that it may have entered into the Stoic philosophy in some vague way. We find it in the lawyers of the third century. Ulpian says: "In civil law, slaves are considered null. Not, however, by natural right; because, as regards natural right, all men are equal." And Florentinus: "Liberty is the natural faculty of that which it is permitted to any one to do, unless something has been prohibited to him by force or law. Slavery is an institution of the law of nations, by which any one is subjected to the rule of another, against nature. Servi are so called because military commanders are wont to sell captives, and so to preserve (servare) them and not kill them." The doctrine, therefore, gets into the Institutes of Justinian: "Slavery is the institute of the law of nations by which a human being is subjected to another's control against nature." These propositions, however, in the law, remained entirely barren, and were not different from the academical utterances of the philosophers. It was the voice of reason and conscience recognizing a grand abstract doctrine, but without power to solve the social problems which would arise if that doctrine should be in any measure admitted into the existing order. The Christians alone seem to carry on the doctrine as something more than a pious hope, something not more distant than any other feature of the kingdom of heaven, and easily realizable in that . The vague elements of social and political innovation in the revolt of the Donatists and the Bagaudes bear witness to the extent to which some such doctrines had been popularized. The latter had a very naïve definition of natural rights, and, on the whole, as good a one as has ever been given: "Natural rights are born with us, about which nothing is said."
By the seventh century, the churchmen had made the doctrine of natural liberty one of the tenets of the Church. Gregory the Great writes: "Since our Redeemer, Creator of all creatures, deigned to put on human form, in order by his divine grace to break the bonds of the servitude by which we were held as captives, that he might restore us to our ancient liberty, it is fitting and advantageous that those whom Nature has made free, and whom the law of nations has made subject to the yoke of servitude, should be restored, by enfranchisement, to that liberty in which they were born." This passage became authoritative for the middle ages, as well for the point of view of the doctrine, and the sanction of it, as for its substance. It is a familiar fact that
- "Digest," 1, n, 32.
- "Digest," v, 4.
- I, tit. iii, 2.
- See Jung, Sybel's "Zeitschrift," xlii, 65. He gives no authority for the definition of natural rights. Another topic which might be investigated with great advantage to social science is the history of popular revolts, with especial attention to their common elements of political and social dogma.
- Epistles, book vi, ep. 12; 77 Migne, 803.