cannot help speaking a particular language, this simply means that his
circumstances are such that no other way of speaking presents itself to
his mind. And in many cases, he has a real choice between two or more
ways of speaking; that is, between two or more languages. Every word
that a man speaks is the result of a real, though doubtless unconscious,
act of his free will. We are apt to speak of gradual changes in
language, as in institutions or any thing else, as if they were the
result of a physical law, acting upon beings who had no choice in the
matter. Yet every change of the kind is simply the aggregate of various
acts of the will on the part of all concerned. Every change in speech,
every introduction of a new sound or a new word, was really the result
of an act of the will of some one or other. The choice may have been
unconscious; circumstances may have been such as practically to give him
but one choice; still he did choose; he spoke in one way, when there was
no physical hindrance to his speaking in another way, when there was no
physical compulsion to speak at all. The Gauls need not have changed
their own language for Latin; the change was not the result of a
physical necessity, but of a number of acts of the will on the part of
this and that Gaul. Moral causes directed their choice, and determined
that Gaul should become a Latin-speaking land. But whether the skulls of
the Gauls should be long or short, whether their hair should be black or
yellow, those were points over which the Gauls themselves had no direct
control whatever.

The study of men's skulls then is a study which is strictly physical, a
study of facts over which the will of man has no direct control. The
study of men's languages is strictly an historical study, a study of
facts over which the will of man has a direct control. It follows
therefore from the very nature of the two studies that language cannot
be an absolutely certain test of physical descent. A man cannot, under