Rousseau's The Social Contract is a cornerstone in modern political and social thought and makes a strong case for democratic government and social empowerment. The Social Contract argued against the idea that monarchs were divinely empowered to legislate. Rousseau asserts that only the general will of the people has the right to legislate, for only under the general will can the people be said to obey only themselves and hence be free. Discourse on the Arts and Sciences commonly known as The First Discourse, is an essay by philosopher Jean-Jacques Rousseau which argued that the arts and sciences corrupt human morality. This work is considered one of his most important works. In Discourse on the Origin of Inequality, Rousseau first exposes in this work his conception of a human state of nature and of human perfectibility, an early idea of progress. He then explains the way in which, in his view, people may have established civil society, and this leads him to conclude that private property is the original source and basis of all inequality. In Discourse on Political Economy Rousseau explains his own philosophical and political conception of republicanism.