To the extent that they concern issues of an international character, general principles of law, like rules of customary international law, can serve to protect and encourage the common interests of most if not all States. One of the clearest materializations of a State's interests may be how it controls itself and its citizens through its own national laws.
If one State's national laws were to specify that State's particular interests, the national laws of all States might, in so far as they concerned an issue of an international character, collectively give a reasonable indication of the common interests of most, if not all, of the members of the international society of States.
Since national laws have long played a task in the customary process as instances of relevant State practice, looking to national laws to establish whether most States have a common interest in jus cogens rules would appear to be consistent with jus cogens rules being rules of customary international law (Fox, Gregory and Georg Noltem, 1995). Opposed to the Naturalists is the other school of international law writers, known as the Positivists.
They not only attack the existence of a positive law of nations resulting from custom and treaties, but provided such positive law precedence over any principles that can be derived from the natural law of nations. The Positivists constituted a large and increasing school of writers. Their leaders in the seventeenth century were two German writers, Rachel and Textor. The former published two dissertations in 1676 entitled De Jure Naturae et Gentium, in which he defines the law of nations as the law to which a plurality of free states are subjected, and which comes into existence through the tacit or express assent of these states.
In the nineteenth century the debate between the Naturalists and the Positivists became heated in England. Richard Wildman, of London, who wrote on the nature and sources of international law in 1849, denied positively that the law of nature forms any part of international law. He says: “The term is borrowed from the Roman lawyers. . . . The law of nature in its contemporary signification means nothing more than natural justice and equity, or the rules of theoretical propriety. This was one of its significations in the Roman law. . .
It is observable that such rules can inflict no legal obligations until they are sanctioned by usage or legislative authority, and thus pass into law. Wanting that authorize they bear, when applied to international transactions, the same relation to international law that the duties of private charity bear to the compulsions of municipal law. They are fit to inform the conscience of statesmen, but not to define international rights” (Wildman, 1849, pp. 2-4). A directly opposite view was expressed in 1883 by James Lorimer, a Scotchman, who defined international law as “the law of nature recognized in the relations of separate nations.
" He explained his point of view by stating his "anxiety to place international law on deeper and more established foundations than comity or convention and to indicate for international jurisprudence the nature of a science of nature which I have elsewhere claimed for jurisprudence as a whole"(Lorimer, 1883, pp. vii, 1). Passing from theory and philosophical thought to the records of history, we are learned that while the curtain rises which conceals the dark, prehistoric past, we see fighting everywhere over the earth.
The great kingdoms of ancient times were at war either amongst themselves or with the wild hordes descending from the austere north upon the lands of sunshine and wealth; the tribes of northern Europe were always at war with one another, or about the Mediterranean Sea the Greek states were inconstant conflict. The same conditions of natural antagonism were true of the aborigines in Africa and of the Americas while they were discovered by the white man (Bryce, 1922, pp. 6 – 7).