s of race, language, and
culture. The coincidences of cleavage point merely to a readily
intelligible historical association. If the Bantu and Bushmen are so
sharply differentiated in all respects, the reason is simply that the
former are relatively recent arrivals in southern Africa. The two
peoples developed in complete isolation from each other; their present
propinquity is too recent for the slow process of cultural and racial
assimilation to have set in very powerfully. As we go back in time, we
shall have to assume that relatively scanty populations occupied large
territories for untold generations and that contact with other masses of
population was not as insistent and prolonged as it later became. The
geographical and historical isolation that brought about race
differentiations was naturally favorable also to far-reaching variations
in language and culture. The very fact that races and cultures which are
brought into historical contact tend to assimilate in the long run,
while neighboring languages assimilate each other only casually and in
superficial respects[191], indicates that there is no profound causal
relation between the development of language and the specific
development of race and of culture.

[Footnote 189: The Fijians, for instance, while of Papuan (negroid)
race, are Polynesian rather than Melanesian in their cultural and
linguistic affinities.]

[Footnote 190: Though even here there is some significant overlapping.
The southernmost Eskimo of Alaska were assimilated in culture to their
Tlingit neighbors. In northeastern Siberia, too, there is no sharp
cultural line between the Eskimo and the Chukchi.]

[Footnote 191: The supersession of one language by another is of course
not truly a matter of linguistic assimilation.]

But surely, the wary reader will object, there must be some relation
between language and culture, and between language and at least that
intangible aspect of race that we call "temperament". Is it not
inconceivable that the particular collective qualities of mind that have
fashioned a culture are not precisely the same as were responsible for
the growth of a particular linguistic morphology? This question takes us
into the heart of the most difficult problems of social psychology. It
is doubtful if any one has yet attained to sufficient clarity on the
nature of the historical process and on the ultimate psychological
factors involved in linguistic and cultural drifts to an