Which work is NOT written by Soren Kierkegaard?

The work that is not written by Soren Kierkegaard is "Being and Time." This significant philosophical analysis was authored by Martin Heidegger, who became a key figure in existentialism and phenomenology. In "Being and Time," Heidegger explores the nature of Being and introduces concepts such as "Dasein," which refers to human existence.

On the other hand, the other works listed—"The Sickness Unto Death," "Either/Or," and "Fear and Trembling"—are all foundational texts by Kierkegaard. "The Sickness Unto Death" examines despair and the human condition from a Christian existential viewpoint. "Either/Or" presents a philosophical discussion on aesthetic versus ethical living, while "Fear and Trembling" delves into the biblical story of Abraham and Isaac, addressing themes of faith and ethics. Each of these works reflects Kierkegaard's distinctive contributions to existential thought and his exploration of individual experience.