no certain test of race;
but it is a presumption of race. Community of race, as we commonly
understand race, is no certain proof of original community of blood;
but it is a presumption of original community of blood. The
presumption amounts to moral proof, if only we do not insist on proving
such physical community of blood as would satisfy a genealogist. It
amounts to moral proof, if all that we seek is to establish a relation
in which the community of blood is the leading idea, and in which where
natural community of blood does not exist, its place is supplied by
something which by a legal fiction is looked upon as its equivalent.

If, then, we do not ask for scientific, for what we may call physical,
accuracy, but if we are satisfied with the kind of proof which is all
that we can ever get in the historical sciences--if we are satisfied to
speak in a way which is true for popular and practical purposes--then
we may say that language has a great deal to do with race, as race is
commonly understood, and that race has a great deal to do with
community of blood. If we once admit the Roman doctrine of adoption,
our whole course is clear. The natural family is the starting-point of
everything; but we must give the natural family the power of
artificially enlarging itself by admitting adoptive members. A group
of mankind is thus formed, in which it does not follow that all the
members have any natural community of blood, but in which community of
blood is the starting-point, in which those who are connected by
natural community of blood form the original body within whose circle
the artificial members are admitted. A group of mankind thus formed is
something quite different from a fortuitous concurrence of atoms.
Three or four brothers by blood, with a fourth or fifth man whom they
agree to look on as filling in everything the same place as a brother
by blood, form a group which is quite unlike a union of four or five
men, none of whom is bound by any tie of blood to any of the others.
In the latter kind of union the notion of kindred does not come in at
all. In the former kind the notion of kindred is the groundwork of
everything; it determines the character of every relation and every
action, even though the kindred between some members of the society and
others may be owing to a legal fiction and not to natural descent. All
that we know of the growth of tribes, races, nations, leads us to
believe that they grew