[73]. Fundamenta Juris Nat. et Gent. I. 5. 67.
[74]. De Jure Nat. et Gent. II. 3. 23.
[75]. Principes du droit de la nature et des gens, vol. iv. p. 16, ed. 1820.
[76]. It is maintained by such writers as Hall, Rivier, Bluntschli, Nys, Sidgwick, Westlake, Walker, Lawrence, and Oppenheim.
[77]. “The sole source of (international) law,” says Dr. Walker in his History of International Law, vol. i. p. 21, “is actual observance.” This law, he adds, p. 31, is “the embodiment of state practice.” It is not easy to make a list of the genuine adherents of this opinion, because so many writers introduce vagueness and uncertainty into their exposition by speaking of international consent as well as of international practice as a source of law; and they fail to make it clear whether such practice is operative per se, or only as evidence of underlying consent. Moreover, the word consent is itself used ambiguously and vaguely, and it is often difficult to know whether it means international agreement, or international opinion, or the harmonious practice of states.
[78]. I. p. 187.
[79]. See Westlake, International Law, p. 7; Chapters on the Prls. of Int. Law, p. 2; Hall, Int. Law, p. 1; Sidgwick, Elements of Politics, Ch. 17. pp. 274 sqq. 1st ed.; Oppenheim, International Law, I. § 5.
[80]. Jeremy Taylor’s Works, XIII. 306, Heber’s ed.
[81]. Hobbes’ Leviathan, ch. 13: “Hereby it is manifest that during the time men live without a common power to keep them all in awe, they are in that condition which is called war; and such a war as is of every man against every man.... Whatsoever therefore is consequent to a time of war, where every man is enemy to every man, the same is consequent to the time wherein men live without other security than what their own strength and their own invention shall furnish them withal. In such condition there is no place for industry ... no arts, no letters, no society, and, which is worst of all, continual fear and danger of violent death; and the life of man, solitary, poor, nasty, brutish, and short.”
[82]. Treatise on Government, II. ch. 2.