Stranger lives than Henry Sidgwick's have resulted from the philosophical quest for the ultimate truth about the Universe, but his is nonetheless a source of considerable fascination. As a Victorian philosopher, social scientist, literary critic, educator, reformer, and parapsychologist, an academic who spent nearly his entire adult life teaching at and reforming Cambridge University, Sidgwick was at the philosophical heart of England when England was at the height of its worldly power. He was friendly with everyone from William Gladstone to George Eliot, had in one brother-in-law a future prime minister and in another a future archbishop of Canterbury, and served as a leading figure in that most famous of elite secret discussion societies, the Cambridge “Apostles,” which would go on to give the world the Bloomsbury circle and the Cambridge spies.