Only by such a description can we reach a correct and scientific definition of a given institution in a given society. It is essential that the elements of this definition should be taken from the conditions of social life in the given society. As an example we may take the legal side of marriage. Amongst us marriage is a legal act enforced on the one hand by the authority of the law with all its complicated social working and the power of the State at its back; on the other hand by the authority of the Church, which exercises a profound moral pressure in relation to this institution. These or even analogous factors will be sought in the Australian tribes in vain. And yet marriage there is not deprived of its legal validity and of its social sanction. It is not an act of mere fancy, brutal force or accident, but the legal factors have there quite a specific character, and can be found and understood only in connection with the general tribal structure and government. Besides all that has been said above against a general offhand affirmation, that the individual family exists in Australia, it may be added here that such an assertion is practically quite useless. No further conclusions or inferences can be drawn from such a vague statement. Only by knowing exactly and minutely all the features and characters of the said unit can the different questions attached to this problem be answered; only so can it be judged whether the individual family or certain features of it are survivals or innovations; or whether they are so deeply rooted and connected with the social life and the whole organization of the tribes, that neither of these suppositions is justifiable. Such special and concrete definitions of a given social phenomenon in a given ethnic area, as the one which it is intended to give here for the Australian individual family, can serve also as a basis to form by induction a general conception of the individual family; and only from a rich collection of such material from different peoples can any sociological laws be constructed. As said above, a general working definition of the word individual family may be accepted at the outset of our investigations. After a careful analysis of all particular relationships concerned; and further, of the economic unity of the family, division of labour within it, legal sanction, etc., content can be given to the rough definition laid down at the beginning, and scientific exactness can be given to our conception of the individual family in Australia.