Our Approach · Origins · The Iranian Plateau
The Iranian Plateau · c. 500 BCE to 1037 CE
Ancient Persia
Where a competence test for surgeons was written into scripture.
Persian medicine has two layers. Zoroastrian scripture ranked three kinds of healer, by knife, by herb, and by holy word. A thousand years later Avicenna completed the Canon of Medicine in 1025 and built the whole system on mizaj, the temperament each person carries. Health was the balance belonging to that patient, and treatment returned them to it. Those physicians were reading a regulated bodily state without instruments. The Unified Model of Tone names that state tone and measures it.
forthcoming
Era
Zoroastrian Avesta to Avicenna's Canon of 1025
Region
The Iranian plateau, and the Abbasid schools it fed
Source texts
The Vendidad; al-Razi's case books; the Canon of Medicine
Living descendant
Unani medicine, regulated in India under the Ministry of Ayush
The documentary record
What the record shows
Two separate bodies of work carry the Persian argument. These are the dated points that hold each of them in place.
The Vendidad is a law book inside the Zoroastrian Avesta. At Fargard 7.44 it names three kinds of healer: one who cures with the knife, one with herbs, and one with the manthra, the holy word. (Darmesteter, 1898)
The ranking is the record's own. Persian scripture placed an input with no substance at the top of its list of medicines.
Fargard 7.36 to 40 sets a competence test for the surgeon. Three patients treated with the knife who recover qualify him for life. Three who die disqualify him for life. (Vendidad 7)
Outcome decided who was allowed to practice. No older rule qualifying a physician to practice survives anywhere, though the Code of Hammurabi had priced a physician's liability some fifteen centuries earlier.
Fargard 20 credits Thrita with founding the healing art and describes ten thousand healing plants sent down around the tree of eternal life. (Vendidad 20)
Plant medicine and word medicine have separate origin stories inside one scripture. The tradition kept them apart from the start.
The Vendidad is composed in Younger Avestan. Scholarship generally places the text itself in the Parthian period, roughly 141 BCE to 224 CE, though the date of its first redaction is contested. (Livius)
Anything that reads the Canon of Medicine as an outgrowth of Zoroastrian scripture is off by roughly a millennium.
The Bukhtishu were a Nestorian family of physicians from Gondeshapur in Khuzestan who served the courts of Baghdad from the eighth century to the eleventh. (Encyclopaedia Iranica)
The Persian medical inheritance reached the Abbasid schools through named people holding named posts. That is why the transmission can be dated at all.
Al-Razi was born in Rayy near modern Tehran in 865 and died there about 925. More than a thousand of his case histories survive. (National Library of Medicine)
The Persian record is clinical and individual. It follows named patients through the course of an illness rather than illness in the abstract.
Avicenna was born near Bukhara in 980 and died in 1037. He completed the Canon of Medicine in 1025, in five books running from general principles to compound remedies. (National Library of Medicine)
One work covered the whole of medicine. A single system could therefore govern practice across two civilizations at once.
Gerard of Cremona translated the Canon into Latin in the twelfth century. Some sixty editions of part or all of it were printed in Europe between 1500 and 1674, mostly for university medical training. (National Library of Medicine)
Persian medicine set the curriculum in European medical faculties from the twelfth century to the seventeenth. Its assumptions about the body became theirs.
Vendidad, Fargard 7
Persian scripture ranked its healers and put the spoken word first
Fargard 7.44 tells a patient who has a choice among the three healers to take the one who cures with the manthra. Knife and herb work on the substance of the body. The manthra was ordered sound, recited in exact rhythm and register, and it worked on the state of the person hearing it.
The same chapter regulates the trade. Fees are fixed by the patient's rank, from an ox of low value for a householder up to a chariot and four for the lord of a province. A priest is healed for a blessing.
Fargard 7.36 to 40 then sets the entry rule. A healer who loses three patients under the knife is barred for life, and one who brings three through is licensed for life. Persian scripture regulated the physician before it regulated the medicine.
One who heals with the knife, one who heals with herbs, and one who heals with the Holy Word, let one apply to the healing by the Holy Word.
The Vendidad, Fargard 7.44 · translated by James Darmesteter, Sacred Books of the East, 1898Asha and druj
Health was a body held in the order that holds everything else
Asha is the governing word of Zoroastrian thought. It means truth, right order, and the arrangement that keeps the sun on its path. Its opposite is druj, the lie, the state of a thing pulled out of true.
Sickness belonged to druj. Zoroastrian illness named a state of the whole person, not a lesion in a part, and healing meant taking the side of order against it.
Two of the divine powers around Ahura Mazda carry the same idea in their names. Haurvatat means wholeness and is bound to the waters. Ameretat means deathlessness and is bound to the plants. In ritual, water and plants stand in for those two powers directly.
