1. RELATION OF THE ELEATIC PRINCIPLE TO THE PYTHAGOREAN.—While the Pythagoreans had made matter, in so far as it is quantity and the manifold, the basis of their philosophizing, and while in this they only abstracted from the determined elemental condition of matter, the Eleatics carry the process to its ultimate limit, and make, as the principle of their philosophy, a total abstraction from every finite determinateness, from every change and vicissitude which belongs to concrete being. While the Pythagoreans had held fast to the form of being as having existence in space and time, the Eleatics reject this, and make as their fundamental thought the negation of all exterior and posterior. Only being is, and there is no not-being, nor becoming. This being is the purely undetermined, changeless ground of all things. It is not being _in_ becoming, but it is being as exclusive of all becoming; in other words, it is pure being. Eleaticism is, therefore, Monism, in so far as it strove to carry back the manifoldness of all being to a single ultimate principle; but on the other hand it becomes Dualism, in so far as it could neither carry out its denial of concrete existence, _i. e._, the phenomenal world, nor yet derive the latter from its presupposed original ground. The phenomenal world, though it might be explained as only an empty appearance, did yet exist; and, since the sensuous perception would not ignore this, there must be allowed it, hypothetically at least, the right of existence. Its origin must be explained, even though with reservations. This contradiction of an unreconciled Dualism between being and existence, is the point where the Eleatic philosophy is at war with itself—though, in the beginning of the school—with _Xenophanes_, it does not yet appear. The principle itself, with its results, is only fully apparent in the lapse of time. It has three periods of formation, which successively appear in three successive generations. Its foundation belongs to _Xenophanes_; its systematic formation to _Parmenides_; its completion and partial dissolution to _Zeno_ and _Melissus_—the latter of whom we can pass by.