Søren Aabye Kierkegaard, born in Copenhagen in 1813 and deceased in 1855, was a Danish philosopher, theologian, poet, and social critic, widely regarded as the first existentialist philosopher. Throughout his career, he wrote critical texts on organized religion, Christianity, morality, ethics, psychology, and philosophy of religion, showing a particular fondness for figures of speech such as metaphor, irony, and allegory.