by: Shahbod Noori

From the ancient city of Ray to the medical schools of Europe — the story of a man who, more than a thousand years ago, believed that science should begin with observation, experience, and the courage to question

Some names belong not merely to a city or a nation, but to the history of humanity itself. Muhammad ibn Zakariya al-Razi is one of those names.

More than a thousand years ago, when many illnesses were still explained through superstition and the boundaries between medicine, philosophy, and ancient belief were often unclear, a remarkable man emerged from the historic Iranian city of Ray.

He observed. He experimented. He questioned. And perhaps most importantly, he was willing to challenge even the most respected medical authorities when his own clinical observations suggested something different.

His name was Abu Bakr Muhammad ibn Zakariya al-Razi, the Persian physician, philosopher, scientist, and medical scholar later known in the West as Rhazes.

Born around 865 CE in Ray, near present-day Tehran, al-Razi would eventually become one of the most influential physicians of the medieval world.

But his greatness was not simply the result of the number of books he wrote or the range of subjects he studied. What makes al-Razi especially fascinating today is the way he thought.

A Man Who Wanted to See for Himself

Ancient medicine was dominated by the enormous authority of figures such as Hippocrates and Galen. Their writings shaped medical thinking for centuries.

Al-Razi respected and studied these earlier masters, but respect did not mean unquestioning obedience.

He compared their ideas with what he actually observed in his patients.

For al-Razi, something written in an important book was not automatically the final word.

The patient had to be examined.

Symptoms had to be observed.

Treatments had to be evaluated.

And when observation did not agree with accepted theory, the theory itself could be questioned.

That attitude sounds surprisingly modern.

Al-Razi lived centuries before laboratories, microscopes, modern clinical trials, antibiotics, X-rays, or medical imaging. Yet the intellectual method behind much of his work resembles one of the foundations of modern science:

Observe, compare, test, and draw conclusions from evidence.

Treating the Patient, Not Only the Disease

One of the most remarkable features of al-Razi’s medical writings is his attention to individual patients.

His works did not simply contain lists of illnesses and remedies. They also included clinical observations describing symptoms, the progression of illnesses, treatments, and outcomes.

Hundreds of clinical observations have been identified within his enormous body of medical writing.

Today, recording a patient’s history and monitoring the response to treatment are basic parts of medicine. More than a millennium ago, however, such systematic clinical attention was extraordinary.

Al-Razi’s approach also reflected something deeper: medicine was about more than identifying a disease. The physician had to understand the human being suffering from it.

Historical accounts describe his concern for poor patients and his belief that medical care carried an ethical responsibility.

For al-Razi, medicine was not merely a profession.

It was a human obligation.

Smallpox and Measles: A Landmark in Medical History

Among al-Razi’s best-known contributions was his careful discussion of smallpox and measles.

Today, physicians clearly recognize these as different diseases. More than a thousand years ago, however, distinguishing illnesses with similar outward symptoms was far more difficult.

In his celebrated treatise on smallpox and measles, al-Razi described their symptoms and clinical differences with unusual attention.

The work became important far beyond the Persian-speaking world. It was translated into other languages, including Latin, and continued to attract medical attention centuries after his death.

The significance of his work was greater than simply describing two diseases.

It demonstrated the importance of distinguishing between conditions that might initially appear similar by carefully studying their signs and symptoms.

Modern physicians call this process differential diagnosis.

It remains one of the central skills of clinical medicine.

Al-Hawi: The Work of a Lifetime

If one book could symbolize al-Razi’s extraordinary medical career, it would probably be Kitab al-Hawi fi al-Tibb, commonly known simply as Al-Hawi, or The Comprehensive Book on Medicine.

Al-Hawi was no ordinary medical textbook.

It became an enormous collection of medical knowledge, bringing together material from earlier physicians alongside al-Razi’s own observations, comments, clinical experiences, and judgments.

This is where one can clearly see one of the most important characteristics of his scientific personality.

Al-Razi cited previous authorities, but he did not stop there.

He frequently added his own observations and conclusions.

The message was clear: the greatness of an earlier physician did not make further investigation unnecessary.

For al-Razi, science was never a place where questioning had to end.

Centuries later, Al-Hawi was translated into Latin and became known in Europe as the Liber Continens. His medical writings circulated widely in the European world and were among the works consulted by physicians and students.

Imagine the scene:

Centuries ago, a European medical student could open a major medical text whose author was a Persian physician from the city of Ray.

That alone tells us something extraordinary about the movement of knowledge across civilizations.

A Physician Who Also Understood the Mind

Another fascinating aspect of al-Razi’s work was his interest in the psychological and emotional dimensions of human life.

He wrote a work commonly known as Spiritual Medicine, dealing with character, behavior, emotions, reason, and the pursuit of a balanced life.

This broader approach reminds us that al-Razi did not view human beings simply as collections of physical symptoms.

The patient’s state of mind mattered.

The physician’s behavior mattered.

Hope, fear, judgment, and human relationships mattered.

For a physician working more than a thousand years ago, this was a remarkably broad view of health.

Not Everyone Should Be Allowed to Practice Medicine

Al-Razi also wrote about the responsibilities and qualifications of physicians.

He understood a truth that remains essential today: simply claiming to possess medical knowledge should never be enough to place another person’s life in one’s hands.

A physician needed knowledge, practical ability, experience, and ethical conduct.

Historical studies of al-Razi’s writings show his concern with distinguishing competent physicians from unqualified practitioners.

More than a millennium later, modern societies require medical education, examinations, supervised training, licensing, and professional standards.

The underlying principle is remarkably similar:

Human life is too valuable to be entrusted to someone who is not qualified to practice medicine.

Far More Than a Physician

Yet describing Muhammad ibn Zakariya al-Razi only as a physician would also underestimate him.

His intellectual interests extended into philosophy, pharmacology, chemistry, nutrition, and other areas of scientific inquiry.

Historical sources attribute a very large number of works to him, although not all have survived.

His investigations of substances and laboratory procedures also gave him an important place in the history of chemistry.

Modern historical scholarship requires some caution here. Popular accounts sometimes credit al-Razi with specific discoveries that cannot always be established with certainty from surviving evidence.

And perhaps there is no better way to honor a scientist than to treat his own history scientifically.

What can be said with confidence is that al-Razi contributed significantly to the study and classification of substances, experimental procedures, pharmacy, and the relationship between chemical knowledge and medicine.

The Hospital and a Famous Experiment

One of the most famous stories associated with al-Razi concerns the selection of a location for a hospital in Baghdad.

According to the traditional account, pieces of meat were placed in different areas of the city. The location where the meat decomposed most slowly was considered to have healthier air and was therefore preferred as a site for the hospital.

The story has been repeated for generations, although its precise historical details cannot be verified to the standards expected of a modern scientific report.

Still, its survival is revealing.

For centuries, people remembered al-Razi as the kind of man who would attempt to answer a practical question through observation and experiment rather than assumption.

Whether every detail of the story occurred exactly as later generations described it is less important than what the story tells us about the scientific reputation he left behind.

From Ray to Europe

Perhaps the most extraordinary chapter of al-Razi’s story unfolded after his lifetime.

He died around 925 CE in Ray.

But his books did not die with him.

His medical works traveled across languages, cultures, and continents.

Major works were translated into Latin, and his name — transformed into Rhazes — became familiar to generations of European scholars.

Al-Hawi and other medical writings associated with him circulated in Europe for centuries. During the early age of European printing, his works were printed and studied alongside those of other major authorities of medicine.

This is why al-Razi should not simply be remembered as a symbol of national pride.

His influence is part of the documented history of the international exchange of knowledge.

Ideas developed and recorded in places such as Ray and Baghdad eventually reached medical scholars thousands of miles away.

Knowledge crossed borders long before the modern world made international communication easy.

Why Al-Razi Still Matters

More than a thousand years have passed since Muhammad ibn Zakariya al-Razi practiced medicine.

Modern hospitals contain technologies he could never have imagined.

Physicians can see inside the human body without surgery. They can study DNA, transplant organs, replace damaged joints, perform robotic surgery, and treat diseases that were once almost certain death sentences.

So why should a physician from the ninth and tenth centuries still matter?

Because the instruments of science have changed enormously, but the spirit of science has not.

A physician must still observe.

A physician must still ask questions.

Similar diseases must still be distinguished from one another.

Treatments must still be evaluated.

Accepted ideas must still be reconsidered when evidence proves them wrong.

And perhaps most importantly, behind every medical chart, every laboratory result, and every diagnosis, the physician must still see a human being.

That is why the story of al-Razi remains relevant after more than a millennium.

Iran’s Gift to the History of Medicine

Honoring Muhammad ibn Zakariya al-Razi is therefore about much more than remembering a famous physician from the distant past.

It is also a celebration of a civilization that, during one of the great intellectual periods of its history, placed enormous value on knowledge, inquiry, medicine, philosophy, and the search for answers.

It is the story of a man who emerged from Ray, yet whose ideas traveled far beyond Iran.

His books were translated.

Generations of physicians studied his work.

European scholars knew him as Rhazes.

And more than a thousand years after his lifetime, Muhammad ibn Zakariya al-Razi continues to hold an important place in the history of medicine.

Perhaps the most meaningful way to honor him is not to surround him with legends, but to remember what his scientific life represented:

The courage to question.
The freedom to think.
Respect for observation and evidence.
And responsibility toward human life.

That is the enduring legacy of Muhammad ibn Zakariya al-Razi — a Persian scholar from the ancient city of Ray whose name became part of the history of science itself.