This volume presents the first critical edition of this crucial lecture alongside a previously unpublished lecture about the culture of the self and three public debates with Foucault at the University of California, Berkeley, in April 1983. There, for the first time, Foucault establishes a direct connection between his reflections on the Enlightenment and his analyses of Greco-Roman antiquity. However, far from suggesting a return to the ancient culture of the self, Foucault invites his audience to build a "new ethics" that bypasses the traditional references to religion, law, and science.