Friedrich Nietzsche was an optimist. It was a paradox of courage. There is nothing nobler or more valiant in the history of thought than his refusal to let the sun be dimmed by the mist of his own suffering. "No invalid has the right to be a pessimist." "Let them beware: the years in which my vitality sank to its minimum were those in which I ceased to be a pessimist." That is magnificent, but it is not philosophy. If Nietzsche by his insomnia and his wounded eyes is pledged on the point of honour to optimism, is not Schopenhauer by his fixed income and excellent digestion similarly pledged to pessimism? But Zarathustra's optimism is not merely positive, it is ecstatic: to express its fulness he creates the formula of the Eternal Return. He claps his hands and cries "Encore!" to life. He is drunken with joy as men are in the taverns with corn and the grape, and he shouts "The same again!" This Eternal Return is presented to us as a conclusion of mathematical physics and spectrum analysis. St. Thomas Aquinas taught, following Aristotle, that the stars were composed of a substance nobler than that of earth, not subject to birth or death, and so immune from corruption. But Fraunhofer and his successors have, with their prisms and telescopes, discovered in the stars the same eighty-one or eighty-two elements which constitute the earth. Since then we have but a finite number of indestructible elements and forces, and an infinite space and time--or at least a space and time to which we can conceive no limits--it must follow that the same combinations will repeat themselves incessantly both in space and time. There is not only an Eternal Return, but an Infinite Reduplication. And if thought, as Nietzsche assumed, is only the phosphorescence accompanying certain arrangements of matter, the same conscious life must also repeat itself. One does not stay to discuss this phantasy of mathematics except to say that whoever was entitled to entertain it Zarathustra was not. If science is, as he held, a mere linked illusionism, how can it give so absolute a prophecy? To Nietzsche it was no conclusion, but a reminiscence from Greek speculation which came to him, disguised in the flame of an inspiration, under that pyramidal rock near Sorlei, "six thousand feet above men and time." He accepted it because it seemed to him the supreme formula of optimism. His mind was incited to it perhaps by that sombre passage in which his rejected master, Schopenhauer, declares that if you were to knock on the graves, with power to summon forth the dead to rise up and live their lives again, none would answer to your call. Christianity agrees with Schopenhauer; for though Christianity is an optimism, it is founded on pessimism. It is an optimism poised on a centre that does not lie within the walls of space and time. Christianity called a new world into existence to redress the balance of the old; and were this old world all--a closed