It is fairly straightforward to trace the philosophical influences on Discourse on Inequality. Before writing the Discourse on Inequality, Rousseau worked as a secretary to a French tax-collector called Dupin. He was required to read and summarize a variety of works, including Montesquieu's Spirit of the Laws. Montesquieu's huge work develops a pessimistic view of the nature of modern man, arguing that modernity is a corrupt and decayed state, in which the glory of the classical period is no longer possible. Rousseau's notion of uncovering man's true nature, and dissecting modern government owes much to Montesquieu, although he disagrees absolutely with Montesquieu's conclusions.

Rousseau also read deeply in classical and modern philosophy and literature, such as Plutarch, Grotius, Hobbes, and Pufendorf. The footnotes to Discourse on Inequality show the depth of this reading. Here, Rousseau cites not only philosophical works but also anthropology and travel writing. Accounts by seventeenth and eighteenth century travelers of savage tribes and human-like primates are fuel for Rousseau's arguments about human nature, because they demonstrate how man in the state of nature might have behaved. He engages in debate with contemporary writers on human nature and natural history, such as Buffon and Condillac.

Several other philosophical contexts are important to understand. A vital part of Discourse on Inequality is Rousseau's reaction to natural law theory, particularly that of Hobbes and Grotius. Natural law theory is an attempt, dating back to the classical period, to identify a series of principles set out either by God or by reason, on which all men can agree for their self-preservation. The question Rousseau has to answer in Discourse on Inequality is whether inequality is authorized by natural law, but it soon becomes obvious that he redefines this particular term to suit his argument.

Equally important is the contemporary debate about human nature and forms of government. Philosophers such as Montesquieu considered the possibility of recreating the great achievements of classical Greece and Rome, and particularly of recreating classical systems of government. Montesquieu argued that human nature is corrupt, and that republican government is possible only with great effort and self-control; therefore monarchy, the most common form of government in Europe at the time, is also the best for the modern world. Human nature was seen to limit what could be achieved politically. By tackling questions about human nature and the foundations of modern inequality, Rousseau engages with this debate to a great extent. Also important here was the European political situation, in which the great monarchies such as that of France were dominant, and republics such as Geneva were rare; for the background to Rousseau's dedication of Discourse on Inequality to Geneva, see the chapter by chapter summary.