We have seen that difficulties could arise in the various systems of ecclesiology and political theory built around the Roman law doctrine, ‘The ruler is greater than individuals but not greater than the whole people.’ Developed in one way the formula could lead on to an awkward theory of ‘double sovereignty’ in which both ruler and people had the right to make law. In its more typical forms the doctrine tended to a simple republicanism even if, by courtesy, the supreme magistrate was styled ‘emperor’ or ‘king’ or even ‘pope’. That is to say, the assembled representatives of the people or a majority of them always prevailed over the ruler who, in the last resort, was conceived of merely as their proctor or agent. And this did not correspond to the facts of life in church or state in most parts of Europe. Moreover, although the constitutional theorists we have considered so far often worried about possible tyranny in a king or pope, it never seems to have occurred to them that a representative assembly might also abuse its powers.

An alternative theory of government grew up in the seventeenth century, influenced in part by English political experience and especially by the crisis of the Civil War, when many people came to realize for the first time that a parliament could be just as oppressive as a king. In this alternative theory tyranny was avoided by a diffusion of authority within a complex central government. The government was composed of several members – in England, king, lords, and commons, in later versions various institutionalized forms of executive, judiciary, and legislative power.