A complete revolution in his ideas was required before it could challenge his respect, but so complete was it when it did occur, that the true reason why our modern estimate of the Jus Gentium differs from that which has just been described, is that both modern jurisprudence and modern philosophy have inherited the matured views of the later jurisconsults on this subject. There did come a time, when from an ignoble appendage of the Jus Civile, the Jus Gentium came to be considered a great though as yet imperfectly developed model to which all law ought as far as possible to conform. This crisis arrived when the Greek theory of a Law of Nature was applied to the practical Roman administration of the Law common to all Nations. The Jus Naturale, or Law of Nature, is simply the Jus Gentium or Law of Nations seen in the light of a peculiar theory. An unfortunate attempt to discriminate them was made by the jurisconsult Ulpian, with the propensity to distinguish characteristic of a lawyer, but the language of Gaius, a much higher authority, and the passage quoted before from the Institutes leave no room for doubt, that the expressions were practically convertible. The difference between them was entirely historical, and no distinction in essence could ever be established between them. It is almost unnecessary to add that the confusion between Jus Gentium, or Law common to all Nations, and _international law_ is entirely modern. The classical expression for international law is Jus Feciale or the law of negotiation and diplomacy. It is, however, unquestionable that indistinct impressions as to the meaning of Jus Gentium had considerable share in producing the modern theory that the relations of independent states are governed by the Law of Nature.