Martin Heidegger was born September 26th, 1889 in the Black Forest region of Messkirch. He began gymnasium at Constance in 1903, but was later transferred in 1906 to Bertholds gymnasium in Freiberg. At this time he boarded at the archiepiscopal seminary of St. Georg. A mentor, Dr. Conrad Grober, gave him a copy of Brentano's "On the Manifold Meaning of Being According to Aristotle," and this early exposure to Brentano, who also influenced Husserl's phenomenology, made a great impression on Heidegger.
He took up studies to be a Jesuit by entering the Society of Jesus at Tisis, in Austria, though likely for health reasons, he was rejected as a candidate. Heidegger then decided to study for his priesthood at the Albert-Ludwig University in Freiberg, where he began lecturing and publishing papers. Here he first encounter the writings of Husserl, and was also directed by his superiors to change his studies from theology to mathematics and philosophy. Heidegger embraced the change in his direction, studying closely the work of Husserl and completing his doctorate, "The Doctrine of Judgement in Psychologism," in 1914. The following year he completed his habilitation with his dissertation, "The Doctrine of Categories and Signification in Duns Scotus." At this time he married Elfride Petri, in March, 1917, and shortly thereafter joined the German army. He thrived in the army and was promoted from private to corporal within ten months, but had to be discharged for health reasons. Shortly after the birth of his son, Jorg, in 1919, Heidegger, in a letter to a colleague, confessed that he had decided to break with "the dogmatic system of Catholicism."
Heidegger gained notoriety quickly as a phenomenologist, under the guidance of Husserl, becoming his assistant in 1919, and would later succeed him as professor of philosophy, at Freiburg. He lectured and made a colleague of Karl Jaspers, continuing a dialogue with him for many years. During this time, Heidegger's second son, Hermann, was born. By 1924, Heidegger was promoted to become an associate at the University of Marburg, where he would write his most recognized work, Being and Time (Sein und Zeit,1927; trans. 1962). He was coerced to hurry the publication of the book to retain his position at the University of Marburg.
Along with Husserl, the pre-Socratics, the Danish philosopher, S¯ren Kierkegaard, and the German philosopher, Friedrich Nietzsche, particularly influenced Heidegger. In his most important and influential work, Being and Time, Heidegger is concerned with what he considers the essential philosophical (and human) question: What is it, to be? To even ask the question, remarks Heidegger, implies that at some level the answer is already understood. As a student of Husserl, Heidegger felt that Husserl's thinking was trapped by its relationship to a concept of God and the transcendent. Heidegger shifts the mode of the subject undergoing phenomenological investigation by immersing it into its own contemplation as a being both within language (time) and within the world, hence, between a concept of being and time. Modern philosophy had forgotten the question of Being and had become concerned with the ontic, missing that which makes such an understanding of beings possible: between the "is-ness" (Being) and being as the subject of discourse or self-reflection. Heidegger argues that ontology as phenomenology must necessarily be hermeneutic, or interpretive. Truth is always both concealing and revealing. When one interpretation is opened up, other interpretations are necessarily closed off. In this sense, ontology is always provisional.
Heidegger describes the quality of Being in the concept of Dasein. The subject is thrown into a world that consists of potentially useful things, cultural and natural objects. Because these objects and artifacts come to humanity from the past and are used in the present for the sake of future goals, Heidegger posited a fundamental relation between the mode of being of objects and of humanity and the structure of time. The individual is always in danger of being submerged in the world of objects, everyday routine, and the conventional, shallow behavior of the crowd. The feeling of dread (Angst) brings the individual to a confrontation with death and the ultimate meaninglessness of life, but only in this confrontation can an authentic sense of Being and of freedom be attained. Dasein is a consciousness of the thrown quality of being between concepts that form the reality of the present, and the concern for the safety of the subject into the future. Dasein in this sense is a consciousness of consciousness. Being comes into existence at the limit of the thrown-ness of everyday existence between past and future.
