If philosophy poses the question "what is truth?", there is something before philosophy that constitutes its prerequisite: the ability to question what is presented as truth, to deny it, to oppose it; the readiness to stand against authority, that is, spiritual and political power, and to dare to critique it - the "critical ethos" or critical stance.

Foucault dedicated the last years of his life to studying the history of the critical ethos in Western civilization and, more specifically, to a rather neglected concept of ancient Greek thought: the concept of parrhesia. In the lectures translated here, which he delivered at the University of Berkeley in the fall of 1983, Foucault examines the genesis, forms, and evolution of parrhesia from the 5th century BC to late antiquity.

In Euripides' Ion, we initially observe the questioning of the gods as the source of truth; the oracle ceases to be the seat of truth and becomes the city itself. In Euripides' Orestes, we see parrhesia as a right within the democratic city, and the problems it creates within the public competition for truth. With Socrates and Plato, the problem of truth shifts from the public space to the soul: How does the life you live reconcile with the truth you claim to uphold? Among the Cynics, parrhesia takes the form of public questioning of common values, while among the Stoics, criticism turns inwards, manifesting as a continuous self-examination of the individual in their struggle for inner, thus true, freedom.