Abu Bakr Muhammad ibn Zakariya ar-Razi, also known as Rhazes, was born at Ray (near Tehran) in Persia. The actual years of his birth and death are uncertain. An Arabic physician and scientist, Rhazes is today recognized as one of the original portrayers of disease. Like many medieval scholars, Rhazes mastered a wide range of subjects, including philosophy, music (he wrote an encyclopedia on the subject), poetry, and logic. His interest in medicine apparently did not arise until he was in his thirties, when it is said that he was stimulated by a chance encounter with an apothecary. At various times he taught and practiced in Baghdad, where he also served as director and chief physician in that city's hospital. Very little is known of Rhazes' personal life, but it is believed that he was often persecuted for his open mindedness and beliefs in equality.

Rhazes rejected all...