If we should try to set down the valuable contributions which the Romans have made to modern political theory, or the achievements of the Romans which we may study with profit, or the political qualities in them which we may imitate to advantage, or the important political principles or institutions which we have inherited from them, we should think of the doctrines of popular sovereignty, of the equality and brotherhood of man, of the practical proof which they have given us of the value of a flexible constitution, of their teachings concerning the theory of the state, and of their introduction of the historical method of studying political institutions. Of all these contributions to modern civilization we have already spoken. We should also think of their devotion to the state, of their regard for law and tradition, of their wise opportunism which made their political thinking practical and concrete, of their development of a marvellous body of civil law, of their careful observance of the principle of local self-government, with its acceptance of local institutions and practices, and of their success in promoting law and order and a feeling of social solidarity, in improving material conditions throughout the world, and in governing and civilizing backward peoples. This is a long list, but in all these respects the political acumen of the Romans was noteworthy, and their achievements either lie at the basis of modern civilization, as we shall see, or may furnish us guidance in our political development. In our discussion of the different branches of the government, and of various fields of political activity, we shall have occasion to take up in detail many of these points which have not yet been mentioned. 4. THE LEGISLATIVE AND EXECUTIVE BRANCHES OF GOVERNMENT _i._ RESEMBLANCES BETWEEN ANCIENT AND MODERN