A neglected causal principle of Aristotle
Keywords: Humanities and Sciences.
Philosophy.

My subject is an influential but puzzling principle about causality found in Aristotle: the cause of some object's having a property must itself have that property. In the first part of the dissertation (Chapter 1), I uncover the proper formulation and justification for this principle. In the second part (Chapters 2--4), I give a new reading of Metaphysics Z.7--9 that yields insight into the principle's role in Aristotle's thought. In Chapter 1, I lay out a detailed interpretation of Aristotle's version of this principle. I show that the stock objections arise from a failure to observe two key distinctions that can be shown to be genuinely Aristotelian and which give Aristotle considerable flexibility in applying the principle. The first of these is the distinction between a form and that form's mode of instantiation. The housebuilder, for instance, and the bricks and mortar both have the form of a house, but in different modes. The second distinction is that between more and less perfect modes of having a form, as the mature oak has the oak-form in a more perfect way than the acorn. Reflection on these distinctions and Aristotle's use of them suggests a partition of our principle into two, which I dub direct and indirect. The former governs immediate causal connections and only requires that the cause have the effected form in some mode or other, the second governs global chains of causality and requires that the ultimate cause possess the form in a fully actual mode. In Chapters 2--4, I give a careful and unified reading of Metaphysics Z.7--9. For it is here that Aristotle comes closest to giving this causal principle an extended discussion. Unfortunately, these chapters have frequently been misread by those who see them as intrusive to the argument of Met. Z or disunified. I restore both internal unity and a place within Z's overall argument. Chapter 2 clarifies the second half of Z.8, which, I argue, contains the main argument of Z.7--9. In fact, it consists of two arguments, each aimed at disarming the Platonists' contention that we must appeal to a Form to account for generation. Chapter 3 then shows how Z.7 and the first half of Z.8 carefully prepare the ground for these twin arguments. They do so in two ways: first, by giving an analysis of generation on which both form and matter can be seen to preexist the thing generated as immanent principles; second, by arguing that, properly, the thing generated is always the composite of matter and form. Each of these results supports one of the two arguments discussed in Chapter 2. Finally, Chapter 4 shows how Z.9 completes the earlier treatment of coming-to-be and pre-empts objections to the argument of Z.8 that would appeal either to cases of spontaneous generation or to accidental coming-to-be. Against the former, Aristotle maintains that even in spontaneous generation, the form must pre-exist, though in a lower degree of actuality, which he here expresses by saying the subject of change possesses a part of the form. Against the latter, Aristotle maintains that, because of their lesser ontological status, accidents may be caused, not by other, similar accidents, but immediately by substances