"Montesquieu's most influential work divided French society into three classes: the monarchy, the aristocracy, and the commons. Montesquieu saw two types of governmental power existing: the soverign and the administrative. The administrative powers were the executive, the legislative, and the jucidial. These should be separate from and dependent upon each other so that the influence of any one power would not be able to exceed that of the other two, either singly or in combination. This was a radical idea because it completely eliminated the three Estates structure of the French Monarchy: the clergy, the aristocracy, and the people at large represented by the Estates-General, thereby erasing the last vestige of a feudalistic structure.Likewise, there were three main forms of government, each supported by a social "principle": monarchies (free governments headed by a hereditary figure, e.g. king, queen, emperor), which rely on the principle of honor; republics (free governments headed by popularly elected leaders), which rely on the principle of virtue; and despotisms (enslaved governments headed by dictators), which rely on fear. The free governments are dependent on fragile constitutional arrangements. Montesquieu devotes four chapters of The Spirit of the Laws to a discussion of England, a contemporary free government, where liberty was sustained by a balance of powers. Montesquieu worried that in France the intermediate powers (i.e., the nobility) which moderated the power of the prince were being eroded. These ideas of the control of power were often used in the thinking of Maximilien de Robespierre."
I hate you for beating me to this subtle beauty