La metaphysique du 'Dasein' dans l'oeuvre de Martin Heidegger: Repenser l'essence de la metaphysique a partir de la liberte humaine

Shortly after the publication of Being and Time in 1927, Heidegger reformulated his project of a "fundamental ontology" in terms that no longer dissimulated its metaphysical intentions. This project of a "metaphysics of Dasein" (1927-1930) presented a stunning attempt to retrieve and to lay the grounds of---and not yet to overcome---the fundamental questions of metaphysics. Inspired by Kant's and Aristotle's works, Heidegger reformulated the traditional problems---most notably those of foundation, freedom and transcendence, that were still underexposed in Being and Time---in order to make possible a new approach to the question of being, to which he had "failed" to provide a "concrete answer" in his uncompleted treatise of 1927.;First, we will discuss the Heideggerian retrieval of Aristotle's problem of the world. Considering that the tradition never succeeded in seizing the essential orientation of Aristotle's investigation on the theion , Heidegger returns to the Metaphysics in order to show that its traditional theological interpretation---that he opposes to his own theiological interpretation---dissimulated a problem not yet solved in Aristotle's thought. We will then approach this idea according to which metaphysics would be the "fundamental occurrence in Dasein ". This will lead us to uncover the hidden roots of metaphysics by revealing the origin of its questions in human freedom.;If one might think that the metaphysics of Dasein only represented an appendix to fundamental ontology or a simple relapse in metaphysics, this investigation aims to show that behind these texts is hidden an independent project that, while bridging Being and Time to the Contributions to Philosophy, constitutes a unique way in Heidegger's work to approach the essence of metaphysics. Representing the first attempt to address the problem of being after the unfolding of the fundamental ontology, the metaphysics of Dasein will reach its achievement in the exposition of an ontological concept of freedom which will give Heidegger the necessary tools to pursue---and to rethink---his path.;Key words: Martin Heidegger, Metaphysics, Dasein, freedom, foundation.;This "metaphysics of Dasein" that only lasted for three years represents, in Heidegger's work, an independent step that has not yet received all the attention it deserves. While still seeming to pursue his 1927 project of a fundamental ontology, Heidegger attempts for the first time to bring back metaphysics toward its unseen foundation Heidegger means to do so using the division of classic metaphysics in ontology and theology as a guideline. After having identified the emergence of the problem of onto-theology in the lecture courses of the mid-1920s, we will address the writings of the metaphysics of Dasein in order to show how Heidegger planned to satisfy this double structure of metaphysics.