Martin Heidegger (; German: [ˈmaʁtiːn ˈhaɪdɛɡɐ]; 26 September 1889 – 26 May 1976) was a German philosopher best known for contributions to phenomenology, hermeneutics, and existentialism. His work covers a wide range of topics including ontology, technology, art, metaphysics, humanism, language and history of philosophy. He is often considered to be among the most important and influential philosophers of the 20th century, specially in the continental tradition.
In April 1933, Heidegger was elected as rector at the University of Freiburg and was widely criticized for his membership and support for the Nazi Party during his tenure. After World War II he was dismissed from Freiburg and banned from teaching after denazification hearings at Freiburg. There has been controversy about the relationship between his philosophy and Nazism.
In Heidegger's first major text, Being and Time (1927), Dasein is introduced as a term for the type of being that humans possess. Heidegger believed that Dasein already has a "pre-ontological" and concrete understanding that shapes how it lives, which he analyzed in terms of the unitary structure of "being-in-the-world". Heidegger used this analysis to approach the question of the meaning of being; that is, the question of how entities appear as the specific entities they are. In other words, Heidegger's governing "question of being" is concerned with what makes beings intelligible as beings.
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