Compare and Contrast the Philosophies of Rene Descartes and John Locke

Knowledge: Locke vs. Descartes

15 February 2009

Part 1

In this paper I will compare and contrast the philosophies of Rene Descartes and John Locke concerning how we acquire knowledge. Descartes takes the position that we gain knowledge through cognition and that our senses cannot be trusted because they deceive us. Also, he believes that we are born with some knowledge already installed in us, innate ideas. Locke, on the other hand, believes that knowledge comes from using our senses and then reflecting upon the senses that we used. I tend to agree with Locke about the use of senses to gain knowledge. I disagree with Descartes that knowledge comes from thinking and that our senses are not to be trusted. Although I agree with Locke, I do not totally agree that all knowledge comes from the use of the senses. And though I disagree with Descartes, I believe that knowledge can be attained without using the senses. In my own philosophy, I take the use of senses that Locke argues and combine that with what I call learned knowledge. I will discuss this later.

To begin, I will discuss the rationalist philosophy of Descartes. In his writhing, Meditations on First Philosophy, Descartes argues that knowledge comes from cognition, thinking. He begins by stating that even though it seems that knowledge he has gained has come through the use of his senses, he cannot trust any of those truth's because the senses can deceive. "Whatever I have up till now accepted as most true I have acquired either from the senses or through the senses. But from time to time I have found that the senses deceive, and it is prudent never to trust those who have deceived us even once." (Descartes 136). As a consequence of this notion, Descartes begins to examine the truth, or knowledge, through a system he devised called the method of doubt. To find what is true or what he can know, the object or subject has to be beyond a doubt. He goes on to investigate himself, his body with hands, eyes, fingers and such. Can he prove that anything is real or that he himself even exists? "I will then subtract anything capable of being weakened, even minimally, by these arguments now introduced, so that what is left at the end may be exactly and only what is certain and unshakable". (Descartes 139). This statement is the method of doubt.

As he evaluates himself, his body, he cannot define what he is. Any truth that he thought he before knew is gone. Even though he can see his fingers, his hand he doubts the reality of these things. He may be being tricked as he says "but rather some malicious demon of the utmost power and cunning has employed all his energies in order to deceive me." (Descartes 138). From this conclusion of being deceived he must find something in himself that is certain. He then determines that if he is capable of being tricked, then he exists. "Thinking? At last I have discovered it: thought-this alone is inseparable from me. I am, I exist- that is certain." (Descartes 140). So, thinking, this is how we arrive at knowledge? This was his belief.

But, he goes on to argue that some knowledge, some ideas are already contained within us at birth. His philosophy of innate ideas is his way of proving that in fact there is a God. He argues that he is not capable of forming the idea of a being that is infinite. Since everything, including himself has an end, how could he formulate the idea of never ending. "It is true that I have the idea of substance in me virtue of the fact that I am a substance. But this would not account for my having the idea of an infinite substance, when I am finite, unless this idea proceeded from some substance which really was infinite." (Descartes 144).

Secondly, I will discuss the empiricist philosophy of John Locke. Locke is the polar opposite of Descartes on the issue of acquiring knowledge. He believes that all knowledge and ideas come from the use of the senses. Along with sensory perceptions, he speaks of reflection. Reflection comes about when one perceives an object and then reflects upon it in his mind. To him these are the only ways of gaining knowledge. Putting these two ways of learning together he calls experience. All knowledge is gained through experience. "Our observations, employed either about external sensible objects or about the internal operations of our minds perceived and reflected on by ourselves, is that which supplies our understandings with all the materials of thinking." (Locke 150).

He goes on to break down the sensible qualities of objects into primary and secondary qualities, but for this discussion I will keep it simple. Basically, Locke explains that our only way of gaining knowledge is through the using our senses that perceive all of the qualities, such as a hot flame or cold ice, that an object has. By perceiving these qualities we know that fire can burn us and warm us depending on how we come in contact with it. We learn this through experience.

Locke addresses the issue of innate ideas that Descartes introduced to the world in a very short and direct manner. Locke basically shoots down this proposal by stating that if innate ideas are apparent, then all mankind would agree about those ideas. Since they do not, then they cannot exist. "But which is worse, this argument of universal consent, which is made use of to prove innate principles, seems to me a demonstration that there are none such, because there are none to which all mankind give an universal assent." (Locke 148).

Part 2

To begin my argument, I will start with the very origins of Descartes philosophy. How can a person deny that the senses are relevant? How would a person ever do anything? How would Descartes himself ever be able to do his writings without his senses? Do the hand and fingers not touch the pen? Do the eyes not see the words written? The thoughts may come from the mind, but the writing comes from the hand. The mind cannot write, it can not reach down and ink the letters to the paper.

The senses are a basis for knowledge. Without the senses, one could not formulate most ideas. The senses give the person the ideas that they think of when they see and object. For example, if one was to look at a book, they could not say whether it is heavy, soft, hard, hot, or cold without using the physical senses of the body. While sight is a sense, it will not tell the entire story; by touching and feeling one could determine which of the traits the book has. A person cannot determine these traits by just thinking of a book without ever having handling one. Think if people just thought