Metaphysics H 6 and the Problem of Unity

What Aristotle's main concern is in Metaphysics H 6 has long puzzled commentators. In this paper I argued for a novel, deflationary interpretation of that chapter: Aristotle's main concern is to argue for the causeless unity of the definitions of form and of composite substance. The problem he is grappling with arises from a combination of (a) speaking about the parts of form and the parts of composite substances, and (b) the principle that parts of a whole need a unifying cause in order to be one and not many. If both form and composite particulars need a unifying cause, form cannot be primary substance, and composite substances, as composites of form and matter, cannot be true unities, but must be mere heaps of material parts which need a third unifying cause. Aristotle argues that although (a) and (b) seemingly threaten his theory of substance with incoherence, the problem can be easily solved if the unity of definitions of form and of composite substance are properly seen as causeless. In the course of clarifying and defending this reading of H6, a number of alternative interpretations are exposed and criticized.