On Ideas: Aristotle’s Criticism of Plato’s Theory of Forms. – book reviews
Victor Caston
It is one of our great misfortunes that Aristotle’s On Ideas – a searing polemic against Plato’s theory of forms – is no longer extant. In it, Aristotle appears to have elaborated and criticized a number of arguments for the existence of Platonic forms, arguments which recall, but do not replicate, those we have in the dialogues. His critique is trenchant: if, per impossibile, the arguments established$what they claimed, they would also produce results intolerable to Platonists (including the celebrated Third Man regress); but in fact, Aristotle argues, if they establish anything, it is the existence of his own brand of universals and not Platonic forms. On Ideas thus records one of the most legendary confrontations in the history of metaphysics on a topic still debated today. What has survived merits the closest consideration.
Most of what we know comes from a commentary on Aristotle’s Metaphysics by Alexander of Aphrodisias (2nd-3rd century C.E.), who recounts a long string of arguments from On Ideas in order to amplify the meagre summary Aristotle recites in Metaph. A.9. Alexander’s report has been the focus of much debate in this century, especially since the work of Cherniss and Owen; but in the last fifteen years no one has done more to improve our understanding of it than Gail Fine. In a series of much read articles, she has already analysed many of these arguments in close detail, testing each of Aristotle’s criticisms against the most exacting standards and asking whether Plato is really subject to them. Now she has assembled these pieces together with much new work. The result is the first book-length treatment of Aristotle’s On Ideas to appear in English, and one which is unparalleled in both the detail and the calibre of its logical analysis. Her work gains tremendously from being published in this format: she is able to examine complex issues in greater depth and pursue systematic interconnections without redundancy. Many of her interpretations are controversial. But they are developed with exemplary rigour and circumspection: there are few objections to her views that she has not somewhere anticipated in her presentation. All of her interpretations aim, moreover, to show Plato and Aristotle at their philosophical best.
Although the title suggests a more general scope, Fine in fact limits herself to the first five arguments Alexander reports. She treats them throughout as though they constitute the whole of Book 1, even though Alexander (much like Aristotle in Metaph. A.9) proceeds immediately from the fifth argument to arguments about first principles and from there to Eudoxus’ theory of forms, all of which Fine accepts as genuine and belonging to On Ideas (n. 24, pp. 256-7). She assigns all of this later material to Book 2 instead (pp. viii, 1) without discussion or argument. This division is a little too convenient. It gives her treatment an appearance of completeness; it also helps shield her central claim that Book 1 possesses a “neatly dilemmatic” structure (p. 27; see below). But there is little evidence to back it up. Alexander says at In Metaph. 79.3-4 that the first argument, the Argument from Sciences, can be found in Book 1 of On Ideas, and he says at In Metaph. 98.21-22 that Aristotle’s criticisms of Eudoxus can be found in Book 2. This entails nothing, however, about the location of the intervening arguments. In fact, Alexander states at In Metaph. 85.11 that Aristotle discusses the fifth argument, which introduces the Third Man, in the fourth book of On Ideas. Even if we emend ‘fourth’ to read ‘first’, as Fine does (n. 32, p. 244), the placement of the other arguments, especially those concerning first principles, is an open question and so, consequently, is the structure of Book 1.
Fine begins with a close literal translation of the first five arguments (based on Harlfinger’s text with supplements), together with introductory discussions of the treatise, the problem of universals, and Plato’s central concerns (Chs. 1-4); these are then followed by detailed analyses of the Arguments from the Sciences (Ch. 5-7), the One over Many Argument (Ch. 8), the Object of Thought Argument (Ch. 9), the Argument from Relatives (Chs. 10-13), and what she calls the “Accurate One over Many Argument,” which leads to the Third Man regress (Chs. 14-16). Less than a third of the book’s pages derive directly from previously published work, and there are important (if subtle) revisions. Aristotle, for example, is treated more charitably in these pages. Although his arguments do not trap Plato, in Fine’s opinion, Aristotle has not misread him either. Rather, he issues his arguments polemically as a challenge to Plato to disambiguate key terms, supply tacit assumptions, and clarify various commitments – much as Fine does herself in this book, one might add. Many traditional Platonic themes, such as his preoccupation with change and the imperfection of the sensible world, are treated quite fully; several tangential topics, such as whether Plato accepted forms of artefacts or whether there was an Academic theory of categories, are even given separate chapters.
In what remains, I will turn to what I consider the most significant difficulty in a book excellent in other respects. One of Fine’s central claims is that the first book of On Ideas exhibits a tight logical structure: whereas the first three arguments for the existence of Forms are invalid, the two subsequent ones (which Aristotle refers to as “more accurate”) are valid, but unsound. The three “less accurate” arguments are, nevertheless, valid arguments for the existence of Aristotelian universals. Aristotle thus poses a dilemma for the Platonist: either his arguments imply what Aristotle wants or they prove nothing at all. On this reading, the distinction between the “more” and “less accurate” arguments is quite elegant, and Fine appeals to it extensively to gain philosophical leverage over the texts. It undergirds her entire approach, guiding and constraining the details of her interpretations throughout. But it is doubtful whether it will work.
