AlRazi

al-Razi, also known as Rhazes in Latin sources, was Abu Bakr Muhammad ibn Zakariya al-Razi, a Persian polymath who lived from about 865 to 925 CE. He is one of the most celebrated physicians of the Islamic Golden Age and wrote extensively on medicine, chemistry, and philosophy. Born in Ray, near modern Tehran, he studied and practiced in centers such as Baghdad, contributing to the development of medical science in the medieval world.

Medicine: He produced a vast medical encyclopedia, al-Hawi fi al-Tibb (The Comprehensive Book on Medicine), drawing on earlier authorities as well as his own clinical observations. The work was later translated into Latin and Hebrew and had a lasting influence on European medicine. He is credited with early descriptions that helped distinguish smallpox from measles and with systematic clinical observations and case reports, emphasizing differential diagnosis and empirical reasoning.

Chemistry and philosophy: In addition to medicine, al-Razi wrote on alchemy and early chemistry, including treatises that discuss transformations of substances and distillation. His writings in philosophy engaged with Aristotelian and Neoplatonist ideas and sometimes critiqued Galen.

Legacy: al-Razi's emphasis on observation and experimentation influenced later scholars in the Islamic world and Europe; his name rhazes became standard in Latin translations. He died circa 925 CE in Ray.