Alicia Moody
I find Aristotle's epistemology to be far more balanced. While he certainly prefers inductive arguments when he can make them, he isn't reluctant to argue deductively from a priori principles that we might not agree with. In fact another popular characterization of Aristotle is that his philosophy held back science by insisting on claims that were not evident in nature. Some of these claim could easily have been rejected with very straightforward experiments.
Empiricism and its opposite Rationalism are positions about the nature and origin of knowledge.
Empiricists say that knowledge comes from experience.
Rationalism says that we have at least some knowledge innately (prior to experience).
However, Aristotle isn't exactly a proponent of natural science in the sense that we think of the natural sciences today because he hasn't got the idea of an experiment. Aristotle's scientific method does depend upon observation. Rationalists claim that we have a priori knowledge of synthetic propositions, i.e. knowledge of matters of fact that does not depend upon sense experience. They argue that there are two key ways in which we gain such knowledg. we know certain truths innately, and we have a form of rational ‘intuition’ or ‘insight’ which enables us to grasp certain truths intellectually. Descartes is a rationalist in both these ways. Many rationalists add that the synthetic a priori knowledge we gain through reason or innately cannot be arrived at in any other way.
They may also argue that is superior, for example by being more certain, to the knowledge or beliefs we gain through the senses. Descartes’ theory of clear and distinct ideas is his account of rational ‘intuition’. At the heart of the idea of rational intuition is the view that you can discover the truth of a claim just by thinking about it. Descartes defends by reasoning, and we are supposed to recognize that it is true just by considering it. Descartes then goes on to argue that he, as a mind, can exist without having a body. It is therefore possible for minds to exist without bodies. secondly, Descartes believes he can establish by a priori reasoning. How do we know about bodies, physical objects? First, how do we know what physical objects are, i.e. what are we talking about? We might say we discover their nature through sense experience. Descartes argues that sense experience gives us only a confused idea of physical objects. We discover what physical objects are by analyzing our concept of a physical object to exist in space, with a size, shape and location. So Descartes must secure our knowledge of the external world. So there must really be an external world. Descartes argues that God has set us up to learn from nature. Nature teaches us through sensation that we have bodies, and through perception that there are other bodies. This can’t simply be the abstract truth that a physical world exists. It must the stronger claim that, in many of our experiences, we are actually confronted with physical objects. Descartes does not claim that the external world is as we commonly think it is. His argument has established that the physical world exists and is an extended world.
INNATE IDEAS In the arguments regarding physical objects and God, Descartes takes the concepts, or ideas, of PHYSICAL OBJECT and GOD for granted. (When referring to a concept, I put the word in capital letters.) Where do these concepts come from? In his Trademark argument for the existence of God, he says there are three possible sources for a concept: that we have invented it (it is ‘fictitious’), that it derives from something outside the mind (it is ‘adventitious’), or that it is innate. By ‘innate’, he doesn’t mean we have it from the birth in the sense that a baby can think using this concept. It would be very strange in babies could think about God but didn’t yet have a concept of power or reality or love! Innate ideas are ideas that the mind has certain capacities to use, and which can’t be explained by our experience. To defend his claim that these ideas (of GOD and PHYSICAL OBJECT) are innate, Descartes needs to show that they cannot be explained by sense experience. And this is what his arguments try to do. Sense experience cannot tell us the essential nature of physical objects; it is an idea that we must use the intellect to analyse. How did it come to be part of the intellect? It is innate. Likewise with GOD.
Descartes, using reasoning
His arguments are supposed to be deductive, and his premises established by rational intuition.
If intuition and deductive reasoning do not give us knowledge, then his rationalism is in trouble. Before we become skeptical about intuition and reasoning, we should ask this: how have philosophers come up with objections to Descartes? It certainly isn’t by using sense experience! So the objections themselves use the same kind of reasoning as Descartes. Only better reasoning, we hope. The objections cannot be objections to the way Descartes reasoned, only objections to the conclusions he drew. Descartes’ theory of clear and distinct ideas is correct.
Hume would argue that we can only perceive the truth of a claim just by thinking about it when that claim is analytic. Our ability to tell that it is truth is not about insight; it is simply because the claim is made true by the meanings of the words it contains. On this view, one reason Descartes’ arguments fail is because many of his ‘clear and distinct’ ideas are not analytic, but contain assumption.
Plato believed that the physical world around us is not real; it is constantly changing and thus you can never say what it really is. There is a world of ideas which is a world of unchanging and absolute truth. This is reality for Plato. Does such a world exist independent of human minds? Plato thought it did, and whenever we grasp an idea, or see something with our mind's eye, we are using our mind to conceive of something in the ideal world. There are a number of proofs of this ideal world. The concepts of geometry, such as the concept of a circle, which is a line equidistant from a point, is something which does not exist in the physical world. All physical circles, such as wheels, drawings, etc. are not perfectly round. Yet our mind has the concept of a perfect circle. Since this concept could not come from the physical world, it must come from an ideal world. Another proof is that from moral perfection. We can conceive of a morally perfect person, even though the people we know around us are not morally perfect. So where does someone get this idea of moral perfection? Since it could not have been obtained from the world around us, it must have come from an ideal world. Platonism has been an extremely influential philosophy down through the centuries.- Omonia Vinieris (2002)
Skeptic Idealism- starts with the thought that there is no proof that there are material objects outside of thought. Problematic idealism- is the belief held by Descartes where we can only hold one empirical truth, which is that I exist. Since all that we think we perceive through our senses that gives us evidence of a universe beyond our own mind is evidence which exists in our mind there is a problem with verifying anything outside of the realm of thought.