book of the "Politics" He says that some held that slavery was against nature. Such persons, whoever they were, must have derived their opinions entirely from humane impulse and poetic enthusiasm. Aristotle was not of that tone of mind. He could not find in history any example of a state which had not slavery. When he examined the state in which he lived he easily saw that slavery was of its very essence. He therefore held that slavery was a natural necessity. Such it was in the sense that it was rooted in the nature of the classical state. It is undeniable that the classical state could not have grown up and could not have produced its form of civilization without slavery. It must also be recognized as a fact that no other organization of society has yet shown itself capable of that degree of expansion which the Roman state developed by means of slavery. The mediæval state broke down under the first expansive requirement which was made upon it. Whether the modern state, based on natural agents and machinery, is capable of expansion or not, is yet to be proved. There seems to be ample reason to believe that it is, unless the modern world votes not to go on; but, if the modern world votes to go on and not be afraid, it can only do so by virtue of education, and then it is subject to the remonstrance of Mr. Karoly at the head of this article, and of others who think like him. To return to the classical state: it remains only to observe that slavery was likewise the fate of that state which, having enabled it to grow up to immense power and achievement, also inevitably carried it down to ruin and disgrace. It is free to us all to speculate on the question whether every force which makes high expansion possible will not also bring with it its own form of inevitable destruction or decay. Aristotle, therefore, proceeding upon the historical method and upon observation, found that slavery was necessary and expedient within the limits of the age and the form of society he was discussing.
Fuller expression of the dogma of natural liberty comes only with the Christian era. Dio Chrysostom, at the end of the first century, expresses himself in favor of it, but his declaration is incidental and can be taken only as rhetorical.[1] It is among the Christian writers that it first finds distinct and enthusiastic expression. With them it is rather an inference from fundamental doctrines of the faith than an actual article of the creed, although they quote texts freely in support of it. The doctrines of Christianity are undoubtedly favorable to it, and the inference was direct and easy. Tertullian (fl. c. 200 a. d.), addressing heathen, declares, "We are your brothers by the right of one mother—Nature."[2]
It was not confined to Christians, however. It is very probable
