Rousseau's Discourse on Inequality is one of the most powerful critiques of modernity ever written. It attempts to trace the psychological and political effects of modern society on human nature, and to show how these effects were produced. In order to do this, Rousseau demonstrates that human evolution and the development of inequality between men are closely related. The result is both a sweeping explanation of how modern man was created, and a sharp criticism of unequal modern political institutions. In the Discourse, Rousseau diagnoses the problem with modern political institutions that he later attempted to resolve in the Social Contract.
The Discourse was originally written as an entry for an essay competition run by the Dijon academy of Arts and Sciences in 1754. The essay question was "What is the origin of inequality among men, and is it authorized by the natural law?" Rousseau had won the competition in 1750 with his First Discourse (on the Arts and Sciences). He failed to win a prize with this second discourse, but its publication brought him widespread praise, and an important place in history of philosophy.
The Discourse on Inequality is a powerful, passionate argument, which is dazzlingly written and broad in scope. Its methodology is brilliant and daring. Rousseau attempts to trace man back to his natural state, discarding the authority of the biblical account. At heart, though, the Discourse is a daring guess, an exercise in conjecture and reconstruction. Although the Discourse is closely related to eighteenth-century debates about the nature of man, and about different forms of government, it also has a wider significance. It is important because Rousseau asks questions about who we are and what we want—questions that still apply today. Rousseau's central idea, that modern people exist within an ever-increasing system of needs in which the opinion of others is vitally important, is hugely influential. Traces of it can be found in Hegel's idea of civil society, and in Marx's description of the alienated worker. More importantly, it is evident in our lives. When you look in the mirror to check your appearance, or wonder about how popular you are, or what your friends think of you, you are taking part in a process described perfectly by Rousseau. The idea that modern life is imperfect and unequal was not an idea invented by Rousseau, but he presents a fascinating argument for how inequality came to manifest itself. Almost every major philosopher in the eighteenth century, as well as many thousands of ordinary people, read the Discourse. Anyone who wants to understand the eighteenth, or indeed the twentieth, century, should read it too.