Søren Aabye Kierkegaard

The Sickness Unto Death is a book written by Danish philosopher Søren Kierkegaard in 1849 under the pseudonym Anti-Climacus. A work of Christian existentialism, the book is about Kierkegaard's concept of despair, which he equates with the Christian concept of sin, particularly original sin.

Stages on Life's Way is a philosophical work by Søren Kierkegaard written in 1845. The book was written as a continuation of Kierkegaard's masterpiece Either/Or. While Either/Or is about the aesthetic and ethical realms, Stages continues onward to the consideration of the religious realms. Kierkegaard's "concern was …