The next treatment of matter in the Fourth Ennead, is semi-stoical.[431] The opposite aspects of the Universe appear again as "phronesis" and "phusis." We find here the Stoic doing and suffering, and[432] hypostasis. Nevertheless, the chief process illustrated is still the Platonic image reproduced less and less clearly in successively more degraded spheres of being. Plotinos seems to put himself out of the Numenian sphere of thought, referring to it in abstract historical manner, as belonging to the successors of Pythagoras and Pherecydes, who treated of matter as the element that distinguished objects in the intelligible world. The last treatment of matter[433] seems to have reached the extreme distance of Numenianism. Instead of a dualism, with matter an original, positive principle, Plotinos closes his discussion by stating that perhaps form and matter may not come from the same origin, as there is some difference between them. He has just said that Being is common to both form and matter, as to quality, though not as to quantity. A little above this he insists that matter is not something original, as it is later than many earthly, and than all intelligible objects. As to the Numenian double name of the Divinity, Being and Essence, he had taken from Aristotelianism the conceptions of "energeia" and "dunamis," and added them as the supreme hypostasis, so as to form in theological dialect the triad he, following Numenius and Plato, had always asserted cosmologically (good, intellect, and soul): "The developed energy[434] assumes hypostasis, as if from a great, nay, as from the greatest hypostasis of all; and so it joins Essence and Being." Reviewing these various treatments of matter we might call the first[435] Numenian; the next[436] Platonic (as most independent, and historically treated); the next[437] as Aristotelian; the Escorial Section as semi-Stoic;[438] as also another short notice.[439] The last treatment of matter, in vi. 3.7, is fully Stoic, in its denial of the evil of matter. How then shall we explain these differences? Chiefly by studying the periods in which they are written, and which they therefore explain. * * * * *