Abu Sahl Masihi
Abu Sahl Isa Ibn Yahya Masihi was a Persian philosopher, physician, mathematician and astronomer. There is little information about his life. He was contemporary with the great scholars: Abu Rayhan Biruni, Avicenna and Ibn al-Khammar. Fakhr al-Din Razi (one of the most celebrated theologians and exegesists of Islam; 1149-1209), considered him as a great Muslim philosopher in the Islamic world.
His views on different scientific fields
####Medicine:
Abu Sahl was an expert physician. Some historians believe that he was Avicenna’s master in medicine. But Avicenna himself did not name any one as his teacher in medicine: “I studied all the ancient medical books and in a short time, I became proficient in medicine inasmuch as it was not a difficult science”. Anyway Abu Sahl is considered to be more proficient than Avicenna in medicine. About the centre of sense in body, which was one of the most important medical discussions in the ancient medicine, Galen and his disciples considered the brain as the centre of sense and the most important organ in body. Although Abu Sahl was one of the disciples of Galen, his idea was different form him; like Aristotle and Avicenna, Abu Sahl believed that, heart is the centre of life power not brain. Despite his celebrity among Muslim philosophers, he was not known by Europeans, and his works were not translated. European translators translated only the medical books in which there was a treatment section for diseases, like the Canon of Medicine (Avicenna’s famous work). But Abu Sahl was against details in treatment sections of medical books, he believed that in medical books the theoretical sections (including general bases, the principles of prevention) should be written in details and the treatment section should be brief with explanations.
Astronomy and mathematics:
There are not left any books on mathematics and astronomy from him, but according to Avicenna and the letters which were written to Abu Rayhan Biruni, it can be inferred that Abu Sahl was profoundly versed in these sciences. Avicenna wrote in the preface of his work “On Angel”: “There was a discussion between me and Abu Sahl on angel, I wrote my idea in a tratise and asked Abu Sahl to appraise my work”. This note indicates that Abu Sahl was superior to Avicenna in mathematics and perhaps was his master. Moreover 12 mathematics and astronomy books were written for Biruni by Abu Sahl. Therefore some historians know him as Biruni’s teacher. Although Biruni names Abu Sahl in his works but never knows him as teacher.
Published works:
1- Asnaf al-Ulum (The classes of sciences) this treatise was written for “Abul Hasan Suheili”. All the branches of sciences were written. Some parts of this treatise was translated into English.
In manuscript:
1- Resalat al-Adwiya (Treatise of Drugs)
2- Arkan al-Aalam (The Elements of the Universe)
3- The Principles of Pulse
4- God’s Mystery on the Creation of Man (the first sections of the book are about heart and the respiratory system and the last section is on the womb
5- Book on Cholera
6- On physical Constitution
7- On Poetry
8- Treatise on Blister and its treatment
9- The General Medicine (one of his most famous work. It contains 2 sections; the first section talks about the general medical bases, such as: physiology, hygiene, nourishment, sleeping and waking, etc. The second section, first talks about the diseases of the organs from top to the bottom of body, then names some of the general diseases, skin and bone diseases and at the end the special medicine for these diseases and also its formulation)
10- The one Hundred Sections (his greatest and most famous work; it is somehow a medical encyclopedia)
11- The Principles of Creation
12- Nawader al-Hukama, etc.
The lost works:
1- The Principles of Geometry
2- On the Soul
3- The Short Almagest
4- Interpretation of Dreams
5- On the Rules of Calligraphy
6- Al-Narjesiyeh, etc
Sources :
Islamic encyclopedia