The Canon of Medicine () is an encyclopedia of medicine in five books compiled by Ibn Sina (, Avicenna) and completed in 1025. It is among the most influential works of its time. It presents an overview of the contemporary medical knowledge of the Islamic world, which had been influenced by earlier traditions including Greco-Roman medicine (particularly Galen), Persian medicine, Chinese medicine and Indian medicine. Its translation from Arabic to Latin in 12th century Toledo greatly influenced the development of medieval medicine. It became the standard textbook for teaching in European universities into the early modern period.
The Canon of Medicine remained a medical authority for centuries. It set the standards for medicine in medieval Europe and the Islamic world and was used as a standard medical textbook through the 18th century in Europe. It is an important text in Unani medicine, a form of traditional medicine practiced in India.
Title The English title Canon of Medicine is derived from the common medieval Latin Canon Medicinae, itself a translation of the original Arabic (), with the same meaning. "Canon" (often translated in English as "law" or "legal code") here connotes an ordered system, or complete, universal encyclopedia. The common medieval version of the title was Liber Canonis.
Development The medical traditions of Galen, and thereby Hippocrates, had dominated Islamic medicine from its beginnings. Avicenna sought to fit these traditions into Aristotle's natural philosophy. He began writing the Canon in Gorganj, continued in Rey and completed it in Hamadan in 1025. The result was a "clear and ordered "summa" of all the medical knowledge of Ibn Sīnā's time". It served as a more concise reference in contrast to Galen's twenty volumes of medical corpus.
Overview
The Canon of Medicine is divided into five books: Essays on basic medical and physiological principles, anatomy, regimen and general therapeutic procedures. List of medical substances, arranged alphabetically, following an essay on their general properties. Diagnosis and treatment of diseases specific to one part of the body Diagnosis and treatment of conditions covering multiple body parts or the entire body. Formulary of compound remedies.
Books 1, 3, and 4 are each further divided into parts (fanns), chapters (ta’līms), subchapters (jumlahs), sections (faṣls), and subsections (bābs).
Book 1 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 book explains the causes of health and disease. Avicenna believed that the human body cannot be restored to health unless the causes of both health and disease are determined. He defined medicine (tibb) as follows:
Thesis I Definition and Scope of Medicine Avicenna begins part one by dividing theoretical medicine and medical practice. He describes what he says are the "four causes" of illness, based on Aristotelian philosophy: The material cause, the efficient cause, the formal cause, and the final cause:
Material Cause: Avicenna says that this cause is the human subject itself, the "members or the breath" or "the humours" indirectly. Efficient Cause: The efficient cause is broken up into two categories: The first is "Extrinsic", or the sources external to the human body such as air or the region we live in. The second efficient cause is the "Intrinsic", or the internal sources such as our sleep and "its opposite-the waking state", the "different periods of life", habits, and race. Formal Cause: The formal cause is what Avicenna called "the constitutions; the compositions". According to Oskar Cameron Gruner, who provides a treatise within Avicenna's Canon of Medicine, this was in agreement with Galen who believed that the formal cause of illness is based upon the individual's temperament. Final Cause: The final cause is given as "the actions or functions".
Thesis II The Elements of Cosmology Avicenna's thesis on the elements of the cosmos is described by Gruner as "the foundation of the whole Canon". Avicenna insists here that a physician must assume the four elements that are described by natural philosophy, although Avicenna makes it clear that he distinguishes between the "simple" element, not mixed with anything else, and what we actually experience as water or air, such as the sea or the atmosphere. The elements we experience are mixed with small amounts of other elements and are therefore not the pure elemental substances. The "light" elements are fire and air, while the "heavy" are earth and water:
The Earth: Avicenna upholds Aristotelian philosophy by describing Earth as an element that is geocentric. The Earth is at rest, and other things tend towards it because of its intrinsic weight. It is cold and dry. The Water: Water is described as being exterior to the sphere of the Earth and interior to the sphere of the Air, because of its relative density. It is cold and moist. "Being moist, shapes can be readily fashioned (with it), and as easily lost (and resolved)." The Air: The position of Air above Water and beneath Fire is "due to its relative lightness". It is "hot and moist", and its effect is to "rarefy" and make things "softer". The (sphere of the) Fire: Fire is higher than the other elements, "for it reaches to the world of the heavens". It is hot and dry; it traverses the substance of the air, and subdues the coldness of the two heavy elements; "by this power it brings the elementary properties into harmony."
