Western civilization possesses a certain unity (1) in the sense of unity
of character, (2) in the fact that it has a common origin, ultimately in
the Greco-Roman civilization but more immediately in mediaeval
Christendom, and (3) in the sense that its parts have maintained a
constant intercommunication of ideas. (4) The different qualities of
German, French, and English thinkers have in large measure complemented
one another, (5) and the history of science and of speculative
philosophy is largely a history of the interaction of distinct national
schools. (6) The same thing is true of political thought. (7) Thus the
world of thought forms a commonwealth which is superior to all national
differences and, in spite of the war, remains a foundation of a very
genuine unity.