Here are differences in the character of the cultural life which can scarcely be measured quantitatively in terms of gross intellectual capacity. Historical causes do not, it seems, adequately account for them. So far as this is true we are perhaps warranted in regarding them as modifications of transmitted tradition due to innate traits of the people who have produced them. Granted that civilization, as we find it, is due to the development of communication and the possibility of mutual exchange of cultural materials, still every special culture is the result of a selection and every people borrows from the whole fund of cultural materials not merely that which it can use but which, because of certain organic characteristics, it finds stimulating and interesting. The question then resolves itself into this: How far do racial characteristics and innate biological interests determine the extent to which one racial group can and will take over and assimilate the characteristic features of an alien civilization? How far will it merely take over the cultural forms, giving them a different content or a different inflection? This problem, so far as it is related to the lives of primitive peoples, has already been studied by the ethnologists. Rivers, in his analysis of the cultures of Australian people, has found that what we have hitherto regarded as primitive cultures are really fusions of other and earlier forms of culture.[3] The evidence of this is the fact that the fusion has not been complete. In the process of interchange it frequently happens that what Rivers calls the "fundamental structure" of a primitive society has remained unchanged while the relatively formal and external elements of alien culture only have been taken over and incorporated with it. There are indications also that, where cultural borrowings have taken place, the borrowed elements have for the people who have taken them over a meaning different from what they had for the people from whom they were borrowed. W.J. McGee, in an article entitled "Piratical Acculturation," has given an interesting illustration of this fact.[4] McGee's observations of the Beri Indians go to show that they imitated the weapons of their enemies, but that they regarded them as magical instruments and the common people did not even know their names. There are numerous other illustrations of this so-called "piratical acculturation" among the observations of ethnologists. It is said that the Negroes in Africa, when they first came into possession of the white man's guns, regarded them as magical instruments for making a noise and used them, as the Germans used the Zeppelins and the newspapers, merely to destroy the enemy's morale.