Descartes is interested in the certainty of his existence and the existence of other people and things. Descartes' beliefs vary from those of Socrates. Descartes argues that knowledge is acquired through awareness and experience. Using this approach, Descartes moves through doubt to certainty of his existence. He asks himself various questions about the certainty of his existence and solves them through clear thought and logic. Using this method Descartes establishes doubts to be truths and by the end of the book, he has established that he does indeed exist.

In this paper, I will show how Descartes moves through doubt to certainty. I will explain how Descartes uses the cog ito, proves the existence of God and what that means to his existence. I will also discuss the general rules of truth that Descartes establishes. In the First Meditation Descartes begins to examine what is certain and what is doubtful.

Descartes wants to establish that his knowledge is certain and not doubtful. He states, ... I had accepted many false opinions as being true, and that what I had based on such insecure principles could only be most doubtful and uncertain; so that I had to undertake seriously once in my life to rid myself of all opinions I had adopted up to then, and to begin, and to begin afresh from the foundations, if I wished to establish something firm and constant in the sciences. (Descartes 95) By this Descartes means that he wishes to establish a foundation for his knowledge based on certainty instead of doubt. Descartes first looks at the senses. This is important because the senses are the first thing to cause doubt.

He focuses on the perception of things. He says that things far from him, in the distance, give him reason to doubt their certainty, while things that are close to him are indubitable and he is clear about their certainty. However, Descartes realizes that dreams pose an obstacle to his beliefs. Even up close, dreams can be indubitable.

Descartes believes that if a person has had a dream that was so intense that the person could not determine it form reality, then they have reason to doubt objects that are close to us and appear to be indubitable. In order to resolve this problem, Descartes suggests that one must examine whether they are dreaming or not. Descartes realizes that he can not rely on his senses anymore to give him dubitable truths. He turns to find something that is indubitable. Descartes tries to use science as a foundation for truth. He discards physics, astronomy, and medicine because all three of them rely upon the senses.

." ... we shall not be wrong in concluding that physics, astronomy, and medicine, and all the other sciences that depend on the consideration of composite things, are most doubtful and uncertain... ." (Descartes 98). However, Descartes finds that such things as geometry and arithmetic can be trusted because their are no senses involved.

They are based upon logic. ." ... whether I am awake or asleep, two and three added together always makes five, and a square always has four sides; and it does not seem possible that truths so apparent can be suspected of any falsity or uncertainty" (98). However, Descartes finds reason to even doubt this. The only thing that could makes these truths dubitable is through the intervention by an Evil Deceiver (God).

Descartes cannot prove that God is good and has to acknowledge that God has the power to deceive. Therefore, Descartes must doubt all things until he can prove their certainty. Descartes comes to call this doubt Universal Doubt. In the Second Meditation, Descartes examine the existence of himself.

He concludes that if he cannot prove something exists then how does he know with certainty that he exists. It is his doubt of his existence that Descartes uses to prove his existence. Descartes realizes that if he is able to doubt then he does indeed exists. He take the approach that, "I think therefore I am" to establish a certainty that he exists. This idea also known as the cog ito becomes the central point that Descartes will use for the remaining of his meditations. Descartes affirms his existence every time he thinks, doubts, or is persuaded (Descartes 103).

Descartes affirms that if there is an Evil Deceiver then Descartes must exist because in order for God to deceive, Descartes he must first exist. Although, Descartes has proved his existence he can only prove it in the mental capacity. He does not know for certain that he exists in the physical form. The only way, at this time, that Descartes can prove the existence of his body is through his senses.

He has already established that his senses are dubitable and therefore cannot tell him with certainty that his body exists. In order to get a better understanding of his relationship between his body and mind, Descartes melts a piece of wax. He observes the wax in two different states, the first in a solid form and the second in a melted form. He questions how his senses can show him two entirely different forms of the same substance; yet he knows that the substance, in both states, although completely different, is wax.

The mind was able to understand the essence of the wax. Although the senses were not entirely capable of making the connection between the two forms of wax, the senses assisted the mind in determining what the substance was. This experiment proves to be important to Descartes because he is able to make a link between the senses and the mind. Using his experiment, Descartes enters his Third Meditation using his general rule of truth that." ... all things we conceive very clearly and distinctly are true" (Descartes 113).

However, there is one flaw to his thoughts. If God is an evil deceiver than this cannot be true. Descartes proceeds to establish that God is good and does not deceive. Descartes uses three points to establish the existence God.

These points are ideas. The first one is adventitious ideas; those ideas that come from outside experiences. The second is invented ideas; those that are derived from the imagination such as sirens and chimera. The final is innate ideas; those that are within one when they are born. Descartes uses two more points to further establish that God exists. He uses the ideas of "infinite" and "perfect." These two ideas, Descartes cannot account for.

The only way for such things to come about would be from an infinite and perfect being such as God. These ideas have a direct relationship with God. In order for a finite beings such as Descartes to have a concept of infinite it must have been planted there by an infinite being such as God. Descartes concludes this idea to be true because one cannot derive the idea of infinite by negating the finite (Descartes 12....