Note 10 — PART II.

Plato’s system of Ideas (εἴδη) consists, strictly speaking, of what we now term generalization and abstraction,—the main part of the definition real, and he seems to have constructed his theory as a mean between the Heraclitean doctrine of a perpetual flux, modified into the notion of Protagoras, πάντων μέτρον ἄνθρωπος, (which set up γίγνεσθαι instead of εἶναι,) and the Eleatic doctrine that all is one, without multiplicity, change, augmentation, or decay. He was convinced of the reality both of the permanent being or genus (οὐσία) and of the mutable γένεσις of the phenomena:—the science that contemplates these general terms is called ἡ διαλεκτικήδιαλεκτική—Dialectics. These ideas are recognized by the νόησις and διάνοια—not by the senses; and as they belong to οὐσία, they become the objects of true science or certain knowledge. Everything of this kind is an εἶδος, or general term, or quiddity. He thought, moreover, that there was a supreme standard Idea—God—in which were comprised all other subordinate Ideas, and which contained nothing whatever capable of being apprehended by the senses. This is not exactly but nearly the view taken by Ritter, ii. 264—270.