Søren Kierkegaard

1813 – 1855

Søren Aabye Kierkegaard was a Danish theologian and philosopher widely considered the first existentialist thinker. His major works—including Either/Or (1843), Fear and Trembling (1843), The Concept of Anxiety (1844), and The Sickness Unto Death (1849)—pioneered an indirect, often pseudonymous form of philosophical writing that addressed individual existence, anxiety, despair, and the leap of faith. He profoundly influenced 20th-century existentialism, phenomenology, theology, and literature.

Last checked: May 10, 2026, 1:06 PM