[354] "In the study of population ... the facts of aggregation or grouping are the first to claim our attention." (F. H. Giddings, _Princ. of Sociology_, p. 79). In fact all the social phenomena of higher order corresponding to differentiation and constitution depend upon the facts of grouping. In the lowest societies, as the Australian, the mode of living in very small groups precludes _a priori_ the possibility of any higher social formations. We may say that the social horizon of a community extends as far as the contact of its members. In higher societies this contact need not necessarily be an actual one; as a rule in more developed communities members of a social unit (nation, town, association) only come exceptionally and in a diminutive degree into immediate contact. But there are innumerable ways of mental contact. On the contrary there is no other form of contact but the personal one among the Australian blacks, and it is the first condition for the formation of any social bonds amongst them. In the discussion of all kinship bonds we should never lose sight of the fact that it is highly improbable that people who never were in personal contact could feel more closely related than people who usually live together. [355] The importance of the aboriginal mode of living in the study of family life and kinship bonds has been well brought out by Dr. Westermarck (_H.H.M._, pp. 42 _sqq._, especially pp. 43-47). His general inference--that in low societies the scattered mode of living brings into prominence individual kinship bonds, and isolates the family unit--will be corroborated by our conclusions drawn from the Australian material. The few Australian examples--quoted and interpreted by Dr. Westermarck--have been vehemently disputed by Herr Cunow (_loc. cit._, p. 122, footnote). His criticism, if compared with the data presented in this chapter, will appear quite unfounded. Herr Cunow's book does not, by the way, deserve its good reputation. There are many statements in it, given without references, which I have been unable to verify in the first hand evidence.