"When we think of the future and of the coming generations, the millions of human beings who will differ from us in habits and customs, and we try in imagination to fancy them with us, we wonder from where they will spring, where they are now? Where is this fecund chaos, rich in worlds, that hides the generations that are to be? And where can it be save there, where every reality has been and will be,--here, in the present, and what it contains. And you, foolish questioner, who do not recognize your own essence, you are like the leaf on the tree which, withering in autumn, and feeling it is about to fall, laments at death, inconsolable at the knowledge of the fresh verdure which in spring will cover the tree once more. The leaf cries, 'I am no more.' Foolish leaf, where do you go? Whence do the fresh leaves come? Where is this chaos whose gulf you fear? See, your own self is in that force, interior and hidden, acting on the tree which, through all generations of leaves, knows neither birth nor death. And now tell me," Schopenhauer concludes, as though he were about to pronounce a benediction, "tell me, is man unlike the leaf?" This doctrine, which teaches that through all there is one invariable, identical, and equal force, is the great problem whose solution was sought by Kant, and which he gave up in despair; it is the discovery which makes of Schopenhauer one of the foremost thinkers of the century, and one, it may be added without any unguarded enthusiasm, which will suffice to carry his name into other ages, somewhat in the same manner as the name of Columbus has descended to us. "If we were to consider," he said, "the nature of this force which admittedly moves the world, but whose psychological examination is so little advanced that the most certain analytical results seem not unlike a paradox, we should be astonished at this fundamental verity which I have been the first to bring to light, and to which I have given its true name,--Will. For what is the world but an enormous Will constantly irrupting into life. Gravitation, electricity, heat, every form of activity, from the fall of an apple to the foundation of a republic, is but the expression of Will, and nothing more."