In order to see whether an argument for the existence of Platonic forms is valid, we must have a clear criterion of what constitutes such a form. Fine takes the target of On Ideas to be Plato’s middle dialogues (p. 35), and forms in this period are not merely universals, on her view, but also eternal, nonsensible, separate, perfect paradigms that serve as the basic objects of knowledge (Ch. 4 passim). It should not be surprising that the “less accurate” arguments, none of which is very long, fail to generate all of these characteristics. But, as Fine now acknowledges (p. 27), neither do the “more accurate” arguments: on her view, the Argument from Relatives argues only for paradigmatic universals, while the one which introduces the Third Man argues only for separate universals. If Aristotle takes these to be valid arguments for Platonic forms, then he would have to assume that being either a paradigmatic or a separate universal is sufficient for being a Platonic form. On Fine’s interpretation, though, even this will not be enough, since she takes Aristotle to be committed to “weak paradigmatism” as well (pp. 63, 69; cf. p. 53). Accordingly, she conjectures that, for Aristotle. a universal F is a Platonic form if (and, she adds, only if) F is either a perfect paradigm or separate (p. 27). Both of the “more accurate” arguments validly argue for this disjunction in Fine’s view, while none of the “less accurate” ones does.
Fine claims, for example, that the argument which introduces the Third Man is a valid argument for separate universals (p. 200). But that argument does not draw any conclusion about the existence of separate universals; on the contrary, it assumes that whatever is predicated of many things is separated from them (84.23-24). If its author did infer the existence of separate universals, then it seems he would have done so only by begging the question, something Aristotle regards as a failure to demonstrate (APr. II.16, Top. VIII. 13). Indeed, Aristotle would not consider such an argument to be even formally a deduction (sullogismos), which requires a conclusion distinct from its premises (APr. I.1, 24b18-20). Fine defends her interpretation (p. 200) on the grounds that the separation assumption in question does not specify being separate from particulars; and the latter can be deduced validly (if trivially) from the separation assumption in the text. But this surely puts too nice a point on it. Aristotle does not ever draw this inference himself, much less explicitly distinguish between two kinds of separation. Similar lacunae typically excuse Plato from being committed to various arguments in Fine’s view; the same standards should be applied here. But if they are, then this argument is not a “more accurate” argument in the way Fine says it is.
Nor are the “less accurate” arguments quite so badly off as she suggests. The first Argument from the Sciences, like the “more accurate” Argument from Relatives, is a valid argument for paradigmatic universals on Fine’s view; but, she claims, only the latter is a valid argument for perfect paradigms, and this is required on her interpretation to distinguish Platonic forms from Aristotelian universals (pp. 155, 157-9). None of these arguments, however, including the Argument from Relatives, mention perfection in their conclusions – the inference to perfection is one we must supply. Yet the same can be done for the second Argument from the Sciences, which argues for universals on the grounds that they, unlike sensibles, are not “indeterminate” (ahorista). Fine herself takes this to be equivalent to saying that these universals are free from what she calls the “broad” compresence of opposites (p. 100); and on her view, Plato takes such freedom to be a kind of perfection (n. 31, pp. 298-9). If, then, we take the first and second Arguments from the Sciences to be linked, they provide just as valid an argument for perfect paradigmatic universals as the “more accurate” Argument from Relatives. The former constitute a valid argument for paradigms that are free of indeterminacy, the latter for paradigms that are properly F (kurios); in both cases, it is equally left to us to make the connection with perfection. The “less accurate” Object of Thought Argument, in contrast, is a valid argument for separate universals as it stands, if the second premise is read as saying “the same thought remains, even when all the Fs have perished” (Fine apparently reads phtharenton touton at 81.27 distributively as “when any given F has perished”, p. 120, though this seems strained). But if so, then it follows that the universals it argues for can exist at a time when none of their instances do (contra n. 28, p. 312); and that is as much separation on Fine’s interpretation as Plato is ever clearly committed to (Tim. 27d-31 a), as well as being something which Aristotle rejects (Categ. 11, 14a6-10).
Finally, we may ask whether Aristotle considers the arguments concerning first principles, which Fine does not discuss, to be “more accurate” arguments. Neither Aristotle nor Alexander tells us how many “more accurate” arguments there are; and the arguments concerning first principles are presented immediately after the “more accurate” Argument from Relatives and the Argument introducing the Third Man. Yet these later arguments do not appear to be “more accurate” in the way Fine’s interpretation demands. It is therefore important to her interpretation that Book 1 ends with the Argument introducing the Third Man. But this, as we have seen earlier, is open to question.
There is no need to straitjacket our interpretations by insisting that Alexander’s exact words constitute valid arguments on their own. Even the “more accurate” arguments require charitable reconstruction, and by this standard the “less accurate” arguments would fare better than Fine suggests. But that only means that more remains to be said about Aristotle’s On Ideas. And Gall Fine has given stimulus to this discussion of the most valuable kind: a detailed, systematic, and controversial view. The quality of her arguments ensures that this book will pose a challenge to interpretations for many years to come.
VICTOR CASTON Department of Philosophy Brown University 54 College St. Providence, RI 02912 USA
COPYRIGHT 1995 Oxford University Press
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