Thesis III The Temperaments The Canon of Medicine divides the thesis on temperaments into three subsections; a general overview, one based on members of the body, and temperaments based on age.
I The Temperaments (General description) 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. Avicenna suggests that these qualities battle between each other until an equilibrium state is reached and this state is known as the temperaments.
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". This expanded theory of four temperaments is given in the following table:
+ Evidences of the four primary temperaments Evidence Hot Cold Moist Dry Morbid states Inflammations become febrile Loss of vigour Fevers related to serous humour Rheumatism Lassitude Functional power Deficient energy Deficient digestive power Difficult digestion Subjective sensations Bitter taste Excessive thirst Burning cardiac orifice Lack of desire for fluids Mucoid salivation Sleepiness Insomnia, wakefulness Physical signs High pulse rate, approaching lassitude Flaccid joints Diarrhea Swollen eyelids Rough skin Acquired habitFoods & medicines Calefacients harmful Infrigidants harmful Moist aliments harmful Dry regimen harmful Infrigidants beneficial Calefacients beneficial Humectants beneficial Relation to weather Worse in summer Worse in winter Bad in autumn
The Eight Varieties of Equipoise Canon describes humans as having eight different "varieties of equipoise", or differing temperaments. The temperaments fall under two categories; In relation to beings other than men and in relation to the individual himself.
A. In relation to beings other than men i. "the equability of the temperament seen in man as compared with other creatures" ii. the temperament of other human beings Avicenna describes a hot versus cold / moist versus dry equilibrium between the members of the human body. The heart, for example, is hot and must be in equilibrium of other cold parts of the body such as the brain. When this equilibrium between these members are achieved, the person is considered to be in "ideal equability". iii. external factors "such as race, climate, atmosphere" This third gauge for temperament assumes that each race has their own equilibrium. As an example he says, "The Hindus, in health, have a different equability to the Slaves, and so on." Avicenna explains that the differing climates contribute to differing temperaments among the races. iv. in relation to extreme climates B. In relation to the individual himself v. "as compared to another person" Although Avicenna had listed the fifth mode "as compared to another person", he seems to contradict that statement by explaining that every individual has a temperament that is unique to themselves and unlike anyone else. vi. comparison of the individual himself vii. comparing one member of the body with another member of the body The Canon here makes the distinction of the members into categories of their individual "moistness", "dryness", "hotness", and "coldness". viii. 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. Organs are nowhere near ideal in temperament, but skin comes the closest. 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.
The Canon then describes when temperaments are unequal, in other words, illness. Avicenna separates these into two categories, which are fairly self explainable within the context of what he had already defined as the temperaments. A. Simple "intemperaments" Hot temperament (hotter than normal) Cold temperament (colder than normal) Dry temperament (drier than usual) Moist temperament (more moist than usual)
B. Compound "intemperaments" The compound intemperaments are where two things are wrong with the temperament, i.e. hotter and moister; hotter and drier; colder and moister; colder and drier. There are only four because something cannot be simultaneously hotter and colder or drier and moister. The four simple temperaments and four compound intemperaments can each be divided into "Those apart from any material substance" and "Those in which some material substance is concerned", for a total of sixteen intemperaments. Examples of the sixteen intemperaments are provided in the "third and fourth volumes."
II The Temperament of the Several Members Each member of the body is described to be given each its individual temperament, each with its own degree of heat and moisture. Avicenna lists members of the body in "order of degree of Heat", from hottest to coldest. The breath and "the heart in which it arises"; The blood; which is said to be generated from the liver; The liver, which may be looked upon as concentrated blood; The flesh, which would be as hot as the liver were it not for the nervous tissue which pervades it; The muscles, which are cooler than the flesh because of their tendons and ligaments, as well as the nerves; The spleen, which is colder because of the faex of the blood; The kidneys; The wall of the arteries; The veins; The skin of the palms and soles.
Then a list is given of coldest members to hottest. The serious humour; The hairs; The bones; The cartilage; The ligaments; The tendon; The membranes; The nerves; The spinal cord; The brain; The fat; The oil of the body; The skin.
Then a list is given in order of moisture. Avicenna credits Galen with this particular list. The serious humour The blood The oil the fat the brain the spinal cord the breasts and the testicles the lung the liver the spleen the kidneys the muscles the skin
Finally, a list is given in order of dryness the hair the bone cartilage ligaments tendons sereous membranes arteries veins motor nerves heart sensory nerves skin
III The Temperaments Belonging to Age