Grotius, I. c. 1, § 2--Vattel, III. §§ 1-4, 69-72--Hall, §§ 15-18--Westlake, II. pp. 1-6--Lawrence, § 135--Lorimer, II. pp. 18-28--Manning, pp. 131-133--Phillimore, III. § 49--Twiss, II. §§ 22-29--Taylor, §§ 449-451--Wheaton, § 295--Bluntschli, §§ 510-514--Heffter, §§ 113-114--Lueder in Holtzendorff, IV. pp. 175-198--Klüber, §§ 235-237--G. F. Martens, II. § 263--Ullmann, § 165--Bonfils, Nos. 1000-1001--Despagnet, Nos. 499-505--Pradier-Fodéré, VI. Nos. 2650-2660--Rivier, II. § 61--Nys, III. pp. 95-117--Calvo, IV. §§ 1860-1864--Fiore, III. Nos. 1232-1268--Martens, II. § 106--Westlake, _Chapters_, pp. 258-264--Heilborn, _System_, pp. 321-332--Rettich, _Zur Theorie und Geschichte des Rechts zum Kriege_ (1888), pp. 3-140--Wiesse, _Le Droit international appliqué aux guerres civiles_ (1898)--Rougier, _Les guerres civiles et le droit des gens_ (1903)--Higgins, _War and the Private Citizen_ (1912), pp. 3-72. [Sidenote: War no illegality.] § 53. As within the boundaries of the modern State an armed contention between two or more citizens is illegal, public opinion has become convinced that armed contests between citizens are inconsistent with Municipal Law. Influenced by this fact, impatient pacifists, as well as those innumerable individuals who cannot grasp the idea of a law between Sovereign States, frequently consider war and law inconsistent. They quote the fact that wars are frequently waged by States as a proof against the very existence of an International Law. It is not difficult to show the absurdity of this opinion. As States are Sovereign, and as consequently no central authority can exist above them able to enforce compliance with its demands, war cannot, under the existing conditions and circumstances of the Family of Nations, always be avoided. International Law recognises this fact, but at the same time provides regulations with which belligerents have to comply. Although with the outbreak of war peaceable relations between the belligerents cease, there remain certain mutual legal obligations and duties. Thus war is not inconsistent with, but a condition regulated by, International Law. The latter at present cannot and does not object to States which are in conflict waging war upon each other instead of peaceably settling their difference. But if they choose to go to war they have to comply with the rules laid down by International Law regarding the conduct of war and the relations between belligerents and neutral States. That International Law, if it could forbid war altogether, would be a more perfect law than it is at present there is no doubt. Yet eternal peace is an impossibility in the conditions and circumstances under which mankind at present live and will have to live for a long time to come, although eternal peace is certainly an ideal of civilisation which will slowly and gradually be realised. [Sidenote: Conception of War.]