Translated by Pete Ferreira
Therefore, there is a, not merely exoteric, connection linking together Heidegger's confrontations with the tradition, and with the three principals specifically, with Husserl, with Aristotle and with Kant. As to their ordering, one can say that Heidegger mainly confronts Husserlian phenomenology and later arrives at his interpretation of Aristotle starting with the questions that were left unanswered in the confrontation with Husserl. In the thought of the latter, in fact, he had come to see, accomplished and brought to its logical conclusions, the founding of a philosophy of the subject directed primarily towards scientific understanding and logico-theoretical categories. Turning to Aristotle, instead, he believes we can discern a complete repertoire of fundamental ontological determinations of human life, and most importantly without the assumptions of modern philosophies of the subject. with Kant, finally, Heidegger strains to see an overcoming of the traditional forgetfulness of the connection between being and time, from the fact that Kant had attempted to think the unity of the fundamental determinations of human life, as identified by Aristotle, but in a rhapsodic approximation, without addressing the theme of their unity; and, even unknowingly, Kant would determine this unity as temporality, which led him to link temporality and subjectivity, and reach that foundation of finitude that – like the Heideggerian equation to being-there and originary temporality – allows reposing the problem of being and of time.
Coming now to the interpretation of Aristotle, the gap compared to the previous confrontations is immediately apparent, those conducted in his early years following the reading of Brentano and Braig, be it for the wider themes, as for the more mature and deeper speculative commitment, and also for the higher interpretative level it reaches. Notwithstanding the centrality and importance of the problem of being, a certain thematic shift is also evident. Since, although being remains the general horizon and the ultimate goal of the research, Heidegger now develops the confrontation with Aristotle along the themes that will later be more central in Being and Time; they are at least three: the problem of truth, the problem of the 'subject', and the problem of temporality.
To understand this thematic shift and the qualitative leap that accompanies it, it is helpful to consider that the years between the doctoral thesis and the call to Marburg, namely his first period teaching at Freiburg, are for Heidegger a time of reflections, crises and radical changes. There is a significant document, that is worth citing extensively, in which one can grasp the profound transformation in Heidegger in those years. This is a letter dated January 9, 1919, addressed to Engelbert Krebs1. Here's the text:
1 This letter is preserved in the Nachlaß of Engelbert Krebs at the Seminar of Dogmatic Theology at the University of Freiburg, and was published by B. Casper in Martin Heidegger und die Theologische Fakultät (1909-1923), «Freiburger Diözesan-Archiv», 32, 1980, pp. 534-541, in particular p. 541. On the task of Heidegger in these years see Thomas Sheehan, "Heidegger's Early Years: Fragments for a Philosophical Biography", in Heidegger. The Man and the Thinker, Precedent Publishing, Chicago, 1981, pages 3-19; on the relationship with Husserl see K. Schuhmann, Husserl-Chronik. Denk-und Lebensweg Edmund Husserls (Husserliana Dokumente, 1), Nijhoff, Den Haag 1977.