Michael Vernon Wedin

Aristotle claims in Metaphysics Z.17 that form is both a cause and principle of c‐substances. In this chapter, Wedin argues that the explanatory, or causal, role of form is in the background of the entire discussion, and indeed directs much of the argumentation of Metaphysics Zeta. Form is the cause of some matter being a unity and not a heap, because form alone explains how the material parts of a thing are united in a single whole. Wedin draws together the main results of the preceding investigation of Zeta—that form is essence, that form must not contain matter or actual parts, and that form must not be a certain kind of universal—and he argues that these constraints on form are designed to serve the explanatory role that Aristotle explicitly gives to form in Z.17. Wedin emphasizes that the notions isolated in the examination of the earlier chapters, such as the purity of form, weak proscription, and dual complexity, each contribute to the account of form as the explanatory principle of c‐substance.

Wedin offers an interpretation of Metaphysics Zeta 13, a very important and difficult chapter, where Aristotle apparently denies that substance is a universal, having, on most accounts, already claimed that form is substance, and that form is a universal. This interpretation of the argument of Z.13, Wedin argues, threatens the possibility of attaining a definition of substance, and places in doubt what has gone before in the treatise. According to Wedin, what Aristotle is concerned with in Z.13 is not the denial that substance is a universal but rather with the denial that anything predicated universally of a c‐substance is the substance‐of the c‐substance, which Wedin calls ‘Weak proscription’. In Wedin's account of Z.13, then, Aristotle is continuing to pursue issues first raised in Z.10–11 that have to do with the relations between form and definition, and form and the universal. Wedin also argues that the dilemma at the conclusion of Z.13, regarding the definability of substance, is resolved in Z.16, with the notion of ‘Dual Complexity’, according to which the parts of a form exist potentially in the form, just as the parts of the c‐substance exist potentially in the c‐substance.

Wedin's main point in this book is that the question of Metaphysics Zeta, ‘what is substance?’, should be understood as the question, ‘what is the substance of c‐substances?’. In other words, in virtue of what are the substances of the Categories the sort of things they are—in virtue of what do they have the central, salient features mentioned but not explained in the Categories? Aristotle's answer is that it is in virtue of a structural component of the c‐substance—the form: form, then, is primary substance, but this primacy is explanatory and not ontological. Thus, in Zeta, c‐substances are subjected to hylomorphic analysis, i.e. in terms of form and matter, two entities that are not even mentioned in the Categories: for Wedin this shows that Aristotle in the Categories has no interest in the structure of primary substances, because it is irrelevant to the purpose of the treatise. Hence, the treatises are complementary because ontological primacy is given to c‐substances, and explanatory primacy to their forms.

It is argued that Wittgenstein did not abandon his tractarian position because he was of the opinion that the Tractatus suffered from an intemal incoherence inherited from the incompatibility of the thesis of mutual independence of elementary propositions and the picture theory of the proposition or an incoherent notion of the elementary proposition itself. In the way suggested, TLP provides no opportunity for such concems to arise, for the inner sub-surface structure of a proposition cannot cause conflict with MI. It rather was the sub-surface nature of elementary propositions itself - a feature fundamental to the Tractatus as a whole - Wittgenstein came to be dissatisfied with and gave up in favour of a new notion of elementary proposition.

Wedin considers the relation between the ontological commitment in the Categories and the semantical theory of underlying ontological configurations for standard categorical statements. According to Wedin, Aristotle's fourfold division of beings, which divides things according to whether they are, or are not, said of, and/or present in a subject, is a meta‐ontology that is concerned with beings per se, i.e. the fundamental things that are. Wedin explains that the primacy of c‐substance involves an asymmetry in the relation between c‐substance and everything else, or between the substantial and the nonsubstantial. This is because there is an ontological dependence of non‐substances, and also of secondary substances, on substances: everything is either said of, or in, primary substance. The argument of this chapter, then, is that the world of the Categories is a world of individuals: all ontological relations needed for semantics can be accommodated by appeal to individuals only.