Thus, as we have already seen, there may be a special particle applying to blood-relations as non-transferable possessions.
Or, again, one Australian language has special duals, "we-two," one to be used between relations generally, another between father and child only.

Or an American language supplies one kind of plural suffix for blood-relations, another for the rest of human beings.

These linguistic concretions are enough to show how hard it is for primitive thought to disjoin what is joined fast in the world of everyday experience.
No wonder that it is usually found impracticable by the European traveller who lacks an anthropological training to extract from natives any coherent account of their system of relationships; for his questions are apt to take the form of "Can a man marry his deceased wife's sister ?" or what not.

Such generalities do not enter at all into the highly concrete scheme of viewing the customs of his tribe imposed on the savage alike by his manner of life and by the very forms of his speech.

The so-called "genealogical method" initiated by Dr.
Rivers, which the scientific explorer now invariably employs, rests mainly on the use of a concrete type of procedure corresponding to the mental habits of the simple folk under investigation.