Rene Descartes and John Locke are both philosophers with two different views on how we obtain knowledge. Descartes believes we cannot believe our senses and begins to question existence and we cannot know what real is. John Locke believes that all knowledge comes from experience, and nothing is innate. It is argued that the way knowledge is obtained is by our senses.
Descartes begins by denying Aristotle’s teachings that all knowledge arises from the senses. According to the Stamford Encyclopedia of Philosophy (SEP), Aristotle says “There is nothing in intellect that was no previously in the senses”. Aristotle also says that as children we are naturally led by our senses in seeking befits and avoiding bodily harms. As a result, when we grow into adults we are “immersed” in the body and the senses, and so we accept the view that the senses are the basis for learning about the nature of reality. Descartes believes that human intellect is able to perceive the nature of reality through intellectual perception. According to the Stamford Encyclopedia of Philosophy Descartes says “in order to understand the fundamental truths of metaphysics we have to reject the mind from the senses and turn to out innate ideas of the essences of things such as mind, matter and infinite being.”
Descartes comes up with six meditations two of which will be explained. In Meditation I Descartes helps people withdraw from their senses. To do this you must first doubt your commonsense because it is a set of beliefs that is based on your sight, hearing, taste, smelling and touching. “in the present I have accepted as most true and certain I have learned either from the senses or through the senses but it sometimes proved to me that the senses are deceptive and it is wiser to not trust entirely to anything to which one has been deceived”(Descartes 188). He is saying that he used to rely on his senses for information and they have sometimes lied to him so he cannon trust something if it has given him false information. Descartes wonders if he could be dreaming all of his experiences since a in a dream everything can seem perfectly normal as if we are awake. He says ” I am a man and consequently I am in the habit of sleeping and in my dreams representing to myself or sometimes even less probable things, then those who are inane in their waking moments”(Descartes 188). This means since he is human he sleeps and his dreams show him doing less than probable things. He also says “I see so manifestly that there are no certain indications by which we may clearly distinguish wakefulness from sleep that I am lost in astonishment” (189), which he is saying that dreams are so real that is hard to understand the difference between being awake and being in a dream. Descartes begins to doubt nature as a whole and even begins to doubt his own body. Since man can dream that one’s body can change, he begins to doubt weather one does indeed have a body and begins to wonder about the existence of an “external world”. Descartes does however believe the Arithmetic, geometry and other sciences cannot deceive him because, two plus three will always equal five and no matter how you look at a square it will always have four sides to it. Descartes next begins to doubt his creator (god) and ask himself weather god would deceive him and says, “God has not desired that I shall be thus deceived for He is said to be supremely good”(Descartes 189) he comes to the conclusion that god is good and would not deceive him. Finally to conclude Meditations I Descartes says that not a good god but an evil genius, a demon is constantly deceiving him, he says “just as a captive who enjoys an imaginary liberty, when he begins to imagine that his liberty is but a dream, fears to awaken and conspires with these agreeable illusions” (Descartes 190) This means that we dream that everything is good and when we awaken to the reality we begin to fear and agree with the illusions.
In Descartes Meditations II he talks about the existence of god. Descartes talks about how he was persuaded that there was nothing in all the world, there was no heaven, earth, no minds, nor any bodies, likewise persuaded that I did not exist. However she says “I myself do exist since I persuaded myself of something, but there is some deceiver or other, very powerful and very cunning, whoever employs his ingenuity in deceiving me. Then without doubt I exist also if he deceives me and let him deceive me as much as he will because I can never be nothing so long as I think I am something. He is saying that since he has the ability to convince himself of something that he must exist but there is some higher figure whose main purpose is to deceive him and make him feel he is nothing however he will never be nothing because I can think he is something. (Descartes 192). This brings us to his theory, I think therefore I am. Descartes knows that he exists but exactly what is he? He believes he is a thing that thinks. He says “I believed myself to be a man, but what is a man? Shall I say a reasonable animal? Certainly not because then I have to inquire what is an animal and what is reasonable”(Descartes 192). This says he knows he is a man but doesn’t know what a man is, he would call man a reasonable animal but then he would have to figure out what is considered an animal and what is considered reasonable. “I considered myself as having a face, hands, arms, and all that systems of members composed of bones and flesh as seen in a corpse, which I designated by the name body.”I considered that I was nourished, that I walked, that I felt, that I thought. I referred all these actions to the soul.”(Descartes 192). In this he is saying he knows he has all the features of what is called a body and he has a soul since he is nourished can walk, has feelings and thoughts. “I am however a real thing that thinks and really exist, but what thing. What is a thing that thinks? It is a think which doubts, understands, affirms, denies, wills, refuses, which also imagines and feels.”(Descartes 193), In this Descartes is saying that he is a real thing and a thing that thinks and that is to doubt, understand, affirm and deny various actions or thoughts. Descartes comes to the conclusion that we exist because we think and that god exist because without him we would not exist.
John Locke’s An Essay Concerning Human Understanding states that knowledge comes from experience. This means that ideas cannot be born into our minds and we learn ideas through our own experiences. He refuses the theory of “innate ideas” or ideas that are born into us. Some men believe that there are certain understandings stamped into their minds at birth; Locke says “men barely by the use of their natural faculties may attain to all knowledge they have, without the help of any innate impressions and may arrive at certainty, without any such original notions or principles”(Locke 198). Locke is saying how man barely use their natural mental abilities may attain to all the knowledge they have without the use of their innate impressions. He thinks that mankind should have a agreed belief, “Universally agreed upon by all mankind, which therefore, they argue must need to be constant impressions which the souls of the men receive in their first beings, and which they bring into the world with them, as necessarily and really as they do inherent faculties.” (Locke 198). He is saying that all mankind must agree on certain things that are received when first brought into the world. Locke says that universal consent proves nothing innate, “drawn from universal consent, has this misfortune in it, that if it were true in matter of fact that there were certain truths wherein all mankind agreed, it would not prove them innate, if there can be any other way shown how men may come to that universal agreement in the things they do consent in, which I presume may be done.” (Locke 198). If all mankind comes up with knowledge they were born with it would not prove anything is innate because they can find another way to come up with universal consent. He fights the innate arguments “Whatsoever is, is and it is impossible for the same thing to be and not to be” have the most allowed title to be called innate however Locke believes “These have so settled reputation of maxims universally received that it will no doubt be though strange if anyone should seem to question it. Yet I take liberty to say that these propositions are so far from having a universal assent that there are great parts of mankind to whom they are not so much known. (Locke 198). In this quote Locke is saying that yes these arguments are the closes points towards being innate but there are a big part of mankind who does not know these arguments therefore they cannot be innate. One of his final points are “It is evident that all children and idiots have not the least apprehension or thought of them, and the want of that is enough to destroy that universal assent which must needs to be necessary concomitant of all innate truths, it seeming to me near a contradiction to say that there are truths imprinted on the soul which it perceived to understand not. For to imprint anything on the mind without the mind perceiving it seems to me hardly intelligible. If therefore children and idiots have souls, have minds, with those impressions upon them, they must unavoidably perceive them and know the truths. (Locke 198-199). Since children and idiots are unable to know what is considered to be innate understating that are imprinted on the mind then they are not innate and how can they be unknown. Locke believes that our minds are blank tablets and we fill those tablets with our experiences. Locke next argues the idea of sensations saying that it is constituted by nature and able to affect our senses and cause any perceptions of the mind. He goes on to say that the ideas of heat and cold, light and darkness, white and black are each two very different things which we perceive. He says that the mind comes up with ideas which he calls quality and believes there are primary and secondary qualities. Locke says we see primary qualities as an objects body and secondary qualities as properties of those objects and are the powers that produce these objects. For instance a primary quality is a table and its secondary qualities could be its brown color, or smooth touch, and hard surface etc… Locke calls this the Casual Theory of Perception. What Locke is saying in this passage is that everything we perceive has two qualities a primary and secondary. The primary is the actual object itself and the secondary are the characteristics of that object. He goes on to challenge Descartes belief of the existence of god. He says ” the knowledge of the existence of anything we can have only by perception for there being no necessary connexion of real existence with any idea a man hath in his memory nor any other existence but that of god with the existence of any particular man, no man can know he particular existence of any other being” (Locke 205). What Locke is saying is there is no proof of the existence of god and he is an idea in our head and an idea is “produced in our minds” (Locke 202). Locke says ” we talk or think of any particular sort of corporeal substances as horse, stone, etcâ€¦, though the idea we have of either of them be but the complication of collection of those several ideas of sensible qualities which we used to unite in the thing called a horse, stone, yet since we should not perceive how they should subsist alone, nor one in another, we suppose them existing in, and supported by common subject, which support we denote by the name substance, though it be clear certain we have no clear or distinct idea of that thing we suppose a support” (Locke 208). What Locke is saying is a horse or a stone have various qualities and those qualities put together gives us a horse or a stone, however is you separate those qualities you would be unable to identify them. For example a stone has a hard, sharp look and feel to it but put hard and sharp separately and there is no distinct way to picture it by itself.
John Locke has some valid points when talking about sensations how some qualities together make an object but apart they are unidentifiable, however I feel Descartes makes a stronger point to his arguments of existence, our senses can easily deceive us any to understand who we really are we need to understand where we come from and what we know to be true from what we were born with.
March 17, 2013
A Quest for Knowledge Descartes V Locke
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