One of the most remarkable documents to have come down from classical Islamic civilisation, this autobiography of the most influential thinker of medieval Islam (1058-1111 C.E.) describes his education and his intellectual crisis, which left him so paralysed by doubt that he was forced to resign the most distinguished academic appointment. His faith returned after years of wandering and seeking, during which time he achieved direct knowledge of God in the form of the illuminative experience of the Sufis.