Abu Bakr alRazi

Abū Bakr Muḥammad ibn Zakariyyā al-Rāzī, known in the Latin West as Rhazes, was a Persian polymath of the Islamic Golden Age whose work left an enduring imprint on the fields of medicine, alchemy, philosophy, and the natural sciences. Born in the city of Rey in the ninth century and active during the Abbasid era, he became one of the most celebrated physicians of the medieval world. A prolific scholar, he authored more than two hundred treatises covering medicine, logic, ethics, and metaphysics, and his writings were widely translated and studied across the Islamic world and later in medieval Europe. His clinical knowledge, experimental approach, and humanistic attitude toward patients established him as one of the most influential medical thinkers in history.

Early Life and Background

Al-Rāzī was born in Rey, near modern Tehran, into a Persian family. Rey’s location on the historic Silk Road facilitated exchanges of knowledge and culture, and the city provided a fertile intellectual environment. After his early years in Rey, he travelled to Baghdad, where he studied, practiced, and taught medicine at local bīmāristāns (hospitals). His skill as a physician soon earned him a reputation, leading to appointments as the chief physician in hospitals in both Baghdad and Rey.
When invited back to his native city by the governor Mansur ibn Ishaq, he took charge of the Rey hospital and dedicated to the governor two medical works: The Spiritual Physic and al-Manṣūrī fī al-Ṭibb. His growing renown prompted further invitations to Baghdad, where he oversaw a prominent hospital founded by al-Muʿtaḍid and later participated in the planning of a new medical institution under al-Muqtāfi. His method for choosing the hospital’s site—observing where pieces of meat decayed most slowly—reflected his early adoption of empirical, evidence-based decision-making.
In his later years he returned permanently to Rey, where he eventually lost his sight. Accounts concerning the cause of his blindness vary; some describe head trauma, others dietary habits. Regardless, he remained intellectually active and continued teaching until shortly before his death, traditionally placed around 925 CE.

Teaching and Personal Ethos

Al-Rāzī’s lectures were famed for attracting large groups of students, organised in concentric circles around him. Questions would be passed through successive groups, reaching al-Rāzī himself only if none of the students could answer. This structure underscores his prestige as a shaykh as well as his dedication to cultivating independent thought among his students.
He is remembered as compassionate and charitable. He treated poor patients without charge and composed a practical manual entitled Man lā Yaḥḍuruhu al-Ṭabīb (“For One Who Has No Physician to Attend Him”), aimed at offering medical guidance to those unable to afford professional care.

Contributions to Medicine

Al-Rāzī’s influence on medical science was profound and wide-ranging. His extensive writings and innovative techniques helped shape the development of clinical practice, pharmacology, and medical ethics.
Early experimental medicineHe is recognised as an early advocate of empirical methods in medical diagnosis and treatment. He consistently emphasised observation, case analysis, and experimentation, and he compared treatment outcomes to determine the efficacy of medical procedures.
Pediatrics, obstetrics, and ophthalmologyHe has been called the father of pediatrics for his specialised attention to care for children and for treating diseases affecting them. His writings also contain early insights into obstetrics and diseases of the eye.
Smallpox and measlesOne of his most renowned contributions is the work Kitāb al-Judrī wa’l-Ḥaṣbah (“On Smallpox and Measles”), among the earliest texts to distinguish clinically between the two diseases. The treatise was translated into Syriac, Greek, Latin, and various European languages, making it a cornerstone of medieval medical curricula.
Neurology and meningitisAl-Rāzī compared the outcomes of different treatment methods for meningitis, including bloodletting, reflecting his use of comparative clinical observation.
Pharmacy and medical apparatusHe helped systematise the early practice of pharmacy. His writings describe the preparation of compounds such as mercury-based ointments and list the tools used in dispensaries—mortars, flasks, spatulas, and phials—many of which remained standard instruments for centuries.
Medical ethicsAl-Rāzī displayed a strong ethical orientation. He criticised fraudulent practitioners and warned against over-reliance on “miracle cures.” At the same time, he cautioned against arrogance among trained physicians, urging humility, continuous learning, and honest communication with patients.

Contributions to Philosophy and the Sciences

Beyond medicine, al-Rāzī wrote on metaphysics, ethics, logic, and astronomy. Although only fragments of his philosophical work survive—often transmitted by critics—he is known to have formulated a doctrine involving five eternal principles. His writings also included notable critiques of prophetic revelation and religious authority, placing him among the more heterodox thinkers of the medieval Islamic world.
His engagement with alchemy, though characteristic of the era, also contributed to early chemical theory and practice. He described apparatus, classified substances, and made observations that anticipated later developments in chemistry.

Influence and Legacy

Al-Rāzī’s influence extended far beyond his lifetime. Through translation into Latin and adoption in European universities, his medical writings shaped the education of late medieval and early Renaissance physicians. Works such as al-Manṣūrī and On Surgery formed part of the standard curriculum in Western medical faculties.
Medieval European catalogues record numerous manuscripts of his treatises, illustrating their wide circulation. Scholars such as Edward Granville Browne have hailed him as one of the greatest and most original physicians of the Islamic world, while others have emphasised his pioneering role in child health, clinical observation, and experimental methodology.