ot 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 every
thing; 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 fortuitious concurrence of atoms. Three or four
brothers by blood, with a fourth or fifth man whom they agree to look on
as filling in every thing 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 every thing; 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 in this
way. Natural kindred was the groundwork, the leading and determining
idea; but, by one of those legal fictions which have had such an
influence on all institutions, adoption was in certain cases allowed to
count as natural kindred.[3]

The usage of all languages shows that community of blood was the leading
idea in forming the greater and smaller groups of mankind. Words like
[Greek: phylon, genos], _gens_, _natio_, _kin_, all point to the natural
family as the origin of all society. The family in the narrower sense,
the children of one father in one house, grew into a more extended
family, the _gens_. Such were the Alkmaionidai, the Julii, or the