Ahmad Rajabi's Lectures: An Introduction to Heidegger's Later Philosophy, a Commentary on Identity and Difference

A commentary by Rajabi on *Identity and Difference*, an introduction to Heidegger's later philosophy, emphasizing the possibility of rationality and truth. The later Heidegger is concerned with free rational responsibility, and his critique of metaphysics arises from the crisis of the foundational view between reason and Being.

In these lectures, an attempt has been made, through the exposition and interpretation of two important and well-known writings, “The Principle of Identity” and “The Onto-theo-logical Constitution of Metaphysics” from the treatise Identity and Difference, to provide an introduction to the framework of Heidegger’s later thought after the turn. The main emphasis in the course of interpreting these two texts is on the question of the possibility of rationality and truth in philosophy, in the sense that, contrary to the prevailing view, the later Heidegger is precisely concerned with rationality and the free rational responsibility of the human being in belonging to the binding horizon of truth. The fundamental critique he levels at metaphysics arises from a crisis toward which the historical course of metaphysics, through the foundational view of the relation between reason and Being, has advanced up to Hegel and finally Nietzsche, and which is nothing other than the subsumption of Being under self-thinking reason and its transformation into the will to power, and the rendering meaningless of the horizon of appearance, Being, and truth, and thus, the meaninglessness of reason and rationality, as well as the continuation of that crisis up to the present in the domineering view of the world and the human being.

Heidegger’s later thought and its fundamental concepts, such as event, concealment, groundlessness, the history and destiny of Being, and the like, are expounded and interpreted in light of this fundamental question: in what sense, for the possibility of rationality and truth, must reason’s openness to Being as the horizon of truth be redesigned based on the acknowledgment and recognition of the prior realm of the act of appearing in its absolute precedence and, in this respect, its inaccessibility, and how Heidegger’s thinking is entirely directed toward uncovering and demonstrating such a necessity as the fundamental criterion of phenomenology.

The interpretation of the two aforementioned texts provides the opportunity for the structure of Heidegger’s later thought, regardless of his usual semi-poetic and allusive mode of expression in the final years of his intellectual life, to draw attention to his precise method of analysis and deconstruction regarding the ultimate foundations of rationality, that is, the analysis of the principle of identity as the starting point of rational self-evidence, as well as the ontological principle of difference between beings and Being.

These lectures were presented in the form of a course on the Interpretation of Philosophical Texts in the Master’s program of Philosophy at the University of Tehran in the second semester of 1400-1401 by Ahmad Rajabi (Assistant Professor in the Department of Philosophy, University of Tehran).