The Canon of Medicine (Arabic: القانون في الطب, romanized: al-Qānūn fī l-ṭibb; Persian: قانون در طب, romanized: Qānun dar Teb; Latin: Canon Medicinae) is an encyclopedia of medicine in five books compiled by Persian physician-philosopher Avicenna (ابن سینا, ibn Sina) and completed in 1025.

"Canon" (often translated in English as "law" or "legal code") here connotes an ordered system, or complete, universal encyclopedia.

[12] Book 1 is made up of six theses which give a general description of medicine in general, the cosmic elements that make up the cosmos and the human body, the mutual interaction of elements (temperaments), fluids of the body (humours), human anatomy, and physiology.

The temperaments are reported to be the interaction between the four different element's qualities, such as the conflict between dryness, wetness, cold, and hot.

[13]: 57–65 The Canon also adopted the ancient theory of Four Temperaments and extended it to encompass "emotional aspects, mental capacity, moral attitudes, self-awareness, movements and dreams".

comparison of a member to itself The Canon continues to explain the sun's position in relation to ideal temperament and the role that climate and human skin play.

Avicenna says that the hand, especially the palm and the tip of the index finger, is the most sensitive of all and attuned to tactile contact.

Medicine is described as "hot" or "cold", not based upon its actual temperature but with regard to how it relates to the temperament of the human body.

Further description of youth in regards to heat and moisture is given with respect to sex, geographical location, and occupation.

[16] An element of such belief is apparent in the chapter of al-Lawa, which relates "the manifestations to an interruption of vital life essence to the brain."

He combined his own view with that of the Four Humours to establish a new doctrine to explain the mechanisms of various diseases in another work he wrote, Treatise on Pulse:[citation needed] "From mixture of the four [humors] in different weights, Allah Almighty [God the most high] created different organs; one with more blood like muscle, one with more black bile like bone, one with more phlegm like brain, and one with more yellow bile like lung.

Then, that part which goes to the brain to keep it vital and functioning, becomes colder and wetter, and in its composition the serous softness and phlegm vapor dominate.

Avicenna describes healthy blood as "red in colour, has no unpleasant odour, and has a very sweet taste."

[citation needed] The atrabilious humor is considered dry and cold, created from sediment of good blood.

[13]: 99 In the thesis on General Physiology or "The Faculties of the Body", Avicenna separates life into three different categories: Vital, Natural, and Animal.

[13]: 110–11 Book 2 (the Materia Medica) of the Canon alphabetically lists about 800 "simple" medical substances that were used at the time.

The information presented in Book 3 of the Canon of Medicine represents some of Avicenna's most important contributions to several fields of study, including atherosclerosis,[23] pulsology,[24] migraines,[25] cataracts,[26] vasovagal syncope,[27] and neuroscience.

[29][11] Following this description of the causes of stroke, Avicenna discusses how the blocking agents are derived from the blood or phlegm humors, and how these are most abundant in people with wet and cold natures.

[29] Finally, Book 3 discusses several treatments for stroke including the use of herbal medicines and "non-pharmacological interventions such as venesection and dry or wet cupping on the lower neck and upper back".

[29] Book 3 also contains an extensive chapter about neuroscience, which "begins by explaining the structure and function of the nervous system, ...parts of the brain, the spinal cord, the ventricles, meninges, nerves and roots, ... [and] neurological and neuropsychological disorders, including signs and symptoms and treatment strategies".

[30] Furthermore, several specific neurological conditions are described, including: epilepsy, apoplexy and stroke, paralysis, vertigo, spasm, wry mouth, tremor, meningitis, amnesia and dementia, head injuries and traumas, hysteria and conversion disorder, fainting and stupor, nervous tic, sexual disorders, love sickness, delusion and hallucination, insomnia, sopor, nightmare, mania and psychosis, melancholia, paranoia, asthenia, hydrocephalus, and sciatica.

[30] Book 3 of the Canon of Medicine also describes fifteen kinds of headaches, as well as descriptions of treatments for each of these conditions that are divided into three steps:[30] 1.

Compound medicines Surgical intervention and other non-pharmacological strategies were also recommended in some cases, such as electrical shocks to treat epilepsy.

[30] Book 4 covers diseases that affect the whole body such as fevers or poisons, or conditions that could happen to any part of it such as wounds or bone fractures.

"[31] In Book 4 – as with other ancient Islamic medical writings – large sections were devoted to covering fevers in great detail.

[12] Several types of fevers were distinguished, partly based on the location of the factors causing each specific illness:[12] 1.

Hectic (occurring in a major organ) Each of these classifications were further subdivided: for example, Avicenna also listed 23 different types of ephemeral fevers in Book 4 of the Canon of Medicine.

(Confusingly, there appear to have been two men called Gerard of Cremona, both translators of Arabic texts into Latin.

Ostler states that it was the later of these, also known as Gerard de Sabloneta, who translated the Qanun (and other medical works) into Latin in the 13th century.

"[36] George Sarton wrote in the Introduction to the History of Science:[37] "The Qanun is an immense encyclopedia of medicine.