matical and scientific books, which he specifies.[1] We know also that a year after he had made his first fragmentary formulation of it, he wished to test and criticise it afresh, and proposed an extended course of study at Vienna (or Paris or Munich)—he would stop writing for several years, he declared, and begin student-life over again. Unhappily (or happily) the plan could not be carried out, because of poor health, and particularly the state of his eyes. k And yet it must be doubted whether scientific and physical studies such as he looked forward to, however careful and extended they might be, could ever dispose of questions of this far-reaching nature. Professor Fouillée called speculations like Nietzsche's "toutes subjectives."[2] The element of truth in the reproach is that in the nature of the case they are incapable of scientific verification. How can one by experimental investigation decide whether the sum-total of force in the universe is finite or infinite? How can there be a scientific demonstration of the state of the cosmos billions of years ago, or billions of years to come? How can one get objective evidence that time is unending or that empty space is unreal! How at the very best can we get beyond certain necessities of thought, which it is open to any one to pronounce "toutes subjectives"? The fact is that probabilities or possibilities are all we can have in regions like these—and yet must we not proceed on probabilities and possibilities in our concrete (as opposed to formal) thinking almost everywhere! However this may be, Nietzsche never had his years of projected study, and never got beyond such fragmentary formulations of his doctrine as we have, and the lyrical expression of it in Zarathustra.
IV
Nietzsche is commonly taxed with error in claiming to be the first to teach the doctrine. Indeed he himself says that it might have been taught by Heraclitus—that at least the Stoa, which inherited nearly all its fundamental conceptions from
