To answer this question, Guy Stagg tells the story of three of the twentieth century’s most original minds: the philosopher Ludwig Wittgenstein, the poet and painter David Jones, and the writer Simone Weil. All three went on retreat during times of crisis, to find their work and their lives changed for ever. Seeking to understand these experiences, Stagg follows Wittgenstein to the ancient monastery outside Vienna where he recovered from depression, sails to the isolated island off the Welsh coast where Jones discovered a new way to make art, and spends Lent at the forbidding French Abbey that sparked an epiphany in Weil’s thinking. The World Within blends a moving personal account with history, biography and travel, offering a profound exploration of the impulse to withdraw. It asks why retreat still enchants people to this day and hints at how each one of us can find a sanctuary of our own.