There was one advantage incidental to the feudal law of primogeniture, which did not belong to the Irish law of succession before or after the institution of tanistry. In feudal law, the lawful successor might be a child, an invalid, a demented person, and in some countries a woman. In feudal law, as in Irish law, and in ancient law generally, the ruler was also chief judge and chief military commander for his people and territory. Each of Henry's feudal grantees in Ireland held and exercised these functions. The kings of England themselves, from William the Conqueror to Henry II. and the Saxon and Danish kings before them, were judges and generals as well as chiefs of State. The Irish law contemplated a ruler who was fitted in mind and body to exercise these functions. The law of primogeniture often failed to secure such fitness. At first sight, the Irish law seems to have the advantage, but on closer consideration the case will appear otherwise. If the ruler of the state combines in his own person the offices of judge and military commander and performs these offices in person, as well as the presidency of the public assembly, it follows that there must be as many states and rulers as there are presidents of assembly, judges of law, military commanders. And this is what we actually find in ancient Ireland. Most of the modern baronies, so-called, take the place of ancient kingdoms. The ruler being in the people's mind fit to judge in litigation and to lead in war and to preside over the assembly, and being unfit to rule as king when he could not perform these functions, there was no place in so simple a polity for ministers of State, and there was no regular delegation of these important duties. I think it will be admitted that the development of ministerial offices is one of the greatest phases in political progress. On the other hand, the feudal law of primogeniture, under which the ruler at times might be a child, an idiot, or a weakling, rendered ministers of State a necessity. When Norman feudalism came to Ireland, it was just emerging from a condition similar to what it found in Ireland, and so the domestic polity of Ireland called for no remark from Giraldus, who was ready to find fault with anything, even with the fact that the Irish reared their children in a natural way, and succeeded admirably with it, instead of shaping their limbs and bodies with swathings and bandages. In southern Italy, the Normans found the civil service of the Byzantine emperors in operation; adopted it, and from them it spread to Normandy and England. This transformation was just taking place at the time of their invasion of Ireland, and was providing them with an apparatus of statecraft which the Irish did not possess.