The chief object of the following pages is to indicate some of the earliest ideas of mankind, as they are reflected in Ancient Law, and to point out the relation of those ideas to modern thought. Much of the inquiry attempted could not have been prosecuted with the slightest hope of a useful result if there had not existed a body of law, like that of the Romans, bearing in its earliest portions the traces of the most remote antiquity and supplying from its later rules the staple of the civil institutions by which modern society is even now controlled. The necessity of taking the Roman law as a typical system has compelled the author to draw from it what may appear a disproportionate number of his illustrations; but it has not been his intention to write a treatise on Roman jurisprudence, and he has as much as possible avoided all discussions which might give that appearance to his work. The space allotted in the third and fourth chapter to certain philosophical theories of the Roman Jurisconsults has been appropriated to them for two reasons. In the first place, those theories appear to the author to have had a wider and more permanent influence on the thought and action of the world than is usually supposed. Secondly, they are believed to be the ultimate source of most of the views which have been prevalent, till quite recently, on the subjects treated of in this volume. It was impossible for the author to proceed far with his undertaking without stating his opinion on the origin, meaning, and value of those speculations.