ot always be
deduced, positive human enactments are necessary to define the law of
nature and revelation. So an important part of the law of nations
necessarily consists of positive institutions. Hence some writers have
divided international law under these two principal heads: the _natural_
law of nations, and the _positive_.

Sec.11. The _positive law of nations_ is founded on usage or custom and
agreement, and may be considered as properly divided into the
_customary_ law of nations, and the _conventional_. The _customary law
of nations_ consists of certain maxims, or is founded on customs and
usages which have been long observed and tacitly consented to by
nations, and have thereby become binding upon all who have adopted them,
so far as their observance does not require a violation of the law of
nature.

Sec.12. A _conventional law of nations_ is one that has been established by
a treaty or league. The word _convention_ usually signifies an assembly
of persons met for some benevolent, political, or ecclesiastical
purpose. It also signifies a treaty, or agreement between nations; and
such agreement or contract, though made without a formal meeting, is
deemed conventional.

Sec.13. As the law of nature is liable to misconstruction, and as the law
of usage or custom is vague and uncertain, _conventional_ law, because
more definite, has been found to afford greater security to the rights
of commerce. Hence the practice, now so common among nations, of
regulating their intercourse by negotiation. By treaties, the rights of
the contracting parties are placed beyond dispute.

Sec.14. But it may be said, if each nation is independent of every other,
and if there is no constituted authority to enforce the fulfillment of
treaty stipulations, the rights guarantied by treaties are still
insecure. But few governments are so devoid of a sense of honor as, by a
palpable violation of treaty obligations, to incur the odium and
condemnation of all mankind. Self-respect and the fear of provoking a
war, have generally proved sufficient incentives to the observance of
treaties.

Sec.15. The obligations of nations are sometimes called _imperfect_. A
_perfect obligation_ is one that can be enforced--one that exists where
there is a right to compel the party on whom the obligation rests to
fulfill it. An _imperfect obligation_ gives only the right to demand the
fulfillment, leaving the party pledged to judge what his duty requires,