one could realize his/her doubting.
Descartes gives us the example of the wax that is melted, and the people on the street with coats. If the wax melts, one still perceives such as wax because the wax is merely something extended, flexible, and changeable (21). On the street, one could see coats and hats, but one determines that one is seeing people. This, like the wax, is done through judgement alone, by the intellect alone. With this, Descartes posits that an object can be grasped even when stripped of its outer form and perceived by the mind alone (21). He follows that by arguing that the awareness of one’s self is more certain than that of wax and coats, for one understands one’s self more clearly and distinctly than anything else.
If one is able to do such, than, through nature of light, one is able to realize that one is doubting. The main qualm that I have with Descartes’ argument, is with his nature of light argument, that he is only sure that he is doubting from judgements solely based on perception. In order to grasp a concept, one must do such only through perception because the body has to be doubted, so the mind must act alone. Like the wax, one can tell that it is still wax through intellect alone. This proposes that perception is the only measure of reality, and the conception of an object is independent from perception.
Therefore, if this is the case, it is impossible to have a change in perception that causes a change in conception. This argument leads Descartes’ into some trouble. For, if one sees coats and hats walking around in the street, one’s nature of light- intuition, would tell one that those things inside of them are people, because that is what we are used to seeing. So, through intellect alone, one is able to determine that those are people out on the street, yet what if that conception changes. According to Descartes, it cannot, but the thing inside the coats and hats might be trained chimpanzees walking around.
So suddenly, one realizes that the perception of the coats and hats was wrong, and that the conception changed. Therefore, just as Descartes has the perception that he is doing the doubting, because of the lack of empirical evidence and the unreliable quality of perception, through his method Descartes cannot be clearly and distinctly sure of anything. Bibliography Works Cited Descartes, Ren. MEDITATIONS ON FIRST PHILOSOPHY. 3rd ed. Trans.
Donald A. Cress. Indianapolis: Hackett Publishing Company, 1993. Philosophy Essays.