Plato, Archytas, and the other Pythagoreans divide the soul into three parts, reason, anger, and appetite, which they consider to be necessary to form the ground-work for the virtues. They assign to the soul as faculties the natural (generative) power, sensibility, imagination, locomotion, love of the good and beautiful, and last, intelligence. C. Nemesius.[363] Aristotle says, in his Physics,[364] that the soul has five faculties, the power of growth, sensation, locomotion, appetite, and understanding. But, in his Ethics, he divides the soul into two principal parts, which are rational part, and the irrational part; then Aristotle subdivides the latter into the part that is subject to reason, and the part not subject to reason. D. Jamblichus.[365] The Platonists hold different opinions. Some, like Plotinos and Porphyry, reduce to a single order and idea the different functions and faculties of life; others, like Numenius, imagine them to be opposed, as if in a struggle; while others, like Atticus and Plutarch, bring harmony out of the struggle. E. Ammonius Saccas. A. FROM NEMESIUS.[366] ON THE IMMATERIALITY OF THE SOUL. It will suffice to oppose the arguments of Ammonius, teacher of Plotinos, and those of Numenius the Pythagorean, to that of all those who claim that the soul is material. These are the reasons: "Bodies, containing nothing unchangeable, are naturally subject to change, to dissolution, and to infinite divisions. They inevitably need some principle that may contain them, that may bind and strengthen their parts; this is the unifying principle that we call soul. But if the soul also be material, however subtle be the matter of which she may be composed, what could contain the soul herself, since we have just seen that all matter needs some principle to contain it? The same process will go on continuously to infinity until we arrive at an immaterial substance." UNION OF THE SOUL AND THE BODY.