two lines of Empedocles descanting on Universal Law. So Demosthenes refers to the common law of all mankind' which justifies a man in defending his property by force 1.

The Stoics took up the idea and worked it out with great fullness and force, especially on its ethical side. They developed the Aristotelian conception of Nature as the guiding principle immanent in the universe. This principle is Reason, i.e. the Divine Reason; and Natural or Common (=Universal) Law is its expression. So also in Man, who is a part of universal nature, Reason is the ruling and guiding element, ordering all his faculties in such wise that when they are rightfully developed in action he is obeying his true nature. Thus the formula 'to live according to nature' becomes the concise statement of what is at once his duty and his happiness.

Philosophers were however by no means unanimous. on the subject. The Sceptics and the New Academics denied altogether that there was such a thing as the 'naturally just (púσa díkαuov),' pointing to the diversities in the positive law of all States, and also to the disagreements among speculative thinkers. But the Socratic or Aristotelian or Stoic view prevailed, having ethical or religious considerations to recommend it to those who greatly desired to find an ethical basis for life, and, if possible, create thereout a religion.

What I have called the Political form of the idea is to be found in the notion, as old as Epicurus, that there is a close connexion between the Law of Nature and the Common Good, a connexion sometimes represented by saying that Natural Justice prescribes what is useful for all, sometimes by holding that practical utility is the test of whether any law is to be deemed to have the authority of Nature behind it 2. This notion comes right down through the ancient world to modern times,

1 Against Aristocrates, 639.

2 Epicurus described Natural Justice as an agreement made for the sake of common advantage: τὸ τῆς φύσεως δίκαιον ἔστι σύμβολον τοῦ συμφέροντος εἰς τὸ μὴ βλάπτειν ἀλλήλους μηδὲ βλάπτεσθαι (Diog. Laert. x. 150).

and is really implicit in nearly all that has been written on the subject. No one would have repudiated the high metaphysical or theological view of the Law of Nature more vigorously than Bentham, yet there is an affinity between his method of applying utility as against positive laws and the methods of several of the ancient philosophers. And so a German critic is justified when he talks of Bentham and Austin as the 'propounders of theories of Natural Law.' With the political outcome of the idea, however, we are not at this moment concerned. It is enough to indicate how it has found expression in these various fields 1.

What I have sought to do in this introductory statement is to show how the notion of Nature as a force governing social as well as physical phenomena grew up, and to indicate the wide influence it had attained at the time when Rome became mistress of the world. Let us now turn to the Romans, and inquire what they meant by Natural Law, how the conception shaped itself in their hands, and to what practical use they turned it.

The Roman conception has two sources, the one historical, the other theoretical. I begin with the historical, which is the earlier in date, and incomparably the more important 2.

1 Since this Essay was in type I have seen the article On the History of the Law of Nature, by Sir F. Pollock, published in the Journal of the Society of Comparative Legislation for Dec. 1900, and simultaneously in the Columbia Law Review, Jan. 1901; and am happy to find myself in substantial agreement with him upon all points of importance connected with the subject. Some branches of it, especially the Greek and mediaeval parts of the history of the idea, are treated of more fully by him, and the whole article is full of interest. Judicious remarks and useful quotations will also be found in Prof. D. G. Ritchie's Natural Rights (published in 1895), Part i; and in Dr. Holland's Elements of Jurisprudence, pp. 30-38 of ninth edition.

2 A very minute and careful collection of the authorities regarding Ius Naturae and Ius Gentium may be found in the book of Dr. Moriz Voigt, Die Lehre vom Jus Naturale, aequum et bonum und Jus Gentium der Römer. I do not find myself always able to agree with his views, but they are stated with painstaking ability, and the citations have often aided me.

III. THE ROMAN LAW OF THE NATIONS.'

Long before the time when the city on the Tiber had become the undisputed mistress of Italy, Rome began to be the resort of many strangers who did not possess even that qualified kind of citizenship (summed up in the words connubium and commercium) which included the capacity for forming family ties, and for entering into business relations according to Roman rules. These strangers or aliens (peregrini) had originally no civil rights, public or private, but they nevertheless dealt with Roman citizens, sold to them, bought from them, lent and borrowed money, entered into partnership, acted as factors or supercargoes, made wills, gave or received legacies. Similarly, some of them contracted marriages with Roman citizens, and became connected by various family bonds. It was necessary for the Roman courts to deal with the relations, and especially of course with the business relations, which were thus created. Yet the courts could not apply the rules of pure Roman law to them, because it was a precondition to the doing of certain formal acts under that law, to the holding certain legal relations, and (in some kinds of suits) to the use of the appropriate forms of procedure, that the doer or holder should be a full citizen. Accordingly the Roman courts, when they had to administer justice between these strangers, or between them and citizens, were obliged to find certain principles and rules which could guide their action in the same way as the principles and rules of the pure Roman law guided them when dealing with citizens.

