In the fourth book of the Second Ennead the treatment of matter is original, and is based on comparative studies. Evil has disappeared from the horizon; and the long treatment of the controversy with the Gnostics[393] is devoted to explaining away evil as misunderstood good. Although he begins by finding fault with Stoic materialism,[394] he asserts two matters, the intelligible and the physical. Intelligible matter[395] is eternal, and possesses essence. Plotinos goes on[396] to argue for the necessity of an intelligible, as well as a physical substrate (hypokeimenon). In the next paragraph[397] Plotinos seems to undertake a historical polemic, against three traditional teachers (Empedocles, Anaxagoras, and Democritus) under whose names he was surely finding fault with their disciples: the Stoics, Numenius, and possibly such thinkers as Lucretius. Empedocles is held responsible for the view that elements are material, evidently a Stoical view. Anaxagoras is held responsible for three views, which are distinctly Numenian: that the world is a mixture,[398] that it is all in all,[399] and that it is infinite.[400] We might, in passing, notice another Plotinian contradiction in here condemning the world as mixture, approved in the former passage.[401] As to the atomism of Democritus, it is not clear with which contemporaries he was finding fault. Intelligible matter reappears[402] where we also find again the idea of doubleness of everything. As to the terms used by the way, we find the Stoic categories of Otherness or Variety[403] and Motion; the conceptual seminal logoi, and the "Koinê ousia" of matter; but in his psychology he uses "logos" and "noêsis," instead of "nous" and "phronesis," which are found in the Escorial section, and which are more Stoical. We also find the Aristotelian category of energy, or potentiality. In the very next book of the same Ennead,[404] we find another treatment of matter, on an entirely different basis, accented by a rejection of intelligible matter.[405] Here the whole basis of the treatment of matter is the Aristotelian category of "energeia" and "dunamis," or potentiality and actuality, Although we find the Stoic term hypostasis, the book seems to be more Numenian, for matter is again a positive lie, and the divinity is described by the Numenian double name[406] of Being and Essence ("ousia" and "to on"). We now come to the Escorial section.[407] This is by far the most extensive treatment of matter, and as we are chiefly interested in it in connection with its bearing the name of Numenius at the Escorial, we shall analyze it for and against this Numenian authorship, merely noting that the chief purpose is to describe the impassibility of matter, a Stoic idea. For Numenius as author we note: a. A great anxiety to preserve agreement with Plato, even to the point of stretching definitions.[408]