In the antiquity, two parties argue a lot on the questions like: What is the ultimate source of knowledge? Or: How do we gain knowledge? They are rationalism and empiricism.
Rationalism states that we depend on our reason capacities to gain real knowledge, which is inborn, independent and could not be determined by human beings. The most famous rationalist, Plato, contributes to metaphysics and epistemology. He explains his theory by using the example prisoners in a cave. The conclusion is that cognition comes from the appearance of the world not the reality. According to Plato, there exist two worlds: the real world and a supernatural realm which contains the eternal and perfect Forms. Everything we get from the real world is a reflection of the supernatural hence the essence is invisible. Reason is the only way in which we get the essence of appearance.
Based on Plato’s metaphysics, Parmenides and Heraclites assert diverse opinions. Parmenides assumes that being is real and ...view middle of the document...
Hence, we are able to have access to it through the use of senses. All these knowledge derives from sensory information so we are in-formed by them. He also insists that essence is part of the real world. Therefore, it is accessible by empirical researches, not merely by using reason. What’s more, Aristotle challenges Plato’s prenatal ideas. He claims that people are born with no knowledge at all, just like a blank slate. As time passes, they get to know everything by their sense experiences. However, Aristotle does not wholly exclude the presence of reason. Although we need our senses to get to know the world, we can only manage to have knowledge of something when we find the underlying reasons and this makes the notion of causality crucial to Aristotle’s theory of knowledge. According to him, to have knowledge of a thing is to have the knowledge of four causes (the formal cause, material cause, efficient cause and final cause). In order to find the causal explanation, Aristotle introduces the syllogism--deduction, reasoning from basic principles to particular cases and induction, from particular to universal, the latter of which dismisses Plato’s recollection via anamnesis. In terms of induction, it is obvious that by simply gathering empirical data is far from enough to establish the truth of a principle, no matter how large our collection is, the universal validity still cannot be guaranteed. It is the intuitive grasp of intellect, the nous that detects the essence of an object.
Compared to Plato’s theory, we would prefer Aristotle’s. Here we provide two main reasons. First, Plato is too absolute. He thinks reason is the only source of knowledge and that essence cannot be perceived by senses, while on the contrary, Aristotle holds the view that sensory experiences constitute knowledge and more importantly, he admits the existence of reason that we discover essences by using our reason. Second, we are not quite convinced by the learning-by-recollection and the prenatal knowledge. We are suspicious of the process he drew this conclusion. Referring to the example of how the slave solved the mathematic problem, it is stated as well in the book that the slave did not figure things out himself but simply following Socrates and said yes or no. Therefore, we think Aristotle’s idea is on the overall basis superior to Plato’s.