The response to sickness was to name it and drive it out. Fargard 21 calls the clouds down by the thousand drops to destroy sickness and death, then sets the turn of the day against the turn of the illness. If death comes at eve, may healing come at night. Recovery was expected to arrive on a rhythm.
Vendidad 10.19
Zoroastrian purity started at the level of thought
Zoroastrian practice compresses to three words in a fixed order: good thoughts, good words, good deeds. Thought comes first, and word and deed follow from it.
The Vendidad applies the sequence to the person directly. At Fargard 10.19 it says that anyone in the world can win purity for himself when he cleanses himself with good thoughts, words, and deeds. Fargard 5.21 calls that purity the greatest good after life itself.
That is a moral formula, and a healer working inside it inherited its order of operations. Fear, anger, and grief change breathing, heart rhythm, and muscle tone before they are named as feelings.
765 CE, Baghdad
A thousand years separate the two Persian medicines
The Zoroastrian material and the medicine of al-Razi and Avicenna are two traditions. The Vendidad is Younger Avestan, most plausibly composed in the Parthian period. Al-Razi died about 925 and Avicenna finished the Canon in 1025.
What connects them is a route rather than a doctrine. Gondeshapur in Khuzestan held a hospital going back to Sasanian times, and its physicians moved north. Jurjis ibn Bukhtishu, who directed that hospital, was summoned to Baghdad in 765 to treat the caliph al-Mansur.
His family served the caliphs and their successors from the second half of the eighth century to the second half of the eleventh. Greek, Syriac, Indian, and Persian material was translated into Arabic along that route, and the medicine it produced was a new synthesis.
Rhazes of Rayy
Al-Razi wrote medicine down one patient at a time
Abu Bakr Muhammad ibn Zakariya al-Razi, known in Latin as Rhazes, was born in Rayy in 865 and died there about 925. He wrote a general textbook, the Kitab al-Mansuri, and left working files of readings and personal observations that his students assembled after his death as the Kitab al-Hawi.
More than a thousand of his case histories survive. They record what he saw, what he did, and what happened next, which makes them the closest thing the tenth century has to a clinical notebook.
His treatise on smallpox and measles separates the two diseases by the weight of their early signs. Back pain runs strongest in smallpox. Nausea and anxiety run strongest in measles. Both diseases are then handled by what the patient shows rather than by what the disease is called.
The Canon, 1025
Avicenna's Canon governed medical teaching for six centuries
Ibn Sina, known in Europe as Avicenna, was born near Bukhara in 980 and died in 1037. He wrote the Canon of Medicine while traveling west across Iran, beginning in Gurgan and finishing in Hamadan in 1025.
The Canon runs to five books. The first sets out general principles, the second lists simple drugs, the third works through the body head to toe, the fourth covers fevers and injuries, and the fifth gives compound remedies.
Gerard of Cremona carried it into Latin in the twelfth century, and European faculties were still teaching from it in the seventeenth. Andrea Alpago, who died in 1522, went back to the Arabic and corrected the Latin against it.
Mizaj
Mizaj set what counted as normal for one person and for nobody else
Mizaj is temperament: the balance of hot, cold, wet, and dry that a given body holds. Avicenna treats it as the foundation of the whole system. Every diagnosis begins by establishing what balance this patient is supposed to have.
The Canon states that a perfectly equable temperament does not exist in any human being. Health is the range around each person's own value.
Avicenna writes that a body taking on the temperament proper to a different population would fall ill, and might die, because the value it was defending had been replaced by somebody else's. Treatment therefore aimed at return rather than at improvement.
No single healthy number exists to push a patient toward. The physician locates that patient's own baseline, reads how far the body has drifted from it, and chooses an input to close the gap.
One must realize that every individual person has a temperament entirely peculiar to himself, and it is impossible for any other person to have an identical temperament.
Avicenna, The Canon of Medicine, Book I · translated by O. Cameron Gruner, 1930Reading the pulse
The pulse was read against that patient's own temperament
The Canon lists ten features of the pulse that report the state of the body. Six of them: the size of the expansion, the force of the impact, the resistance of the artery, the length of the pauses, the evenness of successive beats, and the rhythm of the whole.
Avicenna then gives the pulse expected in a hot temperament, a cold one, a moist one, and a dry one. The reading is never absolute. A pulse counts as high or low against the value that patient is supposed to hold.
He also assigns each emotional state its own pulse. Anger makes it large, high, swift, and brisk. Joy makes it large, soft, and slow. Grief makes it small, weak, and sluggish. Sudden fear makes it quick and disorderly, and prolonged fear makes it vary with the shading of the anxiety.
