To the Eleatic school, founded by Xenophanes, belong Parmenides, Melissus the Samian, Zeno, and Heraclitus of Ephesus. All these were thinkers remarkable for courage and subtlety. The main metaphysical doctrines of this school approach, in many respects, to those that have been familiar to modern speculators. Their predecessors argued, as the basis of their system, from experience of the outward world, and the evidence of the senses; the Eleatic school, on the contrary, commenced their system from the reality of ideas, and thence argued on the reality of external objects; experience with them was but a show and an appearance; knowledge was not in things without, but in the mind; they were the founders of idealism. With respect to the Deity, they imagined the whole universe filled with it--God was ALL IN ALL. Such, though each philosopher varied the system in detail, were the main metaphysical dogmas of the Eleatic school. Its masters were high-wrought, subtle, and religious thinkers; but their doctrines were based upon a theory that necessarily led to parodox and mysticism; and finally conduced to the most dangerous of all the ancient sects--that of the sophists. We may here observe, that the spirit of poetry long continued to breathe in the forms of philosophy. Even Anaximander, and his immediate followers in the Ionic school, while writing in prose, appear, from a few fragments left to us, to have had much recourse to poetical expression, and often convey a dogma by an image; while, in the Eleatic school, Xenophanes and Parmenides adopted the form itself of verse, as the medium for communicating their theories; and Zeno, perhaps from the new example of the drama, first introduced into philosophical dispute that fashion of dialogue which afterward gave to the sternest and loftiest thought the animation and life of dramatic pictures. XVI. But even before the Eleatic school arose, the most remarkable and ambitious of all the earlier reasoners, the arch uniter of actual politics with enthusiastic reveries--the hero of a thousand legends--a demigod in his ends and an impostor in his means--Pythagoras of Samos --conceived and partially executed the vast design of establishing a speculative wisdom and an occult religion as the keystone of political institutions.