Such a centralization of the national institutions was quite necessary if the danger of being dominated by France was to be avoided. France was rapidly becoming united under the leadership of its kings, who possessed a permanent army, the right to impose a perpetual _taille_, and the exercise of sovereign justice. In the face of this united and powerful monarchy, the Burgundian state could not remain separated. The Belgian provinces could no longer remain isolated from each other and limit themselves to an individualistic and egotistic policy. It was seen that everything ought to be concentrated in the hands of a strong prince. That was the new idea that was introduced into the constitution of the Belgian principalities, an idea that had never appeared prior to the fifteenth century. Throughout the Middle Ages the antiquated idea of the state as a collective person distinct from its members never clearly appears. The concept of sovereignty--absolute power subject to no control--was also lacking. The individual life dominated the life of the community. Little by little the renascence of the study of Roman law introduced other concepts, namely, those of state and sovereignty. The students of Roman law, the “legists,” stood for a government that would be one, indivisible, strong, absolute, and active. They believed that all that tended to limit the complete exercise of public authority should be discarded: the state was held to be impersonal and almighty. That new concept of the state was embodied in the politics of the Burgundian dukes during the fifteenth century. Centralization and the absolute power of the prince took the place of the former personal and collective privileges. This idea triumphed, not only because the Burgundian dukes were strong, but also because it was in accordance with the needs of the time and the wishes of the majority of the people. Of course, the dukes, when they tried to realize their political centralization, met with some resistance on the part of the powerful communes. But Philip the Good cleverly avoided any open fight. He simply tried to subject the cities to his control--to prevent them from being a state within the state. He took part in the appointment of the magistrates, ordered their accounts to be examined by his officers, forbade advantage to be taken of the small cities and the peasantry, and made the judgments of their tribunals subject to review by his own councils of justice. Flanders endeavored to evade the results of that policy. There were serious revolts in Bruges (1436-47) and in Ghent (1450-53), and the cities of Brabant, particularly Malines, seemed unwilling to adapt themselves to the new situation.