Heracliteanism had grown to be almost identical with the famous doctrine of the sophist Protagoras, that the momentary, sensible apprehension of the individual was the only standard of what is or is [132] not, and each one the measure of all things to himself.

The impressive name of Heraclitus had become but an authority for a philosophy of the despair of knowledge.
And as it had been with his original followers in Greece, so it happened now with the later Roman disciple.

He, too, paused at the apprehension of that constant motion of things--the drift of flowers, of little or great souls, of ambitious systems, in the stream around him, the first source, the ultimate issue, of which, in regions out of sight, must count with him as but a dim problem.

The bold mental flight of the old Greek master from the fleeting, competing objects of experience to that one universal life, in which the whole sphere of physical change might be reckoned as but a single pulsation, remained by him as hypothesis only--the hypothesis he actually preferred, as in itself most credible, however scantily realisable even by the imagination--yet still as but one unverified hypothesis, among many others, concerning the first principle of things.

He might reserve it as a fine, high, visionary consideration, very remote upon the intellectual ladder, just at the point, indeed, where that ladder seemed to pass into the clouds, but for which there was certainly no time left just now by his eager interest in the real objects so close to him, on the lowlier earthy steps nearest the ground.