This volume collects the most intimate writings of one of the foremost French thinkers of the twentieth century on the central topic of his oeuvre. These essays, aphorisms, notes, and lectures on nonknowledge, sovereignity, and sacrifice clarify and extend Bataille's radical theology, his philosophy of history, and his ecstatic method of meditation. The "system" that emerges from his body of work is "atheology", a study of the effects of nonknowledge.