Aristotle on Metaphysics(2004) - Bibotu.com

306 CRITICISM OF PLATO’S THEORY OF FORMS2Central differences between Plato’s and <strong>Aristotle</strong>’stheories of essenceWe have seen that Plato and <strong>Aristotle</strong> share the same overall aim, which isto search for the most explanatory knowledge of things, and in the firstinstance those things with which we are directly familiar from experience.They also share the same general view about how this aim is to be achieved,i.e. by supposing that things have an explanatory essence, and that we canknow their essence. The essence of a thing, for both Plato and <strong>Aristotle</strong>, iswhat the thing is simply in virtue of itself (kath’ hauto and auto kath’ hauto);and it is what we know when we know the real definition of the thing, i.e.when we know the answer to the question, ‘What is this very thing?’ Sothe essence of a thing is what explains why the thing is the determinate andwell-defined thing it is. However, they differ fundamentally over how thisessence is to be understood, and they defend very different theories ofessence. For Plato, the things with which we are directly familiar fromexperience, and in general the changing things, do not have an essence; andthe things that have an essence, and indeed are essences, are distinct fromthe changing things. For <strong>Aristotle</strong>, on the contrary, the changing thingsthemselves have an essence; indeed there is a fundamental sense in whichthey are identical with their essence. <strong>Aristotle</strong>’s criticism of Plato’s theory offorms is a criticism of Plato’s distinctive theory of essence. So let us beginwith a summary of Plato’s theory of essence and especially of those claimsin it that <strong>Aristotle</strong> rejects.To provide a summary of Plato’s theory of essence is not an easy task, forPlato’s dialogues are not straightforward or easy to interpret. On the otherhand, we may perhaps rely here on <strong>Aristotle</strong>’s representation of Plato; forhe provides a precise summary of Plato’s theory of essence and especially ofthose claims in it that he rejects. In that case, however, we run the risk ofmisrepresenting Plato; for we cannot assume that <strong>Aristotle</strong> alwaysunderstood Plato’s theory correctly or even that he always chose to presentit in the best light—there is an unmistakable element of vigorous polemicin the criticism. But without letting these problems delay us too much, letus set out a number of claims about essence, which we may with someconfidence say are characteristic not only of Plato as <strong>Aristotle</strong> understandshim, but of Plato himself.Plato’s theory of essence is above all characterized by a particular viewabout sense-perceptible and, in general, changing things: