12 Conditions of historical comparison among ages and regions 273
of such a supra-regional motif is the expansion of the Oikoumeneic civi-
lizations. As civilizations gradually extended their sway, they brought
about changes in the "balance of power" between barbarism and the
cities,
so that by neither a common event, nor by direct interrelations, a
common effect was produced through the affecting of common condi-
tions.
The days of Attila differ from those of Genghis Khan in that in the
latter's day Central Asia was swamped with civilization: an added feel-
ing of nomadic vengeance combined with an immediate use of the full
techniques of civilization to make the Mongol conquest quite different
from the Hunnic, and productive of entirely different subsequent re-
sults.
Chinese, Europeans, and Iranians, even Indian Buddhists, had
combined quite unconsciously to make the whole continent a changed
place, with changed results. Similarly, by the time the Western Metamor-
phosis was under way it was only the more isolated regions of the
Hemisphere that had not been explored by Arabs or Chinese or Indians,
and to which the basic trade routes and means of exploitation had been
already opened up; one might hazard the guess that only in the second
half of the Second Millennium, when this was done, was the European
world conquest possible.
Similarly possessed of a supraregional quality is the cumulative prog-
ress that continues through thick and thin. In such times as the "Revi-
sion Period," in the early Byzantine Mediterranean Basin, there seems to
be little of a spectacular nature, yet the introduction of silk, the Diophan-
tine mathematics, and the continuous itemic improvements in
law,
medi-
cine,
and administration, religion and art, add up at last to the body of
material, possessed ultimately interregionally, on which such a move-
ment as the Islamic florescence, or the Western Metamorphosis, appear.
Indeed, many developments have an aspect that could be looked at in
this way. The rise of coinage throughout the zone in the first millennium
B.C., apparently in independence, changes the conditions of inter-
regional trade to a degree, at least indirectly, by its affects on internal
trade, at last directly; again, the problem of centralization faced and met
by so many separate governments at different times has its bearing on
the total course at last of interregional movements.
A convenient fourth type of motif is the activity
motif;
cases where a
particular activity involves interregional relationships. Good examples
here are the course of science, and the development of monastic ideals
insofar as the friars and dervishes, bikhus and fakirs impinged on one
another (even their pious emulation had its interfaith aspects): whether
monasticism begins in India or not, it is an activity common to many
areas,
with its particular and often intermingling carriers. Especially