In this commentary, Proclus address the nature of the Demiurge and shows that he is subordinate to and instrumental to the causal activity of the first principle of all, the Idea of the Good. The Demiurge is not the first principle. His role is as an irreducible instrument of the infusion of goodness into the kosmos. The Demiurge and his causal activity is set alongside the causal activity of the Living Animal, the paradigm employed by the Demiurge in order to bring intelligibility into the sensible world. Proclus here addresses the nature of the causality exercised by the Good and the intelligible world, introducing the concept of triads, which are the paradigms of efficient causal activity here below. Proclus also shows that the “traces” of intelligibility found in the Receptacle of Becoming are evidence of a sort of quasi-intelligibility, which is what occurs when intellect is missing. Thus, the hierarchical causal scope of the elements of the intelligible world is demonstrated. The ultimate causal scope of the Good or One is shown by the existence of matter that is bereft of intelligibility altogether but is indispensable for the instantiation of images of the Forms.