nderstanding, we may obtain a broad conception of the
way in which the earth and its living inhabitants came to be what they
are. No one is more conscious than the writer that this account is
extremely imperfect. The limits of the volume have permitted me to use
only a part of the material which modern science affords, but if the
whole of our discoveries were described the sketch would still remain
very imperfect. The evolutionary conception of the world is itself
undergoing evolution in the mind of man. Age by age the bits of fresh
discovery are fitted into the great mosaic. Large areas are still
left for the scientific artist of the future to fill. Yet even in
its imperfect state the evolutionary picture of the world is most
illuminating. The questions that have been on the lips of thoughtful men
since they first looked out with adult eyes on the panorama of nature
are partly answered. Whence and Why are no longer sheer riddles of the
sphinx.

It remains to be seen if evolutionary principles will throw at least an
equal light on the progress of humanity in the historical period.
Here again the questions, Whence and Why, have been asked in vain for
countless ages. If man is a progressive animal, why has the progress
been confined to some of the race? If humanity shared at first a common
patrimony, why have the savages remained savages, and the barbarians
barbaric? Why has progress been incarnated so exceptionally in the white
section of the race, the Europeans? We approach these questions more
confidently after surveying the story of terrestrial life in the light
of evolutionary principles. Since the days of the primeval microbe it
has happened that a few were chosen and many were left behind. There was
no progressive element in the advancing few that was not shared by the
stagnant many. The difference lay in the environment. Let us see if this
principle applies to the history of civilisation.

In the last chapter I observed that, with the rise of human
intelligence, the cultural environment becomes more important than the
physical. Since human progress is a progress in ideas and the emotions
which accompany them, this may seem to be a truism. In point of fact it
is assailed by more than one recent historical writer. The scepticism
is partly due to a misunderstanding. No one but a fanatical adherent of
extreme theories of heredity will deny that the physical surroundings of
a race continue to be of great importance. T