The human groups thus called upon to surrender their contributions to the history of man are of various formations, and consist of various kinds of social units. There is no one term which can properly be applied to all, and it will have been noted that I have carefully avoided giving the human groups hitherto dealt with any particular name, and only under protest have I admitted the terms used by the authorities I have quoted. I think the term "tribe" is not applicable to savage society, for it is used to denote peoples in all degrees of social evolution, and merely stands for the group which is known by a given name, or roams over a given district. But the use of this term is not so productive of harm as the use of the term "family," because of the universal application of this term to the smallest social unit of the civilised world, and because of the fundamental difference of structure of the units which roughly answer to the definition of family in various parts of the world. It is no use in scientific matters to use terms of inexact reference. As much as almost anything else it has led to false conclusions as to the evolution of the family, conclusions which seem to entangle even the best authorities in a mass of contradictions. I cannot think of a family group in savagery with father, mother, sons, and daughters, all delightfully known to each other, in terms which also belong to the civilised family, and still less can I think of these terms being used to take in the extended grouping of local kinships. One of our greatest difficulties, indeed, is the indiscriminate use of kinship terms by our descriptive authorities. We are never quite sure whether the physical relationships included in them convey anything whatever to the savage. If he knows of the physical fact, he does not use it politically, for blood kinship as a political force is late, not early, and the early tie was dependent upon quite other circumstances. Over and over again it will be found stated by established authorities that the family was the primal unit, the grouped families forming the larger clan, the grouped clans forming the larger tribe. This is Sir Henry Maine's famous formula, and it is the basis of his investigation into early law and custom.[326] It is founded upon the false conception of the family in early history, and upon a too narrow interpretation of the stages of evolution. When we are dealing with savage society, the terms family and tribe do not connote the same institution as when we are dealing with higher forms of civilisation. There is something roughly corresponding to these groupings in both systems, but they do not actually equate. When we pass to the Semitic and the Aryan-speaking peoples, both the family and tribe have assumed a definite place in the polity of the races which is not to be found outside these peoples.