THE POPULAR SCIENCE MONTHLY.
climate, soil, or atmosphere peculiar to the locality of the people professing and practicing those forms of religion. Consequently, the diversity of customs and habits of different peoples should give rise to rights and duties differing in nature and degree between the diverse political divisions. Now, what is the duty of a people in such cases in their relations with each other? It is the duty of a good father to love and protect the members of his family before other persons; his care and solicitude should begin with his own. Yet he owes a duty to his kind—that is, to help others when required, if he can do so without injury to himself or those depending on him. We may say that men in a state of nature would be compelled by force of circumstances to the observance of these rules. How is it with regard to states? Their first duty is to look to the welfare of their own citizens; yet they should remember that individuals of whatever nationality have natural and inherent rights that should be everywhere recognized, since the exercise of these rights is necessary to existence. It is true that an individual, passing from one state into another, can not carry with him rights not possessed by the citizens of the state he enters, especially if their exercise would interfere with the political or civil rights of the natives. Thus it is that rights will always vary from one people to another. Sometimes the laws and rights vary in the state itself; there frequently arises a diversity of laws and customs between the different provinces of the same country: as in ancient France, which was formed out of a number of feudal sovereignties, each having its particular law, and giving rise to frequent conflicts between different customs. A like cause produced a like effect in the German Empire: the law varied from one city to another, and even from one street to another in the same city. Another difficulty arises. How are we to determine between these conflicting laws? The law of nations is the same, theoretically at least, for all humanity. Private international law, which is a branch of the law of nations, has also a tendency to unity—not that it has for an ideal the uniformity of the law of all portions of the human race; such would be too dreamy an idea. But the rules which serve to solve these conflicts can and should be the same the world over, notwithstanding the diversity of legislation. It is this unity that private international law has sought, and now seeks to establish. How can it be realized? It can not be formed, like the civil law of each people, by legislation, or command of a superior authority, since independent sovereign nations recognize no authority superior to themselves. Each legislature can not make laws that will be operative beyond the limits of the territory over which it has legislative power. Here, again, we see the analogy between private international law and the law of nations. Nations, like individuals, have their personality; between individuals, the juridical disputes arise either upon a contract, or on account of a wrong committed; it is the same