The Era of the Individual, widely hailed as Renaut's magnum opus, the author explores the most salient feature of post-structuralism: the elimination of the human subject. At the root of this thinking lies the belief that humans cannot know or control their basic natures, a premise that led to Heidegger's distrust of an individualistic, capitalist modern society and that allied him briefly with Hitler's National Socialist Party.

While acknowledging some of Heidegger's misgivings toward modernity as legitimate, Renaut argues that it is nevertheless wrong to equate modernity with the triumph of individualism. Here he distinguishes between individualism and subjectivity and, by offering a history of the two, powerfully redirects the course of current thinking away from potentially dangerous, reductionist views of humanity.

Renaut argues that modern philosophy contains within itself two opposed ways of conceiving the human person. The first, which has its roots in Descartes and Kant, views human beings as subjects capable of arriving at universal moral judgments. The second, stemming from Leibniz, Hegel, and Nietzsche, presents human beings as independent individuals sharing nothing with others.

In a careful recounting of this philosophical tradition, Renaut shows the resonances of these traditions in more recent philosophers such as Heidegger and in the social anthropology of Louis Dumont.