further and still more interesting question why some few nations
progress, and why the greater part do not.

Of course at first all such distinctions of nation and nation were
explained by original diversity of race. They ARE dissimilar, it was
said, because they were created dissimilar. But in most cases this
easy supposition will not do its work. You cannot (consistently with
plain facts) imagine enough original races to make it tenable. Some
half-dozen or more great families of men may or may not have been
descended from separate first stocks, but sub-varieties have
certainly not so descended. You may argue, rightly or wrongly, that
all Aryan nations are of a single or peculiar origin, just as it was
long believed that all Greek-speaking nations were of one such
stock. But you will not be listened to if you say that there were
one Adam and Eve for Sparta, and another Adam and Eve for Athens.
All Greeks are evidently of one origin, but within the limits of the
Greek family, as of all other families, there is some contrast-
making force which causes city to be unlike city, and tribe unlike
tribe.

Certainly, too, nations did not originate by simple natural
selection, as wild varieties of animals (I do not speak now of
species) no doubt arise in nature. Natural selection means the
preservation of those individuals which struggle best with the
forces that oppose their race. But you could not show that the
natural obstacles opposing human life much differed between Sparta
and Athens, or indeed between Rome and Athens; and yet Spartans,
Athenians, and Romans differ essentially. Old writers fancied (and
it was a very natural idea) that the direct effect of climate, or
rather of land, sea, and air, and the sum total of physical