It is necessary, therefore, in planning our movements, in guiding our future development, that at times we rise above the pressing, but smaller questions of separate schools and cars, wage-discrimination and lynch law, to survey the whole question of race in human philosophy and to lay, on a basis of broad knowledge and careful insight, those large lines of policy and higher ideals which may form our guiding lines and boundaries in the practical difficulties of every day. For it is certain that all human striving must recognize the hard limits of natural law, and that any striving, no matter how intense and earnest, which is against the constitution of the world, is vain. The question, then, which we must seriously consider is this: What is the real meaning of Race; what has, in the past, been the law of race development, and what lessons has the past history of race development to teach the rising Negro people? When we thus come to inquire into the essential difference of races we find it hard to come at once to any definite conclusion. Many criteria of race differences have in the past been proposed, as color, hair, cranial measurements and language. And manifestly, in each of these respects, human beings differ widely. They vary in color, for instance, from the marble-like pallor of the Scandinavian to the rich, dark brown of the Zulu, passing by the creamy Slav, the yellow Chinese, the light brown Sicilian and the brown Egyptian. Men vary, too, in the texture of hair from the obstinately straight hair of the Chinese to the obstinately tufted and frizzled hair of the Bushman. In measurement of heads, again, men vary; from the broad-headed Tartar to the medium-headed European and the narrow-headed Hottentot; or, again in language, from the highly-inflected Roman tongue to the monosyllabic Chinese. All these physical characteristics are patent enough, and if they agreed with each other it would be very easy to classify mankind. Unfortunately for scientists, however, these criteria of race are most exasperatingly intermingled. Color does not agree with texture of hair, for many of the dark races have straight hair; nor does color agree with the breadth of the head, for the yellow Tartar has a broader head than the German; nor, again, has the science of language as yet succeeded in clearing up the relative authority of these various and contradictory criteria. The final word of science, so far, is that we have at least two, perhaps three, great families of human beings--the whites and Negroes, possibly the yellow race. That other races have arisen from the intermingling of the blood of these two. This broad division of the world's races which men like Huxley and Raetzel have introduced as more nearly true than the old five-race scheme of Blumenbach, is nothing more than an acknowledgment that, so far as purely physical characteristics are concerned, the differences between men do not explain all the differences of their history.