=317. Increase in the relative importance of commerce.=—Not less striking than this growth in absolute quantity, as measured in current values, is the growth compared with the estimated increase of the world’s population. The value _per capita_ (“by head”) of a country’s commerce is secured by dividing the total amount of trade by the number of inhabitants; it shows the average share of each person in commerce, and furnishes, therefore, some index of the relative importance of commerce in different times and places. Now, even if this value _per capita_ had remained the same we should regard the absolute increase in commerce as a very important fact. Commerce, however, has actually increased much faster than population; the share of the average human being in the world’s trade has grown over tenfold. Let the student reflect on the difference it would make to him whether he had $2 or $20 for spending money in a given time, and consider the extra articles he could buy with the larger sum; he will then be better able to appreciate the broadening and deepening of the commercial current in recent times. =318. The world now passing through a commercial revolution.=—The student is now in a position to understand the significance of the statement of an English writer, that “the commerce of the world may almost be said to be the creation of the past seventy-five years.” We are living in the midst of a vast, though silent, revolution. Reference to the figures will show that the process of change quickened strikingly in the latter half of the century, and at its close we still do not dare to say when the movement will slacken. The change which we find so marked in commerce affects equally other sides of human life. An American author, Adams, writing in 1871, could say with truth that “the discoveries of Guttenberg and Columbus have produced more startling and more clearly defined results upon the destinies of the human race within the last twenty-five years than in any other equal period of time during the four previous centuries.” Have the results been less startling in the quarter-century that followed? Another American economist, Wells, said about 1890, “When the historian of the future writes the history of the nineteenth century he will doubtless assign to the period embraced by the life of the generation terminating in 1885 a place of importance, considered in its relations to the interests of humanity, second to but very few, and perhaps to none, of the many similar epochs in time in any of the centuries that have preceded it.” Is the generation terminated in 1915 willing to admit that it takes a less important place in history than its predecessor?