Durand of St.-Pourçain’s Moderate Reductionism about Hylomorphic Composites in advance

According to a standard interpretation of Aristotle, a material substance, like a dog, is a hylomorphic composite of matter and form, its “essential” parts. Is such a composite some thing in addition to its essential parts as united? The moderate reductionist says “no,” whereas the anti-reductionist says “yes.” In this paper, I will clarify and defend Durand of St.-Pourçain’s surprisingly influential version of moderate reductionism, according to which hylomorphic composites are nothing over and above their essential parts and the union of those parts, where this union is explained by the presence of two modes: a mode of inherence on the side of form and a mode of substanding on the side of matter.