al-Razi, Abu Bakr Muhammad ibn Zakariyya’ (d. 925)

Perhaps the most famous and widely respected Islamic authority on medicine in the medieval period, al-Razi also aspired to a comparable achievement in philosophy and the other sciences such as alchemy. His success in these other subjects, however, was seldom recognized either in his own time or later; in philosophy, for example, more writers cite him for purposes of rejection and refutation than for admiration and emulation. However, his ideas were and are important. Chief among his positive contributions is his advocacy of a doctrine of equal aptitude in all humans, which grants no special role for unique and divinely favoured prophets and which recognizes the possibility of future progress in the advancement of knowledge. Philosophically, al-Razi was by his own admission a disciple of Socrates and Plato, much of whose teaching he knew on the basis of the latter’s Timaeus. Accordingly, he was noted for upholding the eternity of five primary principles, God, soul, time, matter and space, and for a concept of pleasure that sees it as the return to a normal harmony following a serious deviation or disruption which is itself pain.