The term "tripartite system" is commonly ascribed to French Enlightenment political philosopher Baron de Montesquieu, although he did not use such a term but 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 whose powers were not excessively centralized in a single monarch or similar ruler (a form 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. In the British constitutional system, Montesquieu discerned a separation of powers among the monarch, Parliament, and the courts of law.