Persian scholar
Islamic Golden Age |
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Name
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Abū ʿAlī
al-Ḥusayn ibn ʿAbd Allāh ibn Sīnā (Avicenna)
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Birth
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approximately 980 CE / 370 AH
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Death
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1037 CE / 428 AH
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School/tradition
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Islamic medicine
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Main interests
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Medicine, astronomy, alchemy, chemistry, ethics,
logic, mathematics,
metaphysics, philosophy, physics, poetry, science,
theology
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Notable ideas
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The works of Avicenna were long used in Islamic and European medical education, and influenced European physicists
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Influences
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Aristotle, Galen, Neoplatonism, al-Farabi, al-Biruni, Muslim physicians such as al-Kindi and al-Razi
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Influenced
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Al-Biruni, Omar Khayyám, Averroes, Scholasticism, Albertus
Magnus, Scotus, Thomas Aquinas,
Buridan, Benedetti, Galileo, Jann Rañeses
|
Abū
ʿAlī al-Ḥusayn ibn ʿAbd Allāh ibn Sīnā (Persian: ابن سينا - Arabic: ابن سينا) (c. 980 in
Afshana near Bukhara[1],
Khorasan – 1037 in Hamedan[2]), commonly
known in English by his Latinized name Avicenna (Gr. Ἀβιτζιανός),[3] was a Persian[4] Shi'a Muslim polymath: an astronomer, chemist, logician and mathematician, physicist and scientist, poet, soldier and statesman,
theologian, and foremost physician and philosopher of his time.[5]
He wrote almost 450 works on a wide range of subjects, of which around 240 have survived. In particular, 150 of the surviving
works concentrated on philosophy and 40 of them concentrated on
medicine.[6] His
most famous works are The Book of Healing and The Canon of Medicine, which was a standard medical text at many Islamic and European
universities up until the 18th century. Ibn Sīnā developed a medical system that combined his own personal experience with that
of Islamic medicine, the medical system of Galen,
Aristotelian metaphysics, and ancient
Persian, Mesopotamian and Indian medicine. Ibn Sīnā is regarded as the father of modern medicine,[7] particularly for his
introduction of systematic experimentation and quantification into the study of physiology,[8] his discovery of the contagious nature of infectious diseases,[9] the introduction of quarantine to limit the spread of
contagious diseases, the introduction of clinical
trials,[10] and the first descriptions on
bacteria and viral organisms.[11] He is also considered the
father of the fundamental concept of momentum in physics.[12]
George Sarton, the father of the history of
science, wrote in the Introduction to the History of Science:
Biography
Early life
Ibn Sīnā's life is known to us from authoritative sources. A biography, which is widely considered by foremost Arabicists to
have been composed by a disciple and later redacted, covers his first thirty years, and the rest are documented by his disciple
al-Juzjani, who was also his secretary and his friend.
He was born in Persia around 980 (370 AH) in
Afshana, his mother's home, a small city now part of Uzbekistan. His father, a respected
Ismaili scholar, was from Balkh of the Persian province of Khorasan, now part of Afghanistan, and was at the time of his son's birth the governor of a village in one of the Samanid Nuh ibn Mansur's estates. He had his son very carefully educated
at Bukhara. Ibn Sina's independent thought was served by an extraordinary intelligence and
memory, which allowed him to overtake his teachers at the age of fourteen.
Ibn Sīnā was put under the charge of a tutor, and his precocity soon made him the marvel of his neighbours; he displayed
exceptional intellectual behaviour and was a child
prodigy who had memorized the Quran by the age of 7 and a great deal of Persian poetry as well. From a greengrocer he learned arithmetic,
and he began to learn more from a wandering scholar who gained a livelihood by curing the sick and teaching the young.
