From the point of view of the humanist, what has so suddenly collapsed is the towering structure of nineteenth-century romanticism, not any dwelling necessary to the continued life of poetry. For he has long recognised those metaphysical limitations with which contemporary physics is so deeply entangled; and he has been unwilling to trust metaphysics, any more completely than natural science, with the whole determination of a philosophy of life. Instead of asserting that intellectual certainty in the field of science is available now almost for the first time on an unlimited scale, he would postulate a large degree of what amounts to _practical_ certainty, in all that concerns us most nearly as ethical beings, available now, as it has been for centuries. This assurance is embodied, for him, in the dualism of the great historic religions, in the teachings of Socrates and of Jesus, and in the most persistent traditions of European literature. But its final sanctions are not found in any “great tradition,” however imposing; they are arrived at empirically and experimentally by any one who, divesting his mind of shibboleths and catch-words, will honestly examine his own impulses and springs of action. In his own soul he will find the cleavage, the dualism, which runs through human nature. This opposition of forces, by whatever names he calls them, by whatever symbols he represents them, may never be resolved; but in his mysterious power of intervention in their unending conflict lies, for him, the ultimate reality within the illusion. To the reading of poetry, then, he will bring the same habit of discrimination that serves him in the conduct of life, mindful that it is still a world communicating with ours by the gate of horn and the gate of ivory, and that the phantasms which issue therefrom may light our way a few steps nearer truth, or may deepen for us the shadows of the dark, chaotic flux.