Laws of Nations, as far as
those principles are uncontradicted by modern opinion.

In the second instance, those differences which may either overrule,
add to, or complete the public opinion of a past age, are to be
ascertained, (by those in whose hands such decisions rest,) by looking
to the _wish_ of nations on these points; and this wish may be
exhibited in various ways; either by a universal abandonment of a
given law, in its non-execution by any nation whatever, for a length
of time; by numerous treaties, to obtain by convention an improvement
not yet declared by international tribunals; or by extending to the
relations and duties of nations, the improvements in the general
principles of right and justice, that are at the time being applied to
the concerns of private individuals.

The judges of such matters are not to ignore what is going on around
them; all necessary knowledge is to be brought into court to discover
what is the universal feeling of nations in respect of right and
wrong, at the time they decide, and if they see a departure from the
past sense of right and wrong, to make the modern, and not the
ancient, the fountain of modern law; thence deducing the modern rules.

Because a precept cannot be found to be settled by the consent or
practice of nations at one time, it is not to be concluded that it
cannot be incorporated into the public code of nations, at some
subsequent period. Nor is it to be admitted, that no precept belongs
to the law of nations which is not _universally_ recognised as such,
by all civilized communities, or even by those constituting what may
be called the Christian states of Europe. Some doctrines, which we, as
well as the United States, admit to belong to the Law of Nations, are
comparatively of recent origin and application, and even at this
period have received no public or general sanction in other nations;
and yet, inasmuch as they are founded on a just view of the duties and
rights of nations, according to a modern universal sense of what is
just, they are enforced here as ascertained laws.[1]

By a similar train of reasoning, not only may the international
tribunals of England enunciate new rules of law, as universal law, if
founded and fairly deduced from ascertained modern, public, and
international opinion; but they may refuse to alter settled rules,
however much opposed by other nations, provided those rules are still
deducible from that origin.

Generally, every