Identifying a Principle of International Law Today

In: The Canadian yearbook of international law: Annuaire canadien de droit international, Volume 11, p. 106-122

Abstract

The midwives of international law, Gentili, Grotius, Vitoria, Suarez, Pufendorf, and Wolff, found the principles of this law in the law of nature. This, in turn, was derived by some of them from the law of God and by others from the law of reason. But, as the law of nations grew and its content developed, its derivation was established, particularly with Vattel in the middle of the eighteenth century, from the will of states rather than from the law of nature. Today's international lawyer simply inherits the principle of identification whereby international-law rules of general application are created by international custom. (This custom is produced by that kind of practice of states relating to a matter of international relations which is concordant and general and is accompanied by the conviction of states that it is obligatory under international law.) The application of this principle of identification, however, is not so simple because of the appearance of three new situations.