44 Law and Morality Abroad (to ca. ad 1550)On a slightly more down- to- earth note, some stoic writers thought that
the world had witnessed concrete steps in the direction of the realization of
the ideal of the world as a single city. Alexander the Great was sometimes
hailed (most memorably by Plutarch) as being inspired by such a vision.
Th is claim would appear to have been exaggerated by a considerable mar-
gin. But it was not diffi cult to see, in the course of Mediterranean history,
some trends that could clearly be interpreted in terms of stoic philosophy.
One of these was the gradual decline of the in de pen dent city- states and their
incorporation into ever larger groupings, fi rst with the conquests of Alexan-
der in the fourth century bc, and then with the unifi cation of the Mediter-
ranean world by Rome.
We must take care not to regard the stoics as champions of anything that
we would today call international law. Th ey are much more accurately seen
as champions of world government, in their insistence on the ultimate unity
of the human race into a single polity. In this, they bore a resemblance to the
imperial Chinese— though with the diff erence that, where the Chinese saw
the world as (ideally) one single grand cultural system, the stoics regarded it
as one single great natural system. Th e stoic vision, in other words, did not
accord any inherently privileged position to Greek or Roman culture and
could therefore be said to be more radically cosmopolitan in character than
its Chinese counterpart.
For present purposes, though, two other aspects of their thought are worth
emphasizing, which would play a powerful role in the later development of
Eu ro pe an thought— including the development of international law. One
was the universality of natural law. Natural law, on this thesis, was a compre-
hensively transcultural concept, applicable in full force to every culture and
civilization on earth. Moreover— and this is the second key feature— natural
law was the same for all historical time periods as well. It was, in short, eter-
nal as well as universal.
Rome and the Ius gentium
It was Rome, more than any other ancient society, that bequeathed a set of
ideas that would later metamorphose into international law in the later sense
of that term. To some extent, their thinking was borrowed (as usual) from