We returned to Italy in November. I recrossed the ocean from Rio de Janeiro to Genoa in fifteen days, during which I reread my books of philosophy. But the pages of Bergson, Kant, and Comte, which I read in mid-ocean, no longer riveted my attention as they had on the way out. For in the time for thought afforded me by the crossing, far from the world and its troubles, I plunged day by day in a more intense meditation on American progress, which, of all the things and phenomena I had witnessed, was that which had left on me the liveliest impressions. It was clear that it was not a theoretical idea, but a passion, a faith, a religion fervently embraced by nearly everybody. All the arguments which I had advanced to subject it to criticism had been fruitless; and not only ignorant men, and those eager to make money, but the most highly cultivated minds, the very intellectual élite of America, were blind to the contradictions and logical shortcomings of this conception. Nevertheless, was not this but an additional reason for studying this phenomenon thoroughly? It is not ideas which move and transform the world, but passions; and a passion, even if it be absurd, is a thousand times more powerful than a wise idea. Now it was not difficult to see what would happen if this religion of American progress spread through the world. Europe would lose, so to speak, her rights of historical primogeniture, and all her ancient civilisation would lose a great part of its value. If the rapid increase of riches is the supreme measure of civilisation, and if, in consequence, the efforts of a people must be concentrated on everything which can accelerate this increase, it is clear that the most ancient, populous, and glorious countries of Europe will not be able to keep pace with the young countries and with the nations which are masters of vast territories; and that, bit by bit, the most glorious civilisations of Europe will come to be regarded by the eyes of the rising generations as relics and fossils of another age. This danger no longer appeared to me so distant and hypothetical as to many other Europeans. After what I had seen in America, many facts and thoughts and tendencies to which I had hitherto paid scarcely any attention in Europe, seemed to me to acquire a new significance. I saw everywhere, even in the ancient world, traces and proofs of the rapid spread of the American idea of progress, especially among the nations like Germany, which have developed industry to a great, perhaps a too great, extent; and in all the countries, classes, and professions which have identified their interests most completely with those of industry. So the enemy who threatened the destruction of the ancient civilisation of Europe had already invaded the Old World.