Abu Bakr Muhammad Ibn Zakariy.
Al-Razi (865 - 925)
Razi achieved master in a number of fields,initially,he was interested in music but later on he learnt medicine,mathematics,astronomy.Al-Razi was a Hakim, an alchemist and a philosopher.In medicine,his cobtribution was so significiant that it can only be compared to that of Ibn-e-Sina.Some of his works in medicine e.g. Kitab al-Mansoori,Al-Hawi,Kitab al-Mulooki and Kitab al-Judari wa al-Hasabah earned everlasting fame.
Al-Razi followed a pattern that had been introduces earlier by Galen but in it,Al-Razi attempted to correct several errors made by Galen himself.