intermediate groupings, but the historical process has by no means
conformed at all exactly to this logical order. Society has not been
made in orderly fashion by forming families and then combining families
to make hundreds, and hundreds to make counties, and counties nations,
and so on to the whole. A German god might have done this, but the way
of nature and history was less perfect. The minor forms of human
association have been taking shape, being altered and on the whole
improved, throughout the process. At one point, of high importance for
our argument, a larger form of association was achieved before the
necessary constituent elements were articulated. This was the
Greco-Roman world encircling the Mediterranean and completed in the
Roman Empire of the second century A.D. It was the nucleus from which
the Western world of modern civilization has been developed; yet it was
there, settled in its main outlines, before the national units which it
required for internal harmony and cohesion had taken any definite shape.
It is to the difficulties of their growth and mutual adjustment that we
owe most of the conflicts of modern history.

We shall in this book go back first to a still earlier stage, a stage of
pre-history, to a time when no one, not gifted with superhuman insight
and prescience, could have foreseen the course which human civilization
would pursue. All over the world, for tens of thousands of years, a
culture persisted, associated with stone implements, and marked by a
similarity which is often extremely striking, in races and tribes widely
severed by distance and climatic conditions. The raw material of the
human product in science, art, and invention was alike in texture
although often exuberant in detail and imagination. But it had not yet
the unity of an organic whole, knit by a common purpose and conscious of
itself.