rganization; social organization on numbers; numbers on food; and
food on invention. Here both ends of the series are represented by
spiritual factors--namely, culture at the one end, and invention at
the other. Amongst the intermediate links, food and numbers may be
reckoned as physical factors. Social organization, however, seems to
face in both directions at once, and to be something half-way between
a spiritual and a physical manifestation.

In placing invention at the bottom of the scale of conditions, I
definitely break with the opinion that human evolution is throughout
a purely "natural" process. Of course, you can use the word "natural"
so widely and vaguely as to cover everything that was, or is, or could
be. If it be used, however, so as to exclude the "artificial," then
I am prepared to say that human life is preeminently an artificial
construction, or, in other words, a work of art; the distinguishing
mark of man consisting precisely in the fact that he alone of the
animals is capable of art.

It is well known how the invention of machinery in the middle of the
eighteenth century brought about that industrial revolution, the
social and political effects of which are still developing at this
hour. Well, I venture to put it forward as a proposition which applies
to human evolution, so far back as our evidence goes, that history
is the history of great inventions. Of course, it is true that climate
and geographical conditions in general help to determine the nature
and quantity of the food-supply; so that, for instance, however much
versed you may be in the art of agriculture, you cannot get corn to
grow on the shores of the Arctic sea. But, given the needful inventions,
superior weapons for instance, you need never allow yourselves to be
shoved away into such an inhospitable region; to which you presumably
do not retire voluntarily, unless, indeed, the state of your arts--for
instance, your skill in hunting or taming the reindeer--inclines you
to make a paradise of the tundra.

Suppose it granted, then, that a given people's arts and inventions,
whether directly or indirectly productive, are capable of a certain
average yield of food, it is certain, as Malthus and Darwin would remind
us, that human fertility can be reckoned on to bring the numbers up
to a limit bearing a more or less constant ratio to the means of
subsistence.

At length we reach our more immediate subject--namely, social
organization. I