effective responses to new situations (which is almost a definition of
intelligence). If we ask what makes a creative individual, we are thrown
back from history to psychology and biology–to the influence of
environment and the gamble and secret of the chromosomes. In any case a
challenge successfully met (as by the United States in 1917, 1933, and
1941), if it does not exhaust the victor (like England in 1945), raises the
temper and level of a nation, and makes it abler to meet further challenges.
If these are the sources of growth, what are the causes of decay? Shall
we suppose, with Spengler and many others, that each civilization is an
organism, naturally and yet mysteriously endowed with the power of
development and the fatality of death? It is tempting to explain the behavior
of groups through analogy with physiology or physics, and to ascribe the
deterioration of a society to some inherent limit in its loan and tenure of
life, or some irreparable running down of internal force. Such analogies
may offer provisional illumination, as when we compare the association of
individuals with an aggregation of cells, or the circulation of money from
banker back to banker with the systole and diastole of the heart. But a
group is no organism physically added to its constituent individuals; it has
no brain or stomach of its own; it must think or feel with the brains or
nerves of its members. When the group or a civilization declines, it is
through no mystic limitation of a corporate life, but through the failure of
its political or intellectual leaders to meet the challenges of change.
The challenges may come from a dozen sources, and may by repetition
or combination rise to a destructive intensity. Rainfall or oases may fail and
leave the earth parched to sterility. The soil may be exhausted by
incompetent husbandry or improvident usage. The replacement of free with
slave labor may reduce the incentives to production, leaving lands untilled
and cities unfed. A change in the instruments or routes of trade–as by the
conquest of the ocean or the air–may leave old centers of civilization
becalmed and decadent, like Pisa or Venice after 1492. Taxes may mount to
the point of discouraging capital investment and productive stimulus.