The phenomenon of having a different law for strangers and for citizens is one which at first sight seems strange to us moderns, because in modern civilized countries ordinary private law is administered with little regard to the nationality or allegiance of the persons concerned, the law of the country being regularly applied, except when it can be shown that the domicil of a party

to a suit, or the fact that a contract was made with reference to another law than that of the court exercising jurisdiction, or the situation of the property dealt with, requires the application of some other (i.e. foreign) law1. But in the ancient world foreigners everywhere stood on a different level from citizens, as regards not only political, but also private civil rights; the sense of citizenship being much more intense in small communities, and there being no such bond of fellowship as the Christian Church subsequently formed for the Middle Ages and the modern world 2. Indeed it was the Roman Empire and the Church taken together which first created the idea of a law common to all subjects and (later) to all Christians, a law embodying rights enforceable in the courts of every civilized country.

How then did the Roman magistrates find the law which they needed for the above-mentioned purpose? As they could not apply their own law, so neither could they select the law of any one of the States which surrounded Rome, because the persons between whom justice had to be done came from a great number of States and tribes, each of which had a law of its own. Being unable therefore to borrow, they were forced to create. They would appear to have created-I say 'appear,' because our knowledge of the matter is far from complete by taking those general principles of justice, fair dealing, and common sense, which they found recognized by other peoples as well as their own, and by giving effect to those mercantile and other similar usages which they found prevailing among the strangers resident at Rome. Thus by degrees they built up a body of rules and a system of legal procedure which, while it resem

1 In the days after the fall of the Roman Empire, however, different laws were applied to different sets of persons in the extra-European dominions of European States, e.g. the Roman law to the clergy and the provincial subjects, the barbarian law to barbarians. And the same thing happens now in countries where Europeans and Musulmans or semi-civilized tribes dwell side by side.

3 Among some of the Greek cities, however, before they were engulfed in the Roman dominion, there had grown up a practice by which friendly commonwealths reciprocally extended certain civil rights to one another's citizens.

bled their own system in many of its general features, was less technical and more consonant to the practical convenience and general understanding of mankind. They called it the Law of the Nations or of Mankind (ius gentium) 1, not in the sense of law valid as between nations (what we should call International Law 2), but as being the common or general law, just as the expression nusquam gentium means nowhere at all 3. It is the law which nations in general used and could comprehend. Each of these nations, or communities-Tuscans, Umbrians, Greek cities of Southern Italy, Carthaginians, and so forth-had a law of its own, with certain peculiarities which no other people could be expected to know or perhaps to relish. But the principles of good faith and equity underlay, and were recognized in, the laws of all, so that this Law of the Nations represented the common element which all shared, and by which all might be content to be judged. Thus it comes near to what the Greeks had called the common law of mankind.' Yet it is not to be identified with that law, for it is conceived of as something concrete, resting entirely on the fact that men observe it, and possibly not always in accordance with abstract justice.

We need not here examine the question, which indeed our data do not enable us to answer, by what practical methods or processes the Roman Courts proceeded to frame this Law of the Nations; whether, and if so how

1 The word gens, though we commonly translate it ‘nation,' was originally used to denote a clan or sept (e.g. Fabii, Julii), and always retained this as one of its meanings. Can this original sense have had anything to do with the earliest legal meaning of the term? One is tempted to conjecture that there might have been a sort of common law of the gentes, recognized in contradistinction to the law of each gens, but when we find the term in the time of Cicero, it has the sense mentioned in the text, and I do not know of any facts supporting such a conjecture. So far back as one can go ius Quiritium is the term applied to the law of the city as a whole.

Though ius gentium is sometimes the term used to describe those usages which as being common to all men were in fact observed by States in their relation to one another; cf. Sallust, Jug. c. 35; Livy, i. 14; v. 36. Obviously the rules which all nations recognize would be those which they would apply in their dealings with one another.

* See the article Ius Gentium in Professor H. Nettleship's Contributions to Latin Lexicography. He thinks the term had become a popular one before the time of Cicero.