Søren Kierkegaard

Kierkegaard is considered the father of existentialism. Writing under various pseudonyms, he explored themes of anxiety, despair, faith, and the individual's relationship to existence.

He challenged the systematic philosophy of Hegel by insisting on the primacy of subjective, individual experience. His concept of the "leap of faith" and his analysis of anxiety as the "dizziness of freedom" remain foundational in existential thought.