Philosopher and theologian, a major influence on 20th-c existentialism, born in Copenhagen. He studied theology, philosophy, and literature at Copenhagen, and came to criticize purely speculative systems of thought, such as Hegel's, as irrelevant to existence-making choices. For Hegel's rationalism, Kierkegaard substituted the disjunction Enten-Eller (1843, Either/Or). In Afsluttende Uvidenskabelig Efterskrift (1846, Concluding Unscientific Postscript), he attacked all philosophical system building, and formulated the thesis that subjectivity is truth. Other works include (trans titles) The Concept of Irony (1841), Fear and Trembling (1843), and The Sickness unto Death (1849).
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