But what will be the effect of eternal recurrence upon the superman? The tragedy of it, as we have seen, will merely serve to make him heroic. He will defy the universe and say "yes" to life. Putting aside all thought of conscious existence beyond the grave, he will seek to live as nearly as possible in exact accordance with those laws laid down for the evolution of sentient beings on earth when the cosmos was first set spinning. But how will he know when he has attained this end? How will he avoid going mad with doubts about his own knowledge? Nietzsche gave much thought, first and last, to this epistemological problem, and at different times he leaned toward different schools, but his writing, taken as a whole, indicates that the fruit of his meditations was a thorough-going empiricism. The superman, indeed, is an empiricist who differs from Bacon only in the infinitely greater range of his observation and experiment. He learns by bitter experience and he generalizes from this knowledge. An utter and unquestioning materialist, he knows nothing of mind except as a function of body. To him speculation seems vain and foolish: his concern is ever with imminent affairs. That is to say, he believes a thing to be true when his eyes, his ears, his nose and his hands tell him it is true. And in this he will be at one with all those men who are admittedly above the mass today. Reject empiricism and you reject at one stroke, the whole sum of human knowledge.
When a man stubs his toe, for example, the facts that the injured member swells and that it hurts most frightfully appear to him as absolute certainties. If we deny that he actually knows these things and maintain that the spectacle of the swelling and the sensation of pain are mere creatures of his mind, we cast adrift from all order and common-sense in the universe and go sailing upon a stormy sea of crazy metaphysics and senseless contradictions. There are many things that we do not know, and in the nature of things, never can know. We do not know why phosphorus has a tendency to combine with oxygen, but the fact that it has we do know--and if we try to deny we do know it, we must deny that we are sentient beings, and in consequence, must regard life and the universe as mere illusions. No man with a sound mind makes any such denial. The things about us are real, just as our feeling that we are alive is real.[4]
From this it must be plain that the superman will have the same guides that we have, viz.: his instincts and senses. But in him they will be more accurate and more acute than in us, because the whole tendency of his scheme of things will be to fortify and develop them.[5] If any race of Europe devoted a century to exercising its right arms, its descendants, in the century following, would have right arms like piston-rods. In the same way, the superman, by subordinating everything else to his instinct to live, will make it evolve into something very accurate and efficient. His whole concern, in brief, will be to live as long as possible and so to avoid as much as possible all of those things which shorten life--by injuring the body from without or by using up energy within. As a result he will cease all effort to learn why the world exists and will devote himself to acquiring knowledge how it exists. This knowledge how will be within his capacity even more than it is within our capacity today. Our senses, as we have seen, have given us absolute knowledge that stubbing the toe results in swelling and pain. The superman's developed senses will give him absolute knowledge about everything that exists on earth. He will know exactly how a tubercle bacillus attacks the lung tissue, he will know exactly how the blood fights the bacillus, and he will know exactly how to interfere in this battle in such a manner that the blood shall be invariably victorious. In a word, he will be the possessor of exact and complete knowledge regarding the working of all the benign and malignant forces in the world about him, but he will not bother himself about insoluble problems. He will waste no time speculating as to why tubercle bacilli were sent into the world: his instinct to live will be satisfied by his success in stamping them out.
The ideal superman then is merely a man in whom instinct works without interference--a man who feels that it is right to live and that the only knowledge worth while is that which makes life longer and more bearable. The superman's instinct for life is so strong that its mere exercise satisfies him, and so makes him happy. He doesn't bother about the unknown void beyond the grave: it is sufficient for him to know that he is alive and that being alive is pleasant. He is, in the highest sense, a utilitarian, and he believes to the letter in Auguste Comte's[6] dictum that the only thing living beings can ever hope to accomplish on earth is to adapt themselves perfectly to the natural forces around them--to the winds and the rain, the hills and the sea, the thunderbolt and the germ of disease.