who said legitimate power is often called authority
Authority Max Weber, in his sociological and philosophical work, identified and distinguished three types of legitimate domination (Herrschaft in German, which generally means 'domination' or 'rule'), that have sometimes been rendered in English translation as types of authority, because domination isn't seen as a political concept in the first place.[citation needed] Weber defined domination (authority) as the chance of commands being obeyed by a specifiable group of people. Legitimate authority is that which is recognized as legitimate and justified by both the ruler and the ruled.
Separation of powers The term tripartite system is commonly ascribed to French Enlightenment political philosopher Baron de Montesquieu, although he did not use such a term. In reality he referred to "distribution" of powers. In The Spirit of the Laws (1748), Montesquieu described the various forms of distribution of political power among a legislature, an executive, and a judiciary. Montesquieu's approach was to present and defend a form of government which was not excessively centralized in all its powers to a single monarch or similar ruler, form of government known then as "aristocracy". He based this model on the Constitution of the Roman Republic and the British constitutional system. Montesquieu took the view that the Roman Republic had powers separated so that no one could usurp complete power.[8][9][10] In the British constitutional system, Montesquieu discerned a separation of powers among the monarch, Parliament, and the courts of law.