After writing Being and Time, Heidegger later had a turn in his thought. This work anticipates hermeneutics (i.e., Gadamer) and post-structuralism (i.e., Foucault, Derrida, Levinas). In such works as An Introduction to Metaphysics (1953; trans. 1959), Heidegger turned to the interpretation of particular Western conceptions of Being. He felt that in contrast to the reverent ancient Greek conception of Being, modern technological society had fostered an instrumentalizing attitude that had deprived Being and human existence of meaning, a condition he called nihilism. Humanity had lost its true vocation; to recover a deeper understanding of Being that was achieved by the early Greeks and lost by subsequent philosophers.
Through his lectures at Marburg, Heidegger influenced many thinkers, including Herbert Marcuse, who would become a primary figure in Critical Theory. It was here also that he met Hannah Arendt, who later became his lover. Count Kuki Shuzo introduced Heidegger's work to Jean-Paul Sartre, who was his French tutor in Paris. Shuzo would also become the first to offer a book-length study of Heidegger, "The Philosophy of Heidegger," published in Japan. The connection of Heidegger' s thought to the East has not received much attention over the years. But it is clear that he first had his greatest impact in Japan with the writings of Count Kuki Shuzo. Further, Heidegger carried on a relationship with D.T. Suzuki, whom he met with on several occasions. He attempted to translate Lao Tzu into German, but never finished the project. Heidegger's conception of Galessenheit (releasement) is influenced by Lao Tzu, whose writings on "wu wei" (non-action) hold similarities to Heidegger's releasement-toward-things. With releasement, the human being enters meditative thinking, often characterized by a profound humility, which understands Being as a "gift" and holds itself open to the "call" of language. With Gelassenheit, Heidegger turned toward the difficult nature of the subject of language, the logos, by which beings are gathered and named. Although in naming, Being remains concealed.
In 1933, Heidegger was appointed the rector of the University of Freiburg. At this time, he also joined the National Socialist Party. One year later, Heidegger would resign as rector due to disputes with faculty and local Nazi officials. Heidegger continued his involvement with the National Socialist Party until 1945, although the degree of his involvement is still under debate. Despite the urgings of Marcuse and others, Heidegger never publicly apologized for his involvement with National Socialism. With the de-nazification hearing in 1945, Heidegger was banned from lecturing and teaching at any university by the French Military Government, and furthermore ruled that the university refuse Heidegger Emeritus status and pension him off, stripping him of his professorship. Though he continued to write and speak, he suffered a nervous breakdown in 1946. He applied for, and was granted, emeritus status, providing that he would refrain from teaching. In 1947 he published On Humanism to distinguish his phenomenology from French existentialism. By 1950, Heidegger was reinstated to his teaching position, and, one year later, he was made professor Emeritus by the Baden government. During the next decade he published a number of works including: An Introduction to Metaphysics (1953, trans. 1959), What is Called Thinking (1954, trans. 1968), What is Philosophy (1956), and On the Way to Language (1959).
During Heidegger's arrest from teaching, he found a collaborator, Medard Boss drafting, "Existential Foundations of Medicine and Psychology," which would become a seminal work in existential psychology. Heidegger hoped that Boss' application of his philosophy to psychology would help those in need of aid, as well as bring his thought to a larger audience. Throughout his career, Boss would continue to promote a Daseinanalytic approach to psychotherapy and medicine.
Heidegger's original treatment of such themes as human finitude, death, nothingness, and authenticity led many to associate him with existentialism. Indeed, his work had a crucial influence on the French existentialist Jean Paul Sartre. Heidegger, however, eventually repudiated existentialist interpretations of his work. Since the 1960s his influence has spread beyond continental Europe making an enormous impact on philosophy Western philosophy.
In 1961 Nietzsche I and II were published, in 1970 Phenomenology and Theology (Phänomenologie und Theologie) published, and in 1975 the first transcripts of Heidegger's various lectures were published, as he wished. The completed transcripts would fill more than 100 volumes, featuring all his major lectures. Heidegger died in Frieburg on May 26th, 1976.