The following conditions may, I think, be historically traced to the nation capable of a polity, which suggests principles for discussion, and so leads to progress. First, the nation must possess the PATRIA POTESTAS in some form so marked as to give family life distinctness and precision, and to make a home education and a home discipline probable and possible. While descent is traced only through the mother, and while the family is therefore a vague entity, no progress to a high polity is possible. Secondly, that polity would seem to have been created very gradually; by the aggregation of families into clans or GENTES, and of clans into nations, and then again by the widening of nations, so as to include circumjacent outsiders, as well as the first compact and sacred group--the number of parties to a discussion was at first augmented very slowly. Thirdly, the number of 'open' subjects--as we should say nowadays--that is, of subjects on which public opinion was optional, and on which discussion was admitted, was at first very small. Custom ruled everything originally, and the area of free argument was enlarged but very slowly. If I am at all right, that area could only be enlarged thus slowly, for Custom was in early days the cement of society, and if you suddenly questioned such custom you would destroy society. But though the existence, of these conditions may be traced historically, and though the reason of them may be explained philosophically, they do not completely solve the question why some nations have the polity and some not; on the contrary, they plainly leave a large 'residual phenomenon' unexplained and unknown. II. In this manner politics or discussion broke up the old bonds of custom which were now strangling mankind, though they had once aided and helped it. But this is only one of the many gifts which those polities have conferred, are conferring, and will confer on mankind. I am not going to write an eulogium on liberty, but I wish to set down three points which have not been sufficiently noticed.