Much will be uprooted, and it is possible that even the defiant "ignorabimus," the antipole of the search for truth from Pyrrhon to Dubois, will again take up the cudgel. For in the face of despairing uncertainty there is the one certainty: what cannot be comprehended is being encircled more and more by the great discoverers! And even if the absolute point of convergence can never be reached, there is within our reach at least another point which is a haven of rest in the passing stream of philosophies, namely, a moral centre around which eddies of happiness circle. At the heart of this world-view there is the uplifting belief in an advance of knowledge in spite of all, and a belief in the vanishing of age-long problems and difficulties under the flood of discoveries. And even if afterwards and concurrently ever new problems and difficulties arise, these do not suppress our feeling of triumph. Every achievement in this field gives us a sense of enfranchisement from prejudices, not the least of which is narrowness of national outlook. Not only do discoverers construct bridges of thought that stretch to astronomical distances, but, what is more difficult, they build bridges for our feelings, that surmount political obstacles. Every thinking being who plays a part in the making of some great discovery and who, with deepened vision, bows before a new achievement of mind, gradually becomes a disciple of the religion of universal politics, the creed of which is faith in the brotherhood of thought. The nucleus of a philosophy that belongs to the future is the recognition that differing national view must be compounded into a unity, and that every great discovery means a step towards attaining this end. Even if we accept Pascal's wonderful dictum that human knowledge is represented by a sphere which is continually growing and increasing its points of contact with the unknown, we must not interpret it as a sign of despair. It is not the enlargement of the unknown, but only that of knowledge that stirs our feelings with ethical forces. The positive calls up in us a living force by inspiring in us the feeling that the sphere of knowledge is destined to grow, and that there can be no higher duty for all the energies of mind than to obey the call for combined action towards this growth which will bring the world into harmony. Full of such reflections I entered the home of the great discoverer, whose activities unceasingly hovered before my vision as ideal examples of creative effort. I discovered him, as almost always, seated before loose sheets of paper which his hand had covered with mathematical symbols, with hieroglyphics of that universal language in which, according to Galilei, the great book of Nature is written.