But if the reasons are hard to trace, the fact is no longer open to intelligible doubt. Physiology tells us that it manifests itself at birth; history, that it has formed a channel for the whole course and current of events. There is no crisis so great, there is no occurrence so trivial, as not to exhibit in some degree its presence and efficacy in the life of man. Nations at peace do not follow the same policy; nations in conflict do not fight with the same weapons; the contrast of laws and customs is so vivid that it has led some impatient philosophers to consider all morality relative. And what is true of the life as a whole is equally true of its specialisation in art and literature. For these are pre-eminently the expression of the national voice, as intimate as its language, as vital as the breath that it draws, and every artist who has compelled the attention of the world at large has done so by addressing it as the spokesman of his own people. No doubt there are other factors in the case, the personal idiosyncrasy that separates a man from his fellows, and again the general principles, fewer perhaps than is commonly supposed, that underlie all sense of rhythm and all appreciation of style. But to say this is only to say that the artist is himself, and that he belongs to our common humanity. In everything, from the conception of a poem to the structure of a sentence, the national element bears its part with the other two; it colours the personal temperament, it gives a standpoint from which principles of style are approached, and wherever its influence is faint or inconsiderable the work of the artist will be found to suffer in proportion. It is hardly necessary to add that the law holds equally good whether the race in question be pure or mixed. If the former, it will move along a single line: if the latter, it will mark the converging point of many; but in either case its operation is a sure test of genuineness both in feeling and expression. Occasionally, it may be, a careless public has been deceived by some trick of imitation—by the Spanish comedies of Clara Gazul or the Persian Lyrics of Mirza Schaffy; but such instances of deception no more traverse the law than the Ireland forgeries or the pictures of Cariani. Some men are born with a talent of mimicry: none have ever by its means attained to greatness.