CHAPTER III

HOW ARISTOTLE AND PLATO AGREE

             15.--After having examined these points, we can easily determine wherein Plato's and Aristotle's positions on the immaterial substances agree and wherein they differ.

             In the first place, Plato and Aristotle agree on the manner of their existence. For Plato held that all lower immaterial substances are one and good by participation in the first, which is essentially one and good. Now whatever participates in something, receives that which it participates from the one from whom it participates; and to this extent that from which it participates is its cause, just as air has light which it participates from the sun which is the cause of its illumination. Therefore, according to Plato, the highest God is the reason why all immaterial substances are each one of them one and good. Aristotle, too, held this opinion because, as he himself says, "that which is most being and most truth is the cause of being and truth for all other things."

             16.--Secondly, Plato and Aristotle agree as to the condition of their nature, for both held that all such substances are completely free of matter, although not free from the composition of potency and act, for every participating being must be composed of potency and act. For that which is received as participated, must be the act of the participating substance itself. And thus, since Plato held that all substances below the highest, which is by itself one and good, are participants, they are, of necessity composed of potency and act. This must likewise be said according to Aristotle's position, for he maintained that the nature of the true and the good is attributed to act. Hence, that which is the first truth and the first good must be pure act. And whatever beings fall short of it, must have a certain admixture of potency.

             17.--Thirdly, Plato and Aristotle agree on the nature of providence. Plato held that the highest God, from the fact that He is the One itself and the Good itself, has as His property from the root nature of goodness, to have providence over all lower things; and every lower thing insofar as it participates in the goodness of the first good, likewise acts as a providence over the things which come after it, and not only of the same order but of diverse orders as well. Accordingly, the first separate intellect is a providence over the whole order of separate intellects, and each higher intellect over a lower intellect; and the whole order of separate intellects is a providence over the order of souls and the lower orders.

             Furthermore, Plato thought that this same fact could be observed among souls themselves, namely, that the highest souls of the heavens exercise a providence over all the lower souls and over the whole generation of lower bodies; and in the same way, that the higher souls exercise a providence over the lower ones, i.e., the souls of the demons over the souls of men. For the Platonists held that demons acted as mediators between us and the higher substances.

             With this view of providence, Aristotle likewise does not disagree. For he posits one separate good, acting as a providence over all things in the manner of a single commander or master under whom are diverse orders of things in such wise that the higher orders of things achieve the order of perfect providence, and hence no defect is found in them. But lower beings which are able to receive the order of a less perfect providence are open to many defects, just as in a home, the children, who perfectly share in the rule of the father, fall short either in few things or in none: whereas the actions of slaves are found to lack order in many respects. Hence among inferior bodies, failings arise in the natural order [an order] which is never found to be lacking among higher bodies. In the same way, human souls themselves frequently fall short of the understanding of the truth and of the right appetite of the true good but this is not found among the higher souls or intellects. For this reason, Plato himself posited that certain demons were good and others were wicked, as were men; whereas the gods, the intellects, and the souls of the heavens were completely without wickedness. These are the three points on which the opinion of Plato concerning the separate substances is found to be in agreement with that of Aristotle.