 Although Plotinus was glad to mine Aristotle’s works for distinctions and arguments that he viewed as helpful for explicating the Platonic position, there were a number of issues on which Plotinus thought that Aristotle was simply and importantly mistaken. Perhaps the major issue concerned the nature of a first principle of all. Plotinus recognized that Aristotle agreed with Plato that (1) there must be a first principle of all; (2) that it must be unique; and (3) that it must be absolutely simple. But Aristotle erred in identifying that first principle with the Unmoved Mover, fully actual self-reflexive intellection. Plotinus did not disagree that there must be an eternal principle like the Unmoved Mover; this is what the hypostasis Intellect is. But he denied that the first principle of all could be an intellect or intellection of any sort, since intellection requires a real distinction between the thinking and the object of thinking, even if that object is the thinker itself. A real distinction indicates some sort of complexity or compositeness in the thing (a real minor distinction) or among things (a real major distinction); by contrast, in a conceptual distinction, one thing is considered from different perspectives or aspects. In the absolutely simple first principle of all, there can be no distinct elements or parts at all. In fact, the first principle of all, the Good or the One, must be beyond thinking if it is to be absolutely simple. The misguided consequence of holding this view, according to Plotinus, is that Aristotle then misconceives being such that he identifies it with substance or ousia. But for the first principle of all actually to be such a principle, it must be unlimited in the way that ousia is not. As a result, Aristotle makes many mistakes, especially in metaphysics or ontology.