On the 27th of July, 1978, Foucault held a lecture to the French Philosophical Society in Paris with the title "Qu'est-ce que la Critique? [Critique et Aufklärung]", which deals mainly with Kant's article "Answer to the question: what is Aufklärung?" of 1784. What I intend to investigate is how Foucault's reading of the Aufklärung creates a new dimension in his reading of Kant and modernity, an ethical dimension that would bring him close to some concepts articulated by Kant's critique, allowing him to situate his work within modernity, and at the same time would lead him to a broader retrospective approach to his own research. Thus, the reflection on the Enlightenment, as defined by Kant, and on modernity's critical ethos would take Foucault toward his own research, raising a perspective where it would be possible to outline what could be his philosophical project, even though understood as an open, continuously reformulated task. [ABSTRACT FROM AUTHOR]