Martin Heidegger

Martin Heidegger (26 September 1889 – 26 May 1976) was a German thinker whose ideas helped shape phenomenology, hermeneutics, and existentialism. His influence spread across later philosophy, the social sciences and humanities, and theology.

His major work, *Being and Time* (1927), is often ranked among the most important works of modern philosophy. In it, he introduced the idea of *Dasein* ("being-there") to capture what is distinctive about human existence. He argued that people have a "pre-ontological" grasp of being that guides how they live and act, which he explored through the unified structure of "being-in-the-world." By analyzing Dasein, Heidegger aimed to revive what he called "the question of being"—the fundamental inquiry into what makes anything intelligible as the thing it is. This question, he believed, had been ignored or buried throughout Western philosophy since the ancient Greeks.

In his later work, Heidegger focused more on technology, language, art, and poetry. He developed ideas about human "dwelling" in the world and criticized what he saw as the nihilistic direction of modern technological civilization. Thinkers such as Jean-Paul Sartre, Hans-Georg Gadamer, Hannah Arendt, Jacques Derrida, Emmanuel Levinas, and Richard Rorty were all deeply shaped by engaging with his thought, whether they agreed or opposed him.

Heidegger’s legacy is complicated and darkened by his involvement with Nazism. In April 1933, he was elected rector of the University of Freiburg and joined the Nazi Party, remaining a member until 1945. How committed he was to Nazism, and whether his philosophy is tied to his political choices, remain matters of intense scholarly debate. After the war, denazification proceedings banned him from teaching; this ban was lifted in 1949, after which he returned to lecturing at Freiburg. During his enforced withdrawal, he still influenced others through private seminars and meetings at his home. His refusal to publicly renounce his Nazi ties or express clear remorse has continued to trouble those who study his work.

**Biography**

**Early life and education**

Heidegger was born on 26 September 1889 in rural Meßkirch, Baden, to Johanna and Friedrich Heidegger. His father was the sexton of the village church, and Martin was raised Catholic.

In 1903, he began training for the priesthood. He entered a Jesuit seminary in 1909 but was discharged within weeks due to heart trouble. Around this time, he first encountered the work of Franz Brentano, which is credited with sparking his interest in the question of Being—specifically Brentano’s thesis *On the Manifold Sense of Being according to Aristotle*. He then studied theology and scholastic philosophy at the University of Freiburg.

In 1911, he broke off his priestly training and turned to recent philosophy, especially Edmund Husserl’s *Logical Investigations*. He graduated in 1914 with a thesis on psychologism, *The Doctrine of Judgment in Psychologism: A Critical-theoretical Contribution to Logic*. The next year, he completed his habilitation thesis on Duns Scotus, supervised by neo-Kantian Heinrich Rickert and influenced by Husserl’s phenomenology. Its English title is *Duns Scotus's Doctrine of Categories and Meaning*.

He tried to get the Catholic philosophy post at Freiburg on 23 June 1916 but failed despite support. He then worked as an unpaid *Privatdozent* and served as a soldier during the last year of World War I. His service lasted ten months, mostly in a meteorological unit on the western front, after being deemed unfit for combat.

**Professorship**

From 1919 to 1923, Heidegger taught at the University of Freiburg and became an assistant to Edmund Husserl, who had been a professor there since 1916.

**Marburg**

In 1923, Heidegger was elected to an extraordinary professorship in philosophy at the University of Marburg. His colleagues there included Rudolf Bultmann, Nicolai Hartmann, Paul Tillich, and Paul Natorp. His students at Marburg included Hans-Georg Gadamer, Helene Weiss, Karl Löwith, Hannah Arendt, Gerhard Krüger, Leo Strauss, Jacob Klein, Günther Anders, and Hans Jonas. Following Aristotle, he began developing in his lectures the main theme of his philosophy: the question of the sense of being. He expanded the concept of subject to include history and concrete existence, finding this prefigured in Christian thinkers such as Paul of Tarsus, Augustine of Hippo, Martin Luther, and Søren Kierkegaard. He also read Wilhelm Dilthey, Husserl, Max Scheler, and Friedrich Nietzsche.

In 1927, Heidegger published *Sein und Zeit* (*Being and Time*). His primary motive was to qualify for a full professorship. The book did far more: it gave him international intellectual visibility.

**Freiburg**

When Husserl retired as professor of philosophy in 1928, Heidegger accepted Freiburg’s offer to succeed him, despite a counteroffer from Marburg. His 1929 inaugural lecture was titled "What is Metaphysics?" That same year, he published *Kant and the Problem of Metaphysics*.

Heidegger remained at Freiburg im Breisgau for the rest of his life, turning down later offers, including one from the Humboldt University of Berlin.