Consequently the discussion of the question whether America is superior to Europe or Europe to America is a futile enterprise and labour lost; because the balance between the differences is rapidly adjusting itself. Nevertheless, if any difference exists to-day between the two continents, it is undoubtedly this: that all the phenomena of social life in America are simpler and clearer, and less overlaid and obscured by traditions, institutions, and century-old ideas and sentiments than in Europe. For this reason, the careful observer will find in America a much more profitable field for the study of the dangerous tendencies and exaggerations of modern civilisation which are common to Europe and America. Of these dangerous tendencies, the one which has struck me most in the course of my travels in America, and has given me most food for thought, is precisely this, which I have treated in this my latest work and which forms, as it were, the crown to the whole discussion of the dialogue. Modern civilisation has accomplished miracles and marvels without number, since she left behind her the limits, material and ideal, within which the timid generations of old confined themselves,—since she outstepped and upset these limits on her way to conquer the earth, riches, and liberty. Now, however, precisely because she has crossed all the limits and no longer has any before her, she finds herself impelled on every side, in politics, customs, morals, art, and philosophy, to excesses which may one day prove very dangerous. Men are beginning to have a vague presentiment of this danger. They do not clearly see, however, the quarter from which it threatens. They disquiet themselves without thoroughly diagnosing the evil. And this disquietude may perhaps explain the pessimism which afflicts a civilisation so flourishing and fortunate in many respects as that of our own times.