It is proposed here to show upon what principles and by what rules Greek and Roman society was governed. We unite in the same study both the Greeks and the Romans, because these two peoples, who were two branches of a single race, and who spoke two idioms of a single language, also had the same institutions and the same principles of government, and passed through a series of similar revolutions. We shall attempt to set in a clear light the radical and essential differences which at all times distinguished these ancient peoples from modern societies. In our system of education, we live from infancy in the midst of the Greeks and Romans, and become accustomed continually to compare them with ourselves, to judge of their history by our own, and to explain our revolutions by theirs. What we have received from them leads us to believe that we resemble them. We have some difficulty in considering them as foreign nations; it is almost always ourselves that we see in them. Hence spring many errors. We rarely fail to deceive ourselves regarding these ancient nations when we see them through the opinions and facts of our own time.