Philosopher of the Heart is the groundbreaking biography of renowned existentialist S�ren Kierkegaard's life and creativity, and a searching exploration of how to be a human being in the world. S�ren Kierkegaard is one of the most passionate and challenging of all modern philosophers, and is often regarded as the founder of existentialism. Over about a decade in the 1840s and 1850s, writings poured.