The Proof of Islam Imam Abu Hamid Muḥammad ibn Muhammad al-Ghazali (d. 1111)-jurist, legal theorist, logician, theologian, and mystic was a master of both the outer and inner sciences of the Shari'ah who is regarded by many as the greatest Muslim thinker to have lived after the Pious Predecessors. Credited with dealing a death blow to Aristotelian philosophy in the Muslim world and bringing authentic Islamic spirituality into the mainstream, his life and thoughts were highly influential in shaping medieval society's spiritual values and practices and are no less relevant today.