Stages of illness
Illness was tracked as a course with four named stages
The Canon divides many diseases into onset, increment, acme, and decline. Each stage has its own signs, and the same division applies to the illness as a whole and to each attack inside it.
What is correct at onset is wrong at the acme, and a physician who misreads the stage works against the course of the disease.
Al-Razi's smallpox treatise is built the same way. Its chapters run in order through prevention, hastening the eruption, ripening the pustules, drying them, and guarding the bowels afterward. He wrote his chapters in the order the illness moves.
Regimen and the hand
Treatment was graded input aimed at the middle from either side
The Canon gives a whole division to keeping health rather than to curing disease. It prescribes regimens for each period of life, for the aged, for shifts of climate and season, and for travelers. Season and stage of life decide the treatment.
The hand is specified as precisely as the drugs. The Canon sorts friction into hard, soft, repeated, moderately hard, rough, and gentle, and sets an aim for each grade. Hard friction braces. Soft friction relaxes. Rough friction draws blood to the surface and gentle friction holds it in one place.
The Canon gives the object directly: friction is applied to make thin persons heavier and heavy persons thinner, to brace the flabby and to soften those who are not pliable enough. One input, applied with judgment, moves people in opposite directions toward the same middle.
Structural work sits in the same system. The Canon devotes chapters to spinal deformity, dislocation, and fracture, and treats them with massage, cupping, dry heat, phlebotomy, drugs, and surgery according to the level and kind of injury.
Unani today
Unani medicine still runs on mizaj, and India regulates it
Unani carries the Canon's system from the Islamic world into South Asia, and it is practiced today. India recognizes it as one of the systems under the Ministry of Ayush, created in 2014, with education regulated by the National Commission for Indian System of Medicine under an Act of 2020.
India reported 53,126 registered Unani practitioners as of 1 January 2024, and 54 undergraduate Unani colleges with an admission capacity of 3,307 students as of 1 April 2024. The World Health Organization published benchmarks for training in Unani medicine in 2010 and revised them in 2022.
The doctrine has not drifted. The Government of India describes temperament as the most important principle of Unani medicine, and describes disease as a pathological shift in temperament that treatment reverses by returning the person to the normal one. Avicenna made that claim in 1025, and it is still the operative one.
The convergence
What Persia documented, and what it is called now
Persian physicians had no instruments beyond their hands and their eyes. They worked from the pulse, the skin, the sleep, and the manner of the patient. Out of that came a system built around a regulated state. Each person holds it at their own value, and treatment returns them to it. Independent traditions across the world reached the same short list of observations, which is evidence that the state itself is real and readable by an unaided observer. The Unified Model of Tone names that state tone and measures it.
- Mizaj is the temperament of one person, and the Canon says no two people share one. A patient moved to somebody else's balance was expected to fall ill.Set point, the value a system defends and returns to.
- Avicenna located the body's slow injury in the steady loss of the moisture it was made from, and wrote the regimens for each age and for the aged around that loss.Load, the accumulated demand a system carries over time.
- Disease is divided into onset, increment, acme, and decline, and the correct handling changes at each stage.Time course, where the stage of a process decides what the right input is.
- Friction is graded hard, soft, repeated, moderately hard, rough, or gentle, and is chosen to make thin people heavier and heavy people thinner.Input quality, where the character of an input decides the response.
- Regimen is written separately for the seasons and for shifts of climate, and the pulse itself is expected to change with them.Oscillation, the rhythms that carry regulation.
Common questions
Frequently asked
What is mizaj?
Mizaj is the hot, cold, wet, and dry balance a particular body holds, and Avicenna's Canon of Medicine makes it the first thing a physician establishes about a patient. The Canon states that a perfectly equable temperament exists in no human being, and that every individual holds one no other person can match. Treatment therefore aims to bring the patient back to their own mizaj, and there is no universal standard of health to aim at instead.
What is Avicenna's Canon of Medicine?
The Canon of Medicine is the medical encyclopedia Ibn Sina completed in 1025, written while he traveled west across Iran. It runs to five books: general principles, simple drugs, the body head to toe, fevers and injuries, and compound remedies. Gerard of Cremona translated it into Latin in the twelfth century, and some sixty editions of part or all of it were printed in Europe between 1500 and 1674, mostly for university medical training.
Who was Rhazes, and what did he contribute?
Rhazes is the Latin name of Abu Bakr Muhammad ibn Zakariya al-Razi, born in Rayy near modern Tehran in 865 and died there about 925. He wrote the Kitab al-Mansuri and left the working files published after his death as the Kitab al-Hawi. More than a thousand of his case histories survive. His treatise on smallpox and measles separates the two by their early signs, with back pain strongest in smallpox and nausea strongest in measles.
Why did the Vendidad rank the holy word above the knife and the herb?
The Vendidad names three healers at Fargard 7.44, one who cures with the knife, one with herbs, and one with the manthra, and it tells a patient with a choice to take the third. Knife and herb work on the substance of the body. The manthra was ordered sound recited in exact rhythm, and it worked on the state of the person hearing it. Zoroastrian scripture treated that state as the deeper of the two targets.
Did the ancient Persians know about the nervous system?
No. Neither the Zoroastrian texts nor the Islamic-era physicians had an anatomy of nerves as regulators. What they had was a system built on a state each person holds at their own value, read at the pulse and in the skin and the sleep, and moved by graded input. Avicenna assigned every emotion its own pulse, which places feeling inside the body as a physical event. They described the behavior of a system whose wiring they could not see.
Is Unani medicine still practiced?
Yes. Unani is the living descendant of the Persian and Arabic tradition the Canon of Medicine codified, and India regulates it as one of the systems under the Ministry of Ayush. India reported 53,126 registered Unani practitioners as of 1 January 2024 and 54 undergraduate Unani colleges as of 1 April 2024. The World Health Organization published benchmarks for training in Unani medicine in 2010 and issued a revised edition in 2022.
What does the Unified Model of Tone say about Persian medicine?
That Persian physicians were reading tone without instruments and describing it with precision. Mizaj is a set point held at a value that belongs to one person. The four stages of disease treat illness as a course rather than a fixed thing. Graded friction moves thin people and heavy people toward the same middle. The model does not adopt the four qualities as a mechanism. It holds that the state those physicians tracked is the state it now measures.
Keep reading
Where this connects
- Tone is the regulated state Persian physicians read at the pulse, defined and measured.
- Set point is the modern name for what mizaj was tracking, a value one body holds and defends.
- Load is what Avicenna was managing when he wrote a different regimen for every stage of life.
- Time course is why a physician who misread the stage of an illness was treating the wrong thing.
- Input quality is why hard, soft, rough, and gentle friction were prescribed for opposite results.
- Oscillation is why the Canon expects a pulse to read differently in spring than in winter.
- Ancient Greece supplied the four qualities the Canon rebuilt, and read health as balance in the same way.
- Mesopotamia worked the same corner of the world earlier, and left the first written diagnostic handbooks.
- Ancient Israel shared the region and the era, and put rest and rhythm at the center of its law.
Sources
References
- Darmesteter, J. The Zend-Avesta, Part I: The Vendidad. Sacred Books of the East, American Edition, 1898. Fargard 7.
- Darmesteter, J. The Zend-Avesta, Part I: The Vendidad. Fargard 10, on purity through good thoughts, words, and deeds.
- Darmesteter, J. The Zend-Avesta, Part I: The Vendidad. Fargard 20, Thrita and the origins of medicine.
- Darmesteter, J. The Zend-Avesta, Part I: The Vendidad. Fargard 21, the healing litany and the invocation of Airyaman.
- Lendering, J. Avesta. Livius: Articles on Ancient History.
- Schlerath, B. and Skjærvø, P. O. AṢa. Encyclopaedia Iranica.
- Encyclopaedia Iranica. Amurdad, the Ameša Spenta of immortality, paired with Haurvatat and the waters.
- Encyclopaedia Iranica. Bokhtishu, ancestor of a Syro-Persian Nestorian family of physicians.
- Devenny, J. A. Bukhtishu. New Catholic Encyclopedia, reproduced by Encyclopedia.com.
- National Library of Medicine. Islamic Medical Manuscripts: Bio-Bibliographies, al-Razi.
- National Library of Medicine. Islamic Medical Manuscripts: Ibn Sina, Kitab al-Qanun fi al-tibb.
- Gruner, O. C. A Treatise on the Canon of Medicine of Avicenna, Incorporating a Translation of the First Book. Luzac, London, 1930.
- Greenhill, W. A. (trans.) A Treatise on the Small-Pox and Measles, by Abu Becr Mohammed ibn Zacariya ar-Razi. Sydenham Society, London, 1848.
- Markatos, K. et al. Spine deformities and trauma in Avicenna's Canon of Medicine. International Orthopaedics, 43(5), 2019.
- Ghaffari, F. et al. Spinal Traumas and their Treatments According to Avicenna's Canon of Medicine. World Neurosurgery, 84(1), 2015.
- Ministry of Ayush, Government of India. Ayush in India 2024.
- World Health Organization. WHO benchmarks for the training of Unani medicine. Geneva, 2022.
- Mojahedi, M. et al. The weight of Mizaj (temperament) indices in Persian Medicine: a Delphi study. Caspian Journal of Internal Medicine, 2023.
Last updated 2026-08-10