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(rā`zēz) or


(rā`sĭs, –zĭs), 860–932, Persian physician. He was chief physician at the Baghdad hospital. An observant clinician, he formulated the first known description of smallpox as distinguished from measles in a work known as Liber de pestilentia (tr. A Treatise on Smallpox and Measles, 1848). His works were widely circulated in Arabic, and Greek versions and were published in Latin in the 15th cent. They include a textbook of medicine called Almansor and an encyclopedia of medicine compiled posthumously from his papers and known as Liber continens.



(or Rasis; Latin forms of Razi; full Arabic name, Abu Bakr Muhammad Ibn Zakariya al-Razi). Born 865 in Rey; died there 925 or 934. Iranian scholar, encyclopedist, physician, and philosopher; rationalist and freethinker.

Rhazes supervised clinics first in Rey and later in Baghdad. He was very familiar with the science, medicine, and philosophy of antiquity. He apparently wrote some 184 works in all, of which 61 have come down to us. These works dealt with philosophy, ethics, theology, logic, medicine, astronomy, physics, and chemistry (alchemy). His works were translated into Latin in Europe between the tenth and 13th centuries.

Rhazes’ scientific studies are characteristically free of dogmatism, utilize experimentation, and display a practical orientation. His philosophical thought, resembling certain kinds of gnosticism, is based on a doctrine of five eternal principles: creator, soul, matter, time, and space. Reason, sent by the creator, inspires the soul, which is imprisoned by matter, to strive for liberation; the path to liberation is the study of philosophy. The atomism of Rhazes is similar to that of Democritus. Rhazes believed in absolute space and absolute time, and he accepted the existence of a multiplicity of worlds. In ethics, he attacked asceticism and urged an active life in society, on the model of Socrates.

Rhazes sharply criticized all the religions that existed in his time. He wrote the antireligious treatise Mashariq al-anbiya (The Dawn of the Prophets), which evidently served as the basis for the medieval Latin lampoon entitled De tribus impostoribus. According to Rhazes, truth was one but religions were many; consequently, all religions were false, and one should read not Scripture, but the books of philosophers and scientists. His antireligious statements provoked fierce attacks by Muslim thinkers of the tenth and 11th centuries, particularly Farabi.


Rhazes’ principal medical works are al-Hawi (Continent of Medicine) and the ten-volume Book of Medicine Dedicated to Mansur. They are unique medical encyclopedias in Arabic; translated into Latin, they served as a guide to physicians for centuries. In On Smallpox and Measles (Russian translation in V. O. Gubert, Smallpox and Smallpox Vaccination, vol. 1, St. Petersburg, 1898), Rhazes gave a classic description of these diseases, noting immunity to repeated infection; he is known to have made use of vaccination (variolation).

Rhazes is believed to have introduced the practice of writing a medical history for each patient. He was the first to describe an instrument for removing foreign bodies from the pharynx and one of the first to use cotton wadding in bandaging and catgut in sewing up wounds. He drew up instructions for equipping hospitals and choosing hospital sites. Among his other works are One Physician Cannot Cure All Diseases, which takes up the importance of specialization among doctors, and Medicine for Those Who Have No Doctor, about medical aid and self-help for the poor.



Epître de Beruni contenant le répertoire des ouvrages de Muhammad b. Zakariya ar-Razi. Published by P. Kraus. Paris, 1936.
Abu Bekr Muhammedis fillii Zachariae Raghensis (Razis): Opera philoso-phica fragmentaque quae supersunt, part 1. Collected and edited by P. Kraus. Cairo, 1939.
Nadjmabadi, M. Bibliographie de Razes. Tehran, 1960.
Razi, ibn Zakariya al-, Muhammad. Al-Sirat al-falsafiya. Edited by P. Kraus. Tehran, 1964.
Mohaghegh, M. Filseif-i-Rayy Muhammad Ibn-i-Zakariya-i-Razi. Tehran, 1974.
In Russian translation:
Karimov, U. I. Neizvestnoe sochinenie ar-Razi: “Kniga tainy tain.” Tashkent, 1957.
References in periodicals archive ?
Manuscripts were as Kitab al-hawi fi al-tibb (Comprehensive Book on Medicine) authored by Rhazes (9th-10th centuries; Rhazes 2005), Kitab al-Qanun fi al-Tibb (Canon of Medicine) and Kitab al-adwiya al-qalbiya (The treatise on cardiac drugs) of Avicenna (10th-11th century; Ibn Sina 1998; Ibn Sina 2009), Ikhtiyarat-i Badil (Selections for Badi'i) written by Hajji Zayn al-Attar (14th century; al-Ansari 1992), Tuhfat al-mu'minin (Present for the Faithful) of Daylami Tunakabuni (17th century; Tunakabuni 2007), and finally Makhzan al-adviyah (The Storehouse of Medicaments) by Alavi Shirazi (18th century; Shirazi 2009).
We already know that people such as Al-Farabi, Avicenna, Al-Khawrizmi and Rhazes rose to prominence in the post-Islamic era.
13 Zakariya Razi (850-923 AD) also known as Rhazes explained treatment of Busoore labaniya (acne) appearing over the face and nose in his prodigious text Al Hawi (The Virtuous Life).
Al Kindi, Al Ghazali, Rhazes, Avicenna and Averroes) built their theories of medicine and psychology around a framework based on teachings from the Quran and the Hadith.
The arguments stated above are true for all ancient people including many eminent scholars like Rhazes, Khayyam and Anvari.
Hippocrates described bandages smeared with resin, while Rhazes, an Arabian surgeon of the 9th century, used linen soaked in lime mixed with egg white, which would stiffen into a firm dressing.
The first written evidence of spinach in the Mediterranean are in three tenth-century works, the medical work by al-Razi (known as Rhazes in the West) and in two agricultural treatises, one by Ibn Wahshiya and the other by Qustus al-Rum.
El estudio se basaba en la lectura de los textos mas destacados de Hipocrates, Galeno, Rhazes y Avicena, especialmente, que el estudiante debia aprender de memoria para luego repetir el contenido de esas obras, y en elaborar larguisimos recetarios.
Rhazes claimed that firstly liver occurred in fetus, Ibn Sina claimed umbilical cord, Hippocrates said brain is the first organ in fetus but, contrarily Mansur b.
unparalleled names of Ferdowsi, Rumi, Rhazes, Rudaki, Biruni, Al-Farabi,
The Islamic philosopher-physician Rhazes made a crucial contribution by clearly differentiating between measles and smallpox in his Treatise on Smallpox and Measles of 910.