Razi

Muhammad ibn Zakariyā Rāzī (Mohammad-e Zakariā-ye Rāzi: Persian: محمد زکریای رازی), known as Rhazes or Rasis after medieval Latinists, (August 26, 865, Rayy— 925, Rayy) was a Persian  physician, alchemist and chemist, philosopher, and scholar. He is recognised as a polymathm and Biographies of Razi, based on his writings, describe him as “perhaps the greatest clinician of all times.” Numerous “firsts” in medical research, clinical care, and chemistry are attributed to him, including being the first to differentiate smallpox from measles, and the discovery of numerous compounds and chemicals including alcohol and kerosene, among others. Edward Granville Browne considers him as "probably the greatest and most original of all the physicians, and one of the most prolific as an author".

Although Rhazes (or Razi) was a Persian living in Iran, his work was published in both Persian and Arabic lanugages, as such was the case for most Persian scientists during this era. Such multi-lingual publications in Persia were analogous to the later usage of the Latin language for scientific publications in Europe in the following centuries.

Rhazes made fundamental and enduring contributions to the fields of medicine, alchemy, music, and philosophy, recorded in over 200 books and articles in various fields of science. He was well-versed in Persian, Greek and Indian medical knowledge and made numerous advances in medicine through own observations and discoveries.

Well educated in music, mathematics, philosophy, and metaphysics, he finally chose medicine as his professional field. As a physician, he was an early proponent of experimental medicine and is considered the father of pediatrics. He was also a pioneer of neurosurgery and ophthalmology. He was among the first to use Humoralism to distinguish one contagious disease from another. In particular, Razi was the first physician to distinguish smallpox and measles through his clinical characterization of the two diseases. And as an alchemist, Rhazes is known for his study of sulfuric acid and for his discovery of ethanol and its refinement to use in medicine. He became chief physician of Rayy and Baghdad hospitals. Razi Invented what today is known as rubbing alcohol.

Rhazes was a rationalist and very confident in the power of ratiocination; he was widely regarded by his contemporaries and biographers as liberal and free from any kind of prejudice and very bold and daring in expressing his ideas without a qualm.

He traveled extensively but mostly in Persia. As a teacher in medicine, he attracted students of all disciplines and was said to be compassionate and devoted to the service of his patients, whether rich or poor.