Belonging, it is said, to a rich and distinguished family, Parmenides attached himself, at any rate for a time, to the aristocratic society or brotherhood which Pythagoras had established at Croton; and accordingly one part of his system, the physical part, is apparently Pythagorean.
A new departure was taken by the Eleatic Parmenides (q.v.), who, expressly noting that, when Thales and his successors attributed to the supposed element changing qualities, they became pluralists, required that the superficial variety of nature should be strictly distinguished from its fundamental unity.
In the Parmenides reconstruction predominates over criticism - the letter of Eleaticism being here represented by Zeno, its spirit, as Plato conceived it, by Parmenides.
Its foundation is often attributed to Xenophanes of Colophon, but, although there is much in his speculations which formed part of the later Eleatic doctrine, it is probably more correct to regard Parmenides as the founder of the school.
First, whereas it has been assumed above that Xenophanes was theologian rather than philosopher, whence it would seem to follow that the philosophical doctrine of unity originated, not with him, but with Parmenides, Zeller, supposing Xenophanes to have taught, not merely the unity of God, but also the unity of Being, assigns to Parmenides no more than an exacter conception of the doctrine of the unity of Being, the justification of that doctrine, and the denial of the plurality and the mutability of things.
But, while he thus stood aloof from philosophy, Xenophanes influenced its development in two ways: first, his theological henism led the way to the philosophical henism of Parmenides and Zeno; secondly, his assertion that so-called knowledge was in reality no more than opinion taught his successors to distinguish knowledge and opinion, and to assign to each a separate province.
In short, the ordinary belief in plurality and motion seemed to him to involve fatal inconsistencies, whence he inferred that Parmenides was justified in distinguishing the mutable movable Many from the 1 See Zeller, Die Philosophic d.
The same authority says he was a pupil of Parmenides and of Heraclitus, but the statement is improbable, owing to discrepancy in dates.
In the Sophist criticism predominates over reconstruction, the Zenonian logic being turned against the Parmenides metaphysic in such a way as to show that both the one and the other need revision: see 241 D, 244 B seq., 257 B seq., 258 D.
To say that the Platonism of Plato's later years, the Platonism of the Parmenides, the Philebus and the Timaeus, is the philosophy of Parmenides enlarged and reconstituted, may perhaps seem paradoxical in the face of the severe criticism to which Eleaticism is subjected, not only in the Parmenides, but also in the Sophist.