For Parmenides, at his early day, himself, as some remnants of his work in that direction bear witness, an acute and curious observer of the concrete and sensible phenomena of nature, that principle of reasonable unity seemed attainable only by a virtual negation, by the obliteration, of all such phenomena. When we have learned as exactly as we can all the curious processes at work in our own bodies or souls, in the stars, in or under the earth, their very definiteness, their limitation, will but make them the more antagonistic to that which alone really is, because it is always and everywhere itself, identical exclusively with itself. Phenomena!--by the force of such arguments as Zeno's, the instructed would make a clean sweep of them, for the establishment, in the resultant void, of the "One," with which it is impossible (para panta legomena)+ in spite of common language, and of what seems common sense, for the "Many"--the hills and cities of Greece, you and me, Parmenides himself, really to co-exist at all. "Parmenides," says one, "had stumbled upon [38] the modern thesis that thought and being are the same." Something like this--this impossibly abstract doctrine--is what Plato's "father in philosophy" had had to proclaim, in the midst of the busy, brilliant, already complicated life of the recently founded colonial town of Elea. It was like the revelation to Israel in the midst of picturesque idolatries, "The Lord thy God is one Lord";+ only that here it made no claim to touch the affections, or even to warm the imagination. Israel's Greek cousin was to undergo a harder, a more distant and repressive discipline in those matters, to which a peculiarly austere moral beauty, at once self-reliant and submissive, the aesthetic expression of which has a peculiar, an irresistible charm, would in due time correspond. It was in difficult hexameter verse, in a poem which from himself or from others had received the title--Peri physeôs+ (De Naturâ Rerum) that Parmenides set forth his ideas. From the writings of Clement of Alexandria, and other later writers large in quotation, diligent modern scholarship has collected fragments of it, which afford sufficient independent evidence of his manner of thought, and supplement conveniently Plato's, of course highly subjective, presentment in his Parmenides of what had so deeply influenced him.-- [39] "Now come!" (this fragment of Parmenides is in Proclus, who happened to quote it in commenting on the Timaeus of Plato) "Come! do you listen, and take home what I shall tell you: what are the two paths of search after right understanding. The one, hê men hopôs estin te kai hôs ouk esti mê einai?+ "that what is, is; and that what is not, is not"; or, in the Latin of scholasticism, here inaugurated by Parmenides, esse ens: non esse non ens-- peithous esti keleuthos; alêtheiê gar opêdei?+