Aristotle on Metaphysics(2004) - Bibotu.com

304 CRITICISM OF PLATO’S THEORY OF FORMSand distinct from changing things. So he argues that his theory of essencesas separate and distinct forms is necessary to ensure the possibility ofexplanatory knowledge. <strong>Aristotle</strong> summarizes this Platonic argument inMetaphysics III. 4, when he sets out some basic puzzles or aporiai that Platoraised. Thus he says, reporting a basic Platonic aporia:For if there is not something besides [para] the particulars [i.e. thechanging things], but the particulars are indefinite [apeira], how is itpossible to attain explanatory knowledge [epistēmē] of things thatare indefinite? For we know any thing precisely in so far as it is asingle thing and the same thing [i.e. in so far as it has an essence ordepends on something that has an essence] and in so far assomething universal belongs to it.(999 a 26–29)And again:How will there be explanatory knowledge [epistēmē], if there is notsome one thing over [and above] all the things [i.e. all the changingthings]?(999 b 26–27)The first passage is of particular interest also because it indicates that<strong>Aristotle</strong> uses the term ‘besides’ or ‘over and above’ (para) to indicate thedistinctness of Plato’s forms (see §4 of this chapter). But a particularlyclear version of this Platonic argument, as it was understood by <strong>Aristotle</strong>,for the view that there are separate and distinct essences and forms, isrecorded by the later commentator on <strong>Aristotle</strong>, Alexander of Aphrodisias(second to third century AD):Further, the things the sciences are sciences of, these things are. Andthe sciences are of some other things besides [para] the particulars[i.e. the changing things]; for these [the particulars] are indefinite[apeira] and indeterminate [aorista], whereas the sciences are ofdeterminate things [hōrismena, i.e. things that have essences and areessences]. Therefore there are some things besides [para] theparticulars, and these things are the ideas.(Peri Ideōn/On Ideas, 79. 8–11; trans. G.Fine, but comments added)This is perhaps Plato’s main reason for thinking that there are essences andthat essences are separate and distinct from changing things. The reasoning