Published online by Cambridge University Press: 30 January 2009
Those who examine Plato's theory of forms have from Aristotle onwards tended to interpret it as a theory of universals. Enough in the dialogues appears to support such an interpretation for it not to be entirely wrongheaded. Nevertheless, the conception of forms as universals or as the meanings of general terms produces a baffled incredulity when we consider some of the things that Plato has to say about them. It would be outlandish enough anyway to be told that a universal is an object; it becomes positively outrageous when we are informed furthermore that the object which is the universal being a so-and-so is itself a very superior so-and-so, existing separate from and independent of the particulars it characterizes and causing them to have the nature that they do. Could Plato have seriously thought and meant things so foolish? I doubt it, for there is a more charitable, less Aristotelian, way to interpret what Plato says about forms. This is the way suggested by Eudoxus and those others who apparently drew on Anaxagoras’ theoryof the homoiomeries in the exposition of Plato: a Platonic form is like an Anaxagorean stuff and accounts for the character of a particular ‘as white does, by being mixed with the white thing’ (Aristotle, Metaphysics 991314–19, 1079–8–23). In this paper I wish to build on Eudoxus’ suggestion and show how all the most troubling contentions that Plato makes about forms turn out to be either true or at least quite plausible if we suppose that forms are meant, not as universals, but as chemical elements instead. Plato's theory of forms is not a grotesque misunderstanding of universals; it is a sober, intelligent, and largely true account of the elemental stuffs from which the world is made.
1 I take the term ‘real change’ from Geach and I accept his distinction between it and what he calls ‘Cambridge change’. See e.g. Geach, P. T., Truth, Love and Immortality (London:Hutchinson, 1979), 90–92. My criterion is not circular:when it speaks of an alteration in the arrangement of spatial parts this can beadequately glossed as a Cambridge alteration.Google Scholar
2 See Brian Ellis, , Rational Belief Systems(Oxford:Basil Blackwell, 1979Google Scholar), 1–5, for a trenchant statement of the claim that every scientific law is true only of idealized entities. Plato would, I think, concur with this generalization, if we may judge by the derogatory remarks in Republic 529c ff. on the heavenly bodies we perceive and on how they do not live up exactly to the laws of mathematical astronomy.
3 According to Nelson, Goodman, Fact, Fiction and Forecast, 2nd edn (Indianapolis and New York:Bobbs-Merrill, 1965Google Scholar), 74, this term ‘applies to all things examined before t just in case they are green but to other things just in case they are blue’.
4 4 This and the preceding paragraph draw heavily upon the essay‘Natural Kinds’ in W. V. Quine, Ontological Relativity and Other Essays(New York and London:Columbia University Press, 1969), 114–138Google Scholar.
5 For judicious remarks on this topic see T. W. Bestor, ‘Common Properties and Eponymy in Plato’, Philosophical Quarterly 28 (1978), 189–207.
6 See e.g. Aristotle Physics 185D25 ff. and Simplicius ad loc.
7 ‘Incomplete Predicates and Two-World Theory of the Phaedo’, Phronesis 17 (1972), 61–79.
8 Misnamed for two reasons: because as Plato presents it the argument concerns the form of big; and because he hesitated, on independent grounds, to posit a form of man (Parmenides 130CI-4). The misnomer seems to stem from Aristotle, e.g. Metaphysics 990b 17.
9 9 The point merits stress in view of a very natural tendency to think otherwise. Thus according to F. C. White, ‘Plato on Naming-After’, Philosophical Quarterly 29 (1979), 255–259, at p. 257, ‘It is resemblance and the implied sharing of properties which gives rise to the regress’ (my italics). See however the seventh of Nelson Goodman's ‘Seven Strictures on Similarity’ in Experience and Theory, Lawrence Foster and J. W. Swanson (eds) (London: Duckworth, 1970), 19–29.
10 An earlier version of this paper was read at Downing College, Cambridge. I have benefited greatly from discussing these topics with G. E. M. Anscombe, M. F. Burnyeat, W. R. Jordan, S. A. R. Makin, and G. E. L. Owen, of whom perhaps none agreed with all my conclusions. Ultimately the paper stems from a talk I gave at the Victoria University of Wellington during a most pleasant visit there in July 1980.