In the lecture of December 16, 1980, Deleuze proposes a cross-reading of Spinoza and Rousseau. First, Deleuze reinterprets Rousseau’s morality in the light of Spinoza’s critique of ‘morality’ based on the opposition of good and evil; second, and reciprocally, he rereads Spinoza’s practical and ethical philosophy from a concept extracted from Rousseau’s work: that of the ‘materialism of the wise’. According to Deleuze, this ‘practical materialism’ evoked by Rousseau, consisting of both ‘determinism’ and ‘sensualism’, has a Spinozist inspiration, insofar as (...) it has an amoralist dimension, close to the critique of morality developed in the Ethics. But on the other hand, Rousseau’s ‘materialism of the wise’ allows us, conversely, to reread the Spinozist explanation of the conquest of freedom, by revealing the presence of practical principles very close to those of Rousseau’s ethical materialism. The cross-reading of Spinoza and Rousseau thus presents a double aim: on the one hand, to identify the presence of amoralist themes and issues in Rousseau’s work; on the other, to reveal the existence of materialist principles in the Spinozist ethical itinerary. (shrink)