However he was greatly troubled by metaphysical problems and in particular the works of
Aristotle. So, for the next year and a half, he also studied philosophy, in which he encountered greater obstacles. In such moments of baffled inquiry, he would leave his
books, perform the requisite ablutions, then go to the mosque, and continue in prayer till light
broke on his difficulties. Deep into the night he would continue his studies, and even in his dreams problems would pursue him
and work out their solution. Forty times, it is said, he read through the Metaphysics of Aristotle, till the words were imprinted on his memory; but their meaning was hopelessly obscure, until one
day they found illumination, from the little commentary by Farabi, which he bought at a
bookstall for the small sum of three dirhams. So great was his joy at the discovery, thus made by help of a work from which he
had expected only mystery, that he hastened to return thanks to God, and bestowed alms upon the poor.
He turned to medicine at 16, and not only learned medical theory, but also by gratuitous
attendance on the sick had, according to his own account, discovered new methods of treatment. The teenager achieved full status
as a physician at age 18 and found that "Medicine is no hard and thorny science, like mathematics and metaphysics, so I soon made great progress; I became an
excellent doctor and began to treat patients, using approved remedies." The youthful physician's fame spread quickly, and he
treated many patients without asking for payment.
Adulthood
His first appointment was that of physician to the emir, who owed him his recovery from a
dangerous illness (997). Ibn Sina's chief reward for this service was access to the royal
library of the Samanids, well-known patrons
of scholarship and scholars. When the library was destroyed by fire not long after, the enemies of Ibn Sina accused him of
burning it, in order for ever to conceal the sources of his knowledge. Meanwhile, he assisted his father in his financial
labours, but still found time to write some of his earliest works.
When Ibn Sina was 22 years old, he lost his father. The Samanid dynasty came to its
end in December 1004. Ibn Sina seems to have declined the offers of Mahmud of Ghazni, and proceeded westwards to Urgench in the modern
Uzbekistan, where the vizier, regarded as a friend of
scholars, gave him a small monthly stipend. The pay was small, however, so Ibn Sina wandered from place to place through the
districts of Nishapur and Merv to the borders of Khorasan, seeking an opening for his talents. Shams al-Ma'äli Kavuus, the
generous ruler of Dailam and central Persia, himself a poet and a
scholar, with whom Ibn Sina had expected to find an asylum, was about that date (1052) starved to
death by his troops who had revolted. Ibn Sina himself was at this season stricken down by a severe illness. Finally, at
Gorgan, near the Caspian Sea, Ibn Sina met with a friend,
who bought a dwelling near his own house in which Ibn Sina lectured on logic and astronomy. Several of Ibn Sina's treatises were written for this patron; and the
commencement of his Canon of Medicine also dates from his stay in Hyrcania.
Ibn Sina subsequently settled at Rai, in the vicinity of modern Tehran, (present day capital of Iran), the home town of Rhazes; where
Majd Addaula, a son of the last Buwayhid emir, was nominal ruler under the regency of his mother (Seyyedeh Khatun).
About thirty of Ibn Sina's shorter works are said to have been composed in Rai. Constant feuds
which raged between the regent and her second son, Amir Shamsud-Dawala, however, compelled the
scholar to quit the place. After a brief sojourn at Qazvin he passed southwards to Hamadãn, where
another Deylamite emir had established himself. At first, Ibn Sina entered into the
service of a high-born lady; but the emir, hearing of his arrival, called him in as medical attendant, and sent him back with
presents to his dwelling. Ibn Sina was even raised to the office of vizier. The emir consented that he should be banished from
the country. Ibn Sina, however, remained hidden for forty days in a sheikh's house, till a fresh
attack of illness induced the emir to restore him to his post. Even during this perturbed time, Ibn Sina persevered with his
studies and teaching. Every evening, extracts from his great works, the Canon and the Sanatio, were dictated and
explained to his pupils. On the death of the emir, Ibn Sina ceased to be vizier and hid himself in the house of an
apothecary, where, with intense assiduity, he continued the composition of his works.
Meanwhile, he had written to Abu Ya'far, the prefect of the
dynamic city of Isfahan, offering his services. The new emir of Hamadan, hearing of this
correspondence and discovering where Ibn Sina was hidden, incarcerated him in a fortress. War meanwhile continued between the
rulers of Isfahan and Hamadãn; in 1024 the former captured Hamadan and its towns, expelling the
Tajik mercenaries. When the storm had passed, Ibn Sina returned with the emir to Hamadan, and
carried on his literary labours. Later, however, accompanied by his brother, a favourite pupil, and two slaves, Ibn Sina escaped
out of the city in the dress of a Sufi ascetic. After a
perilous journey, they reached Isfahan, receiving an honourable welcome from the prince.
Later life
The remaining ten or twelve years of Ibn Sīnā's life were spent in the service of Abu Ja'far 'Ala
Addaula, whom he accompanied as physician and general literary and scientific adviser, even in his numerous campaigns.
During these years he began to study literary matters and philology, instigated, it is asserted, by criticisms on his style. He contrasts with the nobler and more
intellectual character of Averroes. A severe colic, which
seized him on the march of the army against Hamadãn, was checked by remedies so violent that Ibn Sina could scarcely stand. On a
similar occasion the disease returned; with difficulty he reached Hamadãn, where, finding the disease gaining ground, he refused
to keep up the regimen imposed, and resigned himself to his fate.
His friends advised him to slow down and take life moderately. He refused, however, stating that: "I prefer a short life
with width to a narrow one with length". On his deathbed remorse seized him; he bestowed his goods on the poor, restored
unjust gains, freed his slaves, and every third day till his death listened to the reading of the Qur'an. He died in June
1037, in his fifty-eighth year, and was buried in Hamedan,
Iran.
Works
Scarcely any member of the Muslim circle of the sciences, including theology,
philology, mathematics, astronomy, physics, and music, was left untouched by the treatises of Ibn Sīnā. This vast quantity of works - be they full-blown treatises
or opuscula - vary so much in style and content (if one were to compare between the 'ahd made with his disciple Bahmanyar
to uphold philosophical integrity with the Provenance and Direction, for example) that Yahya (formerly Jean) Michot has
accused him of "neurological bipolarity".
Ibn Sīnā wrote at least one treatise on alchemy, but several others have been falsely
attributed to him. His book on animals was translated by Michael Scot. His Logic, Metaphysics, Physics, and De Caelo, are treatises
giving a synoptic view of Aristotelian doctrine, though the Metaphysics demonstrates a significant departure from the brand of
Neoplatonism known as Aristotelianism in Ibn Sīnā's world; Arabic philosophers have hinted at the idea that Ibn Sīnā was
attempting to "re-Aristotelianise" Muslim philosophy in its entirety, unlike his predecessors, who accepted the conflation of
Platonic, Aristotelian, Neo- and Middle-Platonic works transmitted into the Muslim world.
The Logic and Metaphysics have been printed more than once, the latter, e.g., at Venice in 1493, 1495, and 1546. Some of his shorter essays on
medicine, logic, etc., take a poetical form (the poem on logic was published by Schmoelders in 1836). Two encyclopaedic treatises, dealing with philosophy, are often mentioned. The larger, Al-Shifa' (Sanatio), exists nearly complete in manuscript in the Bodleian Library and elsewhere; part of it on the De Anima appeared at Pavia (1490) as the Liber Sextus Naturalium, and the long account of Ibn Sina's philosophy given by
Muhammad al-Shahrastani seems to be mainly an analysis, and in many places a
reproduction, of the Al-Shifa'. A shorter form of the work is known as the An-najat
(Liberatio). The Latin editions of part of these works have been modified by the corrections which the monastic editors
confess that they applied. There is also a حكمت مشرقيه (hikmat-al-mashriqqiyya, in Latin Philosophia
Orientalis), mentioned by Roger Bacon, the majority of which is lost in antiquity, which
according to Averroes was pantheistic in tone.
Sciences
Medicine
-
About 100 treatises were ascribed to Ibn Sina. Some of them are tracts of a few pages, others are works extending through
several volumes. The best-known amongst them, and that to which Ibn Sina owed his European reputation, is his 14-volume
The Canon of Medicine, which was a standard medical text in Europe and the
Islamic world up until the 18th century.[13] The book is
known for its introduction of systematic experimentation and quantification into the study of physiology,[8] the discovery of contagious
diseases,[9] the introduction of
quarantine to limit the spread of infectious
diseases, the introduction of clinical trials,[14] and the first descriptions on bacteria and
viral organisms.[15] It classifies and describes diseases, and
outlines their assumed causes. Hygiene, simple and complex medicines, and functions of parts of
the body are also covered. In this, Ibn Sīnā is credited as being the first to correctly document the anatomy of the human eye,
along with descriptions of eye afflictions such as cataracts. It asserts that tuberculosis was contagious, which was later disputed by Europeans, but turned out to be true. It also
describes the symptoms and complications of diabetes. Both forms of facial paralysis
were described in-depth. In addition, the workings of the heart as a valve are described.
[citation needed]
A copy of the Canon of Medicine, dated 1593
An Arabic edition of the Canon appeared at Rome in 1593, and a Hebrew version at Naples
in 1491. Of the Latin version there were about thirty editions, founded on the original translation
by Gerard de Sablonetta. In the 15th century a commentary
on the text of the Canon was composed. Other medical works translated into Latin are the Medicamenta Cordialia,
Canticum de Medicina, and the Tractatus de Syrupo Acetoso.
It was mainly accident which determined that from the 12th to the 18th century, Ibn Sīnā should be the guide of medical study in European universities, and eclipse the names
of Rhazes, Ali ibn al-Abbas and Averroes. His
work is not essentially different from that of his predecessor Rhazes, because he presented the doctrine of Galen, and through Galen the doctrine of Hippocrates, modified by the system
of Aristotle, as well as the Indian doctrines of
Sushruta and Charaka.[16] But the Canon of Ibn Sīnā is distinguished from the Al-Hawi
(Continens) or Summary of Rhazes by its greater method, due perhaps to the logical studies of the former.
The work has been variously appreciated in subsequent ages, some regarding it as a treasury of wisdom, and others, like
Averroes, holding it useful only as waste paper. In modern times it has been seen of mainly
historic interest as most of its tenets have been disproved or expanded upon by scientific medicine. The vice of the book is
excessive classification of bodily faculties, and over-subtlety in the discrimination of diseases. It includes five books; of
which the first and second discuss physiology, pathology
and hygiene, the third and fourth deal with the methods of treating disease, and the fifth
describes the composition and preparation of remedies. This last part contains some personal observations.
He is, like all his countrymen, ample in the enumeration of symptoms, and is said to be inferior to Ali in practical medicine
and surgery. He introduced into medical theory the four causes of the Peripatetic system. Of natural history and
botany he pretended to no special knowledge. Up to the year 1650,
or thereabouts, the Canon was still used as a textbook in the universities of Leuven and
Montpellier.
In the museum at Bukhara, there are displays showing many of his writings, surgical instruments from the period and paintings of patients undergoing treatment. Ibn Sīnā was
interested in the effect of the mind on the body, and wrote a great
deal on psychology, likely influencing Ibn Tufayl and
Ibn Bajjah. He also introduced medical herbs.
Alchemy
As a chemist, Avicenna was the first to write refutations on alchemy. Four of these works were translated into Latin as:[17]
- Liber Aboali Abincine de Anima in arte Alchemiae
- Declaratio Lapis physici Avicennae filio sui Aboali
- Avicennae de congelatione et conglutinatione lapifum
- Avicennae ad Hasan Regem epistola de Re recta
In one of these works, Ibn Sīnā was the first to discredit the theory of the transmutation of substances commonly believed by alchemists:
"Those of the chemical craft know well that no change can be effected in the different species of substances, though they can
produce the appearance of such change."[18]
Among his works refuting alchemy, Liber Aboali Abincine de Anima in arte Alchemiae was the most influential, having
influenced later medieval chemists and alchemists such as Vincent of Beauvais.[17]
Aromatherapy
Ibn Sīnā used steam distillation to produce the first essential oils. As a result, he is regarded as a pioneer of aromatherapy.[19]
Astronomy
In 1070, Abu Ubayd al-Juzjani, a pupil of Ibn Sīnā, claimed that his teacher Ibn
Sīnā had solved the equant problem in Ptolemy's planetary
model.[20]
Chemistry
In chemistry, steam distillation was invented
by Ibn Sīnā in the early 11th century, which he used to produce essential oils.[19]
Earth sciences
Ibn Sīnā wrote on the earth sciences in The
Book of Healing. In geology, he hypothesized two causes of mountains:
"Either they are the effects of upheavals of the crust of the earth, such as might occur during a violent earthquake, or
they are the effect of water, which, cutting itself a new route, has
denuded the valleys, the strata being of different kinds, some
soft, some hard... It would require a long period of time for all such changes to be accomplished, during which the mountains
themselves might be somewhat diminished in size."[21]
Physics
In physics, Ibn Sīnā was the first to employ an air thermometer to measure air temperature in his scientific
experiments.[22]
In mechanics, Ibn Sīnā developed an elaborate theory of motion, in which he made a distinction between the inclination and
force of a projectile, and concluded that motion was a result
of an inclination (mayl) transferred to the projectile by the thrower, and that projectile
motion in a vacuum would not cease.[23] He viewed inclination as a permanent force whose effect is dissipated by external forces such
as air resistance.[24] His theory of motion was thus consistent with the concept of inertia in Newton's first law of motion.[23] Ibn Sīnā also referred to mayl to as
being proportional to weight times velocity, a precursor to the
concept of momentum in Newton's second law of
motion.[25] Ibn Sīnā's theory of mayl was
further developed by Jean Buridan in his theory of impetus.
In optics, Ibn Sina discovered that the speed of light
is finite, as he "observed that if the perception of light is due to the emission of some sort of
particles by a luminous source, the speed of light must be finite."[26] He also provided a sophisticated explanation for the
rainbow phenomenon. Carl Benjamin Boyer
described Ibn Sīnā's theory on the rainbow as follows:
"Independent observation had demonstrated to him that the bow is not formed in the dark cloud but rather in the very thin mist
lying between the cloud and the sun or observer. The cloud, he thought, serves simply as the background of this thin substance,
much as a quicksilver lining is placed upon the rear surface of the glass in a mirror. Ibn Sīnā would change the place not only
of the bow, but also of the color formation, holding the iridescence to be merely a subjective sensation in the eye."[27]
Philosophy
Ibn Sīnā wrote extensively on the subjects of philosophy, logic, ethics, metaphysics and other
disciplines. Most of his works were written in Arabic - which was the de facto
scientific language of that time, and some were written in the Persian language. Of linguistic significance even to this day are a few books that he wrote in nearly
pure Persian language (particularly the Danishnamah-yi 'Ala', Philosophy for Ala' ad-Dawla'). Ibn Sīnā's commentaries on
Aristotle often corrected the philosopher, encouraging a lively debate in the spirit of ijtihad.
Ibn Sīnā's philosophical tenets have become of great interest to critical Western scholarship and to those engaged in the
field of Muslim philosophy, in both the West and the East. However, it is still the case that the West only pays attention to a
portion of his philosophy known as the Latin Avicennian School. Ibn Sīnā's philosophical contributions have been
overshadowed by Orientalist scholarship (for example that of Henri Corbin), which has
sought to define him as a mystic rather than an Aristotelian philosopher. The so-called
حكمت مشرقيه (hikmat-al-mashriqqiyya) remains a source of huge irritation to contemporary Arabic scholars, in
particular Reisman, Gutas, Street, and Bertolacci.
The original work, entitled The Easterners (al-mashriqiyun), was probably lost during Ibn Sīnā's lifetime;
Ibn Tufayl appended it to a romantic philosophical work of his own in the twelfth century,
the Hayy ibn Yaqzan, in order to validate his philosophical system, and, by the
time that the work was transmitted into the West, appended as it was to a set of "mystical" opusculae and sundry essays, it was
firmly accepted as a demonstration of Ibn Sīnā's "esoteric" orientation, which he concealed out of necessity from his peers.
Some argue that such interpretations of Ibn Sīnā's "true" state of mind ignore the vast corpus of work that he produced, from
major treatises to slurs on his enemies and rivals, misrepresent him utterly. It also detracts attention from the fact that
Muslim philosophy flourished during the ten centuries after Ibn Sīnā's death, emerging from Ibn Sīnā's inflammatory
pronouncements on all matters within the world, whether physical or metaphysical; the works of the post-Avicennian Baghdadi
Peripatetics and anti-Peripatetics, for example, remain to be studied in much greater detail.
Metaphysical doctrine
Islamic philosophy, imbued as it is with theology, distinguishes more clearly than Aristotelianism the difference between
essence and existence. Whereas existence is the domain of the
contingent and the accidental, essence endures within a being beyond the accidental. However, Ibn Sīnā's commentaries upon the
Metaphysics in particular demonstrate that he was much more clearly aligned with a philosophical comprehension of the
metaphysical world rather than one that was grounded in theology. (See, for example, the Compendium on the Soul, where beneath
the heading of Metaphysics he prioritises Universal Science (Being-as-such and First Philosophy) over theology.) The philosophy
of Ibn Sīnā, particularly that part relating to metaphysics, owes much to Aristotle and to Al-Farabi. The search for a truly definitive Islamic
philosophy can be seen in what is left to us of his work.
God as the first cause of all things
For Ibn Sīnā, essence is non-contingent. For an essence to be realised within time (as an existence), the existence must be
rendered necessary by the essence itself. This particular relationship of cause and
effect is due to an inherent property of the essence, that it is non-contingent. For existence in general to be possible,
there must exist a necessary essence, itself uncaused - a being or God to begin a process of emanation.
This view has a profound impact on the monotheistic concept of creation. Existence is not
seen by Ibn Sīnā as the work of a capricious deity, but of a divine, self-causing thought process. The movement from this to
existence is necessary, and not an act of will per se. The world emanates from God by virtue of his abundant intellect - an
immaterial cause as found in the neoplatonic concept of emanation.
Ibn Sīnā found inspiration for this methaphysical view in the works of Al-Farabi, but his
innovation is in his account a single and necessary first cause of all existence. Whether this view can be reconciled with
Islam, particularly given the question of what role is left for God's will, was to become a
subject of considerable controversy within intellectual Islamic discourse.
The Ten Intellects
In Ibn Sīnā's account of creation (largely derived from Al-Farabi), from this first cause
(or First Intellect) proceeds the creation of the material world.
The First Intellect, in contemplating the necessity of its existence, gives rise to the Second Intellect. In contemplating its
emanation from God, it then gives rise to the First Spirit, which animates the Sphere of Spheres (the universe). In contemplating
itself as a self-caused essence (that is, as something that could potentially exist), it gives rise to the matter that fills the
universe and forms the Sphere of the Planets (the First Heaven in al-Farabi).
This triple-contemplation establishes the first stages of existence. It continues, giving rise to consequential intellects
which create between them two celestial hierarchies: the Superior Hierarchy of
Cherubim (Kerubim) and the Inferior Hierarchy, called by Ibn Sīnā "Angels of Magnificence". These angels animate the heavens, but are deprived of all sensory
perception, but have imagination which allows them to desire the intellect from which they came. Their vain quest to join this
intellect causes an eternal movement in heaven. They also cause prