Ontological Differences: Being and Substance in Book V of the Metaphysics

Aristotle’s discussions, in Metaphysics Delta 7 and 8, of things designated by the terms we translate ‘being’ and ‘substance’ are revealing in several respects. The discussion in chapter 7 reveals the centrality in his thinking of the distinction between in itself and accidental being, a distinction different from that between substance and the other categories. The discussion in chapter 8 in turn reveals not only two related criteria for calling things substance, but a distinction as well between entities that are called substances and the substance being which is the principle of their being so called