This is only an analogy, and analogies are dangerous if used as arguments. But it may contain a helpful suggestion. Transferred to the field of population, it means that true and complete assimilation of the foreign elements in the United States involves such a complete transformation and unification of the new constituents that all sense of difference between the new and the old completely disappears. The idea of a type, into conformity with which the new elements must be brought, is here present also. In the case in point, this is manifestly the “American type.” Just what this is, it might be difficult to say. Some writers appear even to question its existence. But the very idea of assimilation presupposes a type. In general terms, this type in the United States is the “native American.”[357] A foreigner, or the descendant of a foreigner, can be truly said to be assimilated only when the natives around him are conscious of no feeling of alienation on account of his origin, and when the newcomer himself feels no degree of separateness, nor possesses divergent interests or loyalties traceable to the source from which he came. This is not inconsistent with the fact that certain elements contribute more fully to specific characteristics of the body politic than others. The political, religious, or artistic aspects of the national life may, in fact, owe their character more to one element of the population than to another. But if assimilation is complete, there can be no disturbances or friction arising from differences of origin among the members of the nation. Perhaps the most efficient test of entire assimilation is that of free intermarriage. If marriage might take place between any man and woman in the country, without suggesting differences of race or ethnic origin to either contracting party, or their families, it is a safe evidence of complete assimilation. There may be objections on the grounds of wealth, social station, or religion; there must be none based on race. This may seem like strong doctrine. It may, indeed, not be necessary for the welfare of the country that assimilation should be so thoroughgoing as this. It is possible that different racial groups within the body politic do not constitute a menace. But if so, the fact should be stated by saying that complete assimilation is not necessary, rather than by saying that the absence of serious difficulties or evils arising from a composite population is a proof of complete assimilation. It is disheartening to note the frequency with which even careful writers on the subject accept trivial and superficial indications as evidence of the assimilation of our foreign residents. The wearing of American clothes, the laying of carpets on the floors, the abandonment of sleeping in the kitchen and taking large numbers of boarders, the use of better food, and most of all the knowledge of English are taken as proofs of assimilation.