Descartes' Archimedean point is "I think, therefore I am," although the phrasing for that principle is not to be found in Meditations on First Philosophy, but in one of his earlier works. However, he arrives at the same conclusion in Meditation II, which focuses on the fact that the human mind is more easily known than the human body. In order to understand the significance of his point, which is that, if he is thinking, he must exist, it is important to understand what theories he rejects prior to that point, and the great things he discovers from that starting point. Therefore, the concept that thought equals existence is both a conclusion for Descartes and a beginning point.
             In Meditation I, Descartes begins by looking at those basic assumptions that he has taken as truths, and wondering which of those he can call into doubt. He comes to the conclusion that he has to cease believing in these assumptions, if he can find a reason to doubt is present opinions. Instead of seeking to demolish each of these individual opinions, Descartes decides that he can call them all into doubt if he can doubt their basic foundations and principles. Therefore, he asks himself how he came to learn of the assumptions he has equated with truth. He comes to the conclusion that he learned these truths through his senses. Though he acknowledges that his senses can deceive him and that insane people are frequently deceived by their senses, he comes to the overall conclusion that generally ones senses relay true information. However, he believes that it might be impossible to discern between actual sensory experiences and remembered or imagined experiences, such as those one would have in a dream. Therefore, he concludes that he cannot doubt the basic elemental units of sensory experience, like shape or size. Likewise, he believes that studies of simple things, like arithmetic cannot be doubted, while studies of complicated, c...