it appears as if the moment a number of _units_ were
acknowledged to obey no common sovereign or political superior they
were thrown back on the ulterior behests of the Law Natural. States
are such units; the hypothesis of their independence excludes the
notion of a common lawgiver, and draws with it, therefore, according
to a certain range of ideas, the notion of subjection to the primeval
order of nature. The alternative is to consider independent
communities as not related to each other by any law, but this
condition of lawlessness is exactly the vacuum which the Nature of the
jurisconsults abhorred. There is certainly apparent reason for
thinking that if the mind of a Roman lawyer rested on any sphere from
which civil law was banished, it would instantly fill the void with
the ordinances of Nature. It is never safe, however, to assume that
conclusions, however certain and immediate in our own eyes, were
actually drawn at any period of history. No passage has ever been
adduced from the remains of Roman law which, in my judgment, proves
the jurisconsults to have believed natural law to have obligatory
force between independent commonwealths; and we cannot but see that to
citizens of the Roman empire who regarded their sovereign's dominions
as conterminous with civilisation, the equal subjection of states to
the Law of Nature, if contemplated at all, must have seemed at most an
extreme result of curious speculation. The truth appears to be that
modern International Law, undoubted as is its descent from Roman law,
is only connected with it by an irregular filiation. The early modern
interpreters of the jurisprudence of Rome, misconceiving the meaning
of Jus Gentium, assumed without hesitation that the Romans had
bequeathed to them a system of rules for the adjustment of
international transactions. This "Law of Nations" was at first an
authority which had formidable competitors to strive with, and the
condition of Europe was long such as to preclude its universal
reception. Gradually, however, the western world arranged itself in a
form more favourable to the theory of the civilians; circumstances
destroyed the credit of rival doctrines; and at last, at a peculiarly
felicitous conjuncture, Ayala and Grotius were able to obtain for it
the enthusiastic assent of Europe, an assent which has been over and
over again renewed in every variety of solemn engagement. The great
men to whom its triumph is chiefly owing attempted, i