Abstract
One of the issues that deeply interested the philosophers of late antiquity, the Ancient Greek Commentators, concerns the priority of substances. While questions concerning ontological priority have recently attracted attention in Aristotelian scholarship and contemporary metaphysics, the Commentators’ discussions have not yet received the attention they deserve. My aim is to start to fill in this gap, by focusing on John Philoponus’s account of the priority of substances in his commentary on Aristotle’s "Categories". In particular, I aim to show how Philoponus develops and defends the view that, while particular substances enjoy priority over accidents and concepts (“universals after the many”), they do not enjoy priority over all other things. Rather, a certain type of universal substance (“universals prior to the many”) enjoys priority over particulars.