Let us add another item to the long list of lessons still to be learned from Being and Time: We need an ontology of philosophical failure. What is failure in philosophy? I am not asking about failing at philosophy either by failing to do it or by doing it badly. I mean the more deeply puzzling phenomenon of doing philosophy as well as it has ever been done and yet failing in that philosophy, nonetheless. What does it mean to say, rightly, that Being and Time fails, or that it is (in Kisiel’s words) “a failed project”? In what way can and should the most influential philosophical work of the twentieth century be considered a failure, judged by the most sympathetic standards of an “internal” or immanent reading (that is, by its own lights or on its own terms) rather than by some measure “external” to the text itself? What did Being and Time set out to accomplish, and why did it fail to achieve that goal? Is this a failure Heidegger could have avoided or rectified if he had had time to complete the book in the way he originally planned? Or is this a necessary failure, one that follows from some inexhaustibility inherent in the subject matter of Being and Time itself, and so from the impossibly ambitious nature of its attempt to answer “the question of being”? In what way must philosophy fail itself (to employ a polysemic locution), necessarily falling short of its own deepest, perennial ambitions? What is the lesson of such necessary philosophical failure?

Chapter 1 argues that Heidegger, like many reconstructive interpreters, takes up the main question posed by the first Critique and attempts to identify Kant’s most plausible line of response to it, consulting the claims in Kant’s text alongside Heidegger’s own beliefs. Because Heidegger seeks to attribute true claims to Kant, his method of interpretation resembles that of Davidson and Gadamer. However, Heidegger improves on their method, because he recognizes the methodological role of disagreement in coming to agree with some author, thereby making room for differences in view between interpreter and text. He argues that we should expect great thinkers to struggle with their subject matter, offering competing strands of argument as they attempt to work out their view. The interpreter, therefore, must isolate the most promising strand of argument, differentiating it from less compelling arguments. Accordingly, Heidegger offers a two-strand interpretation of Kant that differentiates an insightful line of argumentation prioritizing imagination from a less promising line prioritizing understanding. Further, Heidegger offers a theory of error explaining why Kant struggles with his subject matter: Kant retreats to his less compelling argument due to the anxiety he experiences in uncovering the fundamental structure of the human being.

The Introduction provides a basic account of Heidegger’s method of interpreting Kant, and the major philosophical themes that feature in his interpretation. These themes include fundamental ontology, human finitude, receptivity, and time. The Introduction also introduces the main sources under consideration: Heidegger’s 1927–1928 lecture series on Kant, and his 1929 Kant book. Finally, an overview of the chapters in the book is provided.