Martin Heidegger (1889-1976) was an influential and controversial German philosopher, primarily concerned with Being, and phenomenology---who was widely (perhaps incorrectly) also perceived as an Existentialist. His relationship with the Nazi party in Germany has been the subject of widespread controversy and debate [e.g., Heidegger and Nazism,Heidegger and the Nazis,Heidegger's Crisis: Philosophy and Politics in Nazi Germany,Heidegger and the Question of National Socialism, etc.] He wrote many other books, such as Being and Time,Introduction to Metaphysics,Basic Writings,Nietzsche, Vol. 1: The Will to Power as Art, Vol. 2: The Eternal Recurrence of the Same,Nietzsche: Vol. 3: The Will to Power as Knowledge and as Metaphysics; Vol. 4: Nihilism,The Question Concerning Technology, etc.

Heidegger wrote in the Preface to the Third Edition (1949) of this book [originally published as part of a Festschrift to Husserl], “The treatise ‘The Essence of Reasons’ was written in 1928, at the same time as the lecture ‘What is Metaphysics?’ The latter considers the problem of Nothingness, while the former defines the Ontological Difference. Nothingness is the Not of being and thus is Being experienced from the point of view of being. The Ontological Difference is the Not between being and Being. Yet Being, as the Not to being, is no more a nothingness in the sense of a ‘nihil negativum’ than the Difference, as the Not between being and Being, is merely a distinction of the intellect… Why shouldn’t considerate minds finally begin to look thoughtfully into this matter, which has been awaiting their attention for two decades?” (Pg. 3)

He begins the essay by acknowledging, “it is doubtful whether one can get at the essence of reasons by characterizing what is ‘common’ to the various ‘kinds’ of reasons, even though doing so might undeniably bring one closer to a preliminary clarification of reasons.” (Pg. 5-7)

He states, “The proper function of representing is to OBJECTIVIZE being---which itself must then always be already manifest. Ontical manifesting, however, takes place in our situating ourselves in the midst of being, through our moods and drives, as well as in the conative and volitional kinds of behavior toward being that are grounded in the way we find ourselves situated.” (Pg. 21)

He notes, “The Gospel of John uses the concept of ‘kosmos’ with uncommon frequency---particularly in contrast with the Synoptic Gospels---and at the same time in a very central sense. ‘World’ stands for the basic form of human Dasein as estranged from God or, more simply, the character of the Being of man. ‘World’ is also, then, a regional term for the whole of mankind, without distinction of wise men and fools, righteous men and sinner, Jews and Gentiles. The central meaning of this wholly anthropological concept of world is expressed in its function as an opposing concept of the divine filiation of Jesus, which is itself conceived as life, truth, and light.” (Pg. 53)

He observes, “Conceptually, the disclosed world may be either partially or completely opaque; it may even be interpreted as one being among others; we may not know anything explicit about the transcending of Dasein; the freedom of Dasein, and so the project of the world, may hardly be awake. And yet it is only AS Being-in-the-world that Dasein is preoccupied with being. Dasein grounds (establishes) world only insofar as it grounds itself in the midst of being.” (Pg. 109-111)

He points out, “the Why arises of transcendental necessity… Its basic forms are: ‘Why thus and not otherwise?’, ‘Why this and not that?’, ‘Why anything at all and not nothing?’ A preconceptual, prior understanding of what something is, of how it is, and even of Being (Nothing) lies implicit in the Why, no matter how it is expressed. This understanding of Being makes the Why possible in the first place. That is, it contains the ultimate and primordial answer to every question. As the most primary answer, the understanding of Being lays the ultimate FOUNDATION for all inquiry. In it, transcendence is FOUNDING. And since Being and its constitution are disclosed in transcendence, transcendental founding is called ONTOLOGICAL truth.” (Pg. 115-117)

He summarizes, “looking back to our point of departure, we should briefly discuss whether we have made any progress… with the problem of the ‘principle of sufficient reason’ by illuminating the ‘essence’ of reasons. The principle says that every being has its grounds or reason. The foregoing remarks clarify, in an introductory way, WHY this is so. Since, from the beginning, Being… FOUNDS primordially, every being announces its ‘reasons,’ whether or not they are grasped explicitly and are properly defined. Because ‘reasons’ are a transcendental, essential character of Being, the principle of sufficient reason is valid for every BEING, because ‘there is’ Being (not being) only in transcendence as world-projecting and situated grounding. Thus we see that the ‘birthplace’ of the principle of sufficient reason lies… in transcendence itself. Freedom is the origin of the principle of sufficient reason, for founding, expressing itself as ontological truth, is grounded in freedom, the unity of outstripping and deprivation.” (Pg. 121-123)

This brief book (printed with the German text facing the English translation) will be of great interest to those studying Heidegger---particularly his early philosophy.