Aristotle on Metaphysics(2004) - Bibotu.com

314 CRITICISM OF PLATO’S THEORY OF FORMSP2-weak. The things that we perceive through the senses arechanging in some ways (but they may also be changeless in otherways).Or it may mean:P2-strong. The things that we perceive through the senses arechanging in every way (so there is no way in which they are alsochangeless).Evidently, for the argument to be valid P2 must be understood as P2-strong, not as P2-weak. <strong>Aristotle</strong> indicates that this is how P2 is intendedby Plato and the Platonists when he says that, according to them, senseperceptiblethings (ta aisthēta) are ‘always’ flowing, by which he appears tomean not only that they are changing all the time, but that they arechanging in every way.Suppose that P2 had meant only P2-weak. In that case one may object(against the inference from P1 and P2 to C1) that explanatory knowledge,although it is of changeless things, can still be of the changing things thatwe perceive through the senses. For if these things are not changing inevery way, explanatory knowledge can be of what is changeless aboutthem, in particular their changeless essence. Indeed this appears to be<strong>Aristotle</strong>’s central objection to Plato’s argument for the separation anddistinctness of essences. For <strong>Aristotle</strong> argues that P2-strong is false and thatonly P2-weak is true. This allows him to argue, against Plato, that in spiteof the fact that sense-perceptible things are changing and that explanatoryknowledge is of changeless essences, explanatory knowledge can be ofsense-perceptible and in general of changing things. For there is somethingchangeless even about sense-perceptible and, in general, changing things,and this is their essence (see Chapter 7§5vi).It may appear to us that <strong>Aristotle</strong>’s response to Plato is eminentlyreasonable, and that obviously only P2-weak, not P2-strong, is true. But thisimpression would be precipitate. For we saw (in Chapter 7§5vi) that<strong>Aristotle</strong> is faced with a particular and pressing aporia: how can the essencebe changeless, and in particular free from generation and destruction, if itis inseparable from the changing, material thing whose essence it is, andthis thing is subject to generation and destruction? It is especially worthnoting that this is a problem for <strong>Aristotle</strong>, who argues that the essence of achanging, material thing is inseparable from that thing. It is not a problemfor Plato, who argues that essences and forms are separable and distinctfrom changing things. Indeed, it appears to be precisely this aporia that