Al-Ghazali 1058 – 1111

Abu Hamid al-Ghazali was an 11th and early 12th-century Persian Sunni Muslim theologian, jurist, philosopher, and Sufi mystic, regarded as one of the most influential thinkers in the history of Islam. His 40-volume The Revival of the Religious Sciences, written after he abandoned a prestigious teaching position to pursue Sufi spiritual practice, is a comprehensive synthesis of Islamic ethics, ritual, and inner spiritual life. His earlier book The Incoherence of the Philosophers attacked the Aristotelian metaphysics of al-Farabi and Avicenna, prompting a major response a century later from Averroes in The Incoherence of the Incoherence. He played a central role in integrating Sufism into mainstream Sunni theology and in defining what would count as orthodox Islamic belief. His thought has been compared, for its philosophical importance and its autobiographical Deliverance from Error, with that of Augustine.