nsanguinity, and unless it be proved that age grades are a product of
the period of "group marriage" it cannot be argued that they ever did
imply kinship.

It is sufficiently clear from these examples that Morgan entirely failed
to work out the process by which the transition from pure to regulated
promiscuity came about. But if the process is uncertain the causes are
equally obscure. In Mr Morgan's view, or at any rate in one of the
theories on which he accounted for the change, it was due to "movements
which resulted in unconscious reformation"; these movements were, he
supposes, worked out by natural selection. These words, it is true,
apply primarily to the origin of the "tribal" or "gentile" organisation,
as Mr Morgan terms totemism, but they probably apply to the original
passage from promiscuity to "communal marriage," and I propose to
examine how far such a theory has any solid basis.

Natural selection is a blessed phrase, but in the present case it is
difficult to see in what way it is supposed to act. The variation
postulated by Mr Morgan as a basis for the operation of natural
selection is one of ideas, not physical or mental powers. Now under
ordinary circumstances we mean by natural selection the weeding out of
the unfit by reason of inferiorities, physical or psychical, which
handicap them in the struggle for existence. But it cannot be said that
the tendency to marry or practice of marrying outside one's own
generation is such a handicap to the parents. How far is it injurious to
the children of such unions? Or rather, how far have children who are
the offspring of brothers and sisters or of cousins a better chance of
surviving than the offspring of unions between relatives of different
generations?

It is at the outset clear that savages are not in the habit of taking
account of such matters. Even if it were otherwise, it is not clear how
far they would have data as to the varying results of unions of near
kin. For though on this question, so far as the genus homo is concerned,
we have very few data on which to go, such data as we have hardly bear
out his view. Modern statistics relate almost exclusively to the
intermarriage of cousins, and apply, not to primitive tribes, such as
those with which, _ex hypothesi_, Mr Morgan is dealing, but to more or
less civilised and sophisticated peoples, among whom the struggle for
existence is less keen owing to the advance of knowledge and the
progress of invent