The question now is: What is the real distinction between these nations? Is it the physical differences of blood, color and cranial measurements? Certainly we must all acknowledge that physical differences play a great part, and that, with wide exceptions and qualifications, these eight great races of to-day follow the cleavage of physical race distinctions; the English and Teuton represent the white variety of mankind; the Mongolian, the yellow; the Negroes, the black. Between these are many crosses and mixtures, where Mongolian and Teuton have blended into the Slav, and other mixtures have produced the Romance nations and the Semites. But while race differences have followed mainly physical race lines, yet no mere physical distinctions would really define or explain the deeper differencesthe cohesiveness and continuity of these groups. The deeper differences are spiritual, psychical, differences undoubtedly based on the physical, but infinitely transcending them. The forces that bind together the Teuton nations are, then, first, their race identity and common blood; secondly, and more important, a common history, common laws and religion, similar habits of thought and a conscious striving together for certain ideals of life. The whole process which has brought about these race differentiations has been a growth, and the great characteristic of this growth has been the differentiation of spiritual and mental differences between great races of mankind and the integration of physical differences.
The age of nomadic tribes of closely related individuals represents the maximum of physical differences. They were practically vast families, and there were as many groups as families. As the families came together to form cities the physical differences lessened, purity of blood was replaced by the requirement of domicile, and all who lived within the city bounds became gradually to be regarded as members of the group; i.e., there was a slight and slow breaking down of physical barriers. This, however, was accompanied by an increase of the spiritual and social differences between cities. This city became husbandmen, this, merchants, another warriors, and so on. The ideals of life for which the different cities struggled were different. When at last cities began to coalesce into nations there was another breaking down of barriers which separated groups of