the obligation of a contract has its
origin in the law of a particular State, and is in all cases what that
law makes it, and no more, and no less, we shall probably find ourselves
involved in inextricable difficulties. A man promises, for a valuable
consideration, to pay money in New York. Is the obligation of that
contract created by the laws of that State, or does it subsist
independent of those laws? We contend that the obligation of a contract,
that is, the duty of performing it, is not created by the law of the
particular place where it is made, and dependent on that law for its
existence; but that it may subsist, and does subsist, without that law,
and independent of it. The obligation is in the contract itself, in the
assent of the parties, and in the sanction of universal law. This is the
doctrine of Grotius, Vattel, Burlamaqui, Pothier, and Rutherforth. The
contract, doubtless, is necessarily to be enforced by the municipal law
of the place where performance is demanded. The municipal law acts on
the contract after it is made, to compel its execution, or give damages
for its violation. But this is a very different thing from the same law
being the origin or fountain of the contract.

Let us illustrate this matter by an example. Two persons contract
together in New York for the delivery, by one to the other, of a
domestic animal, a utensil of husbandry, or a weapon of war. This is a
lawful contract, and, while the parties remain in New York, it is to be
enforced by the laws of that State. But if they remove with the article
to Pennsylvania or Maryland, there a new law comes to act upon the
contract, and to apply other remedies if it be broken. Thus far the
remedies are furnished by the laws of society. But suppose the same
parties to go together to a savage wilderness, or a desert island,
beyond the reach of the laws of any society. The obligation of the
contract still subsists, and is as perfect as ever, and is now to be
enforced by another law, that is, the law of nature; and the party to
whom the promise was made has a right to take by force the animal, the
utensil, or the weapon that was promised him. The right is as perfect
here as it was in Pennsylvania, or even in New York; but this could not
be so if the obligation were created by the law of New York, or were
dependent on that law for its existence, because the laws of that State
can have no operation beyond its territory. Let us reverse this example.
S