Like a great oak tree that has colonized a grove by driving roots deep into subterranean springs not reached by lesser trees, Heidegger’s Sein und Zeit has dominated the twentieth century by feeding off traditions that lesser philosophical works cannot access. Not only a forgotten Aristotle, but also Martin Luther, Duns Scotus, medieval mysticism, and early Christianity are connected in numerous hidden ways to this massive monument to modern angst. These roots are buried deep beneath the surface of Sein und Zeit’s transcendental phenomenological discourse, but they are the source of the book’s strength. A central root runs through Heidegger’s...

Heidegger began his career at Freiburg University in 1915 as an interpreter of the Catholic Middle Ages and as, to all appearances, a devout Roman Catholic: former seminarian and son of the sexton in Meßkirch. As his views on facticity and historicity developed, he became increasingly critical of “the system of Catholicism.” He came to believe that Catholicism inured itself from life through an architectonic of Scholastic concepts, a “pseudo-philosophy” with “police power” (GA60 313). Scholasticism (not identical to Catholicism in Heidegger’s mind but nonetheless inseparable from it) distorted Aristotle and compounded the forgetfulness of being already underway in antiquity...

The early Heidegger’s circuitous path, from the Habilitationsschrift to Sein und Zeit ultimately moves in a single direction. The question that drives the Daseinanalytic of Sein und Zeit—the question of the being of time—first surfaces in Heidegger’s 1995 Scotus research. It reappears in the 1917–19 mysticism research, the remarks on Luther, the 1920–21 religion lectures, and the 1921–26 Aristotle research. The early Freiburg lectures document the variety of approaches Heidegger took to this problem, tentative solutions, experiments with language, and forays into the tradition, some that became lifelong projects, like the retrieval of non-Platonic Greek...

The influence of Scotus on Heidegger, while long a subject of general speculation, has not yet received a careful study. Heidegger’s debt to Scotus manifests itself on the opening page of Sein und Zeit. Heidegger asks about the meaning of being, that is, to what essence (logos) does the word “being” refer (SZ 2/1). He assumes a single meaning of being, a univocatio entis, which determines and makes possible all thinking and discourse. And he assumes that this notion of being is the a priori possession of Dasein; it is pre-understood in all that Dasein thinks and says. Further on,...

“The most extreme sharpness and depth of thought belong to genuine and great mysticism,” Heidegger wrote in 1955.¹ The insight came to him far earlier. Joseph Sauer’s course in the history of medieval mysticism, which Heidegger took in 1910–11, was the beginning of a lifelong interest in Meister Eckhart.² In the Habilitationsschrift, Heidegger spoke of mysticism as the other side of the Middle Ages, “the living heart of medieval Scholasticism” (GA1 205–6). The fragments published in GA60 under the erroneous title “The Philosophical Foundations of Medieval Mysticism [Outlines and Sketches for a Lecture, Not Held, 1918–1919]” actually...

The year 1917 was a turning point for Heidegger. Prior to 1917, he never openly questioned the Roman Catholic/Scholastic appropriation of philosophical methods into theology. After 1917, Heidegger began to regard Scholasticism as the site of the hegemony of theoretical speculative-aesthetic concepts in Christianity and the consequent forgetting of factical Christian life. The catalyst in this reversal was Heidegger’s discovery of Protestantism, Schleiermacher, Dilthey, and above all, Luther. We know Heidegger was reading Luther as early as 1909, although evidence of an intensive study of Luther only appears ten years later.¹ Heidegger came to believe that Luther had correctly identified...

In the light of the early Freiburg lectures, it is hard to deny Rudolf Bultmann’s claim that a direct relationship exists between the Daseinanalytic and early Christianity.¹ Heidegger and Bultmann, a specialist on the New Testament at Marburg University, worked closely together during Heidegger’s Marburg years. Heidegger participated in Bultmann’s seminars on New Testatment theology and gave lectures to Bultmann’s students. In addition to the lecture “Das Problem der Sünde bei Luther,” which Heidegger gave in Bultmann’s seminar in 1924, the lecture Der Begriff der Zeit was delivered that same year to the Marburg Theologians Society. In this short piece,...

Heidegger’s later critique of onto-theology is rooted in his earliest efforts to de-Christianize metaphysics. It is no longer disputable that he was directly inspired by Luther’s de-Hellenization of Christianity. Luther attempted to purify Christian theology of Greek metaphysics by dismantling the Aristotelian-Scholastic superstructure that had grown up over it; Heidegger undertook a complementary purification of metaphysics from Christian theology through a Destruktion of ontology down to its original Greek sources. I have argued that Heidegger’s appropriation of a Lutheran paradigm for the Destruktion of the history of ontology is not theologically neutral; on the contrary, it is theologically motivated. Heidegger’s...

Scholasticism did not leave the Jewish-Christian sense of history as it found it nor did it annul it. It sublated the early Christian understanding of time, fusing it with Hellenistic theoretical structures into a distinctively new way of being Christian. Greco-Roman “circular thinking” (the emphasis on the eternity of form) and Jewish-Christian historical thinking (the emphasis on the singularity of event), which initially tended to conflict with one another, achieved a precarious balance in Scholasticism. The Jewish-Christian historical sense was initially antagonistic to cultural and scientific life. There was no sense in building up culture when the Last Day was...