People often have very similar sensations both in dream and in reality. For …show more content…
The process of thinking whether there is not anything else proves that he exist. If he does not exist, why can he provide this question? He may be deceived by some evil genius that he mentioned above, but how these clever deceivers deceive nothing if nothing exists? Descartes concludes that he exists. How long can he exist? One will exist as long as he can think. In other words, he ascertains that he is a thinking thing. The knowledge of a thinking thing is true and indubitable. He discovers the truth and his knowledge of science and philosophy depends upon the truth. One is able to doubt the square of ten is one hundred if the fact that one plus one equal to two is doubtful. Likewise, all of knowledge will be true if they are built upon the Cogito argument. Moreover, he shows that mind is more dependable than senses by using the example of wax.
Descartes points out that the senses are not reliable by using the dreaming out argument and the evil demon argument. People attain their knowledge through seeing, hearing, smelling, and imagining, so all existed beliefs should be open to doubt. Is there anything that is certain? Descartes discovers that I think therefore I am and he uses this truth as the foundation to build a new system of knowledge and