al-Awfāq

Abu Hamid al-Ghazali (1058–1111), born in Tus in Khorasan, became the most celebrated scholar of his age as a professor at the Nizamiyya college in Baghdad. Then, in 1095, a spiritual crisis left him unable to speak in class. He gave up his post, lived for years as a wandering Sufi in Damascus and Jerusalem, and returned convinced that true knowledge comes from experience as well as reason.

His Incoherence of the Philosophers challenged the followers of Aristotle and provoked a famous reply from Ibn Rushd; his Revival of the Religious Sciences became one of the most read books in Islam; and his autobiography, The Deliverance from Error, is still studied, and was quoted by William James in The Varieties of Religious Experience.