This lecture, given by Michel Foucault at the College de France, launches an inquiry into the notion of parresia and continues his rereading of ancient philosophy. Through the study of this notion of truth-telling, of speaking out freely, Foucault re-examines Greek citizenship, showing how the courage of the truth forms the forgotten ethical basis of Athenian democracy. The figure of the philosopher king, the condemnation of writing, and Socrates' rejection of political involvement are some of the many topics of ancient philosophy revisited here.