So two persons who, starting from these two definitions of progress, set to work to judge the past and the present, Europe and America, will never succeed in understanding each other, any more than two persons who, wishing to measure a thing together, adopt two different measures. And the discussion will be the more vain and confused, the less clearly and precisely the thought of each disputant apprehends the primary definition of progress, which does duty as a measure for each. Indeed, this unfortunate state of affairs is commoner than is generally supposed at the present day, with the need for hurry which pursues us in every act and at every moment, and with the great whirl of ideas and words which eddies around us. To decide, then, whether our times are or are not greater than those of the ancients, whether America is superior to Europe or Europe to America, we must discover which of these two definitions is the true one. But is it possible to prove that one of these definitions of progress is true and the other false? How many to-day would dare to deny that man made the world progress when, by the use of fire, he launched on the path of victory the locomotive across the earth and the steamer across the ocean? Or when he captured and led through threads of copper the invisible force of electricity adrift in the universe? Or when he embellished the world with arts, and enlightened it with studies, and tempered the innate ferocity of human nature with laws, religion, and customs? It is clear that neither of these two definitions will succeed in putting the other out of court, until men are willing either to superhumanise themselves completely, renouncing material goods in favour of spiritual joys, or, sacrificing the latter to the former, to bestialise themselves. So long as men with few exceptions continue to desire riches and the control of nature, as well as beauty, wisdom, and justice, both these definitions of progress will be _partially_ true. Each will present to us one aspect of progress. It will be impossible, if we adopt only one of the two, to decide whether we are progressive or decadent, whether America is worth more or less than Europe. Every epoch and people will seem at one time and another to be progressive or decadent, to be superior or inferior, according as the one or the other definition is the basis of judgment. “But,” the reader will say, “why not then combine the two definitions in one? Why not say that progress is the increase of all the good things which man desires: of riches, of wisdom, of power, of beauty, of justice?” But in order to make of these two definitions a single complete and coherent definition, we should have to be certain that it is possible by a single effort to increase all the good things of life. Is it possible, and to what extent is it possible? That is a second grave question which this book and its successor endeavour to answer.