One cannot pass twice through the same stream.( . Plato’s Cratyllus, § 402.) Heraclitus the obscure had a disciple who did not stop with that, he went further and added, “One cannot do it even once."( Cf. Tenneman, Geschichte der Philosphie, I, p. 220,) Poor Heraclitus, to have such a disciple! By this amendment the thesis of Heraclitus was so improved that it became an Eleatic thesis which denies movement, and yet that disciple desired only to be a disciple of Heraclitus. . .and to go further — not back to the position Heraclitus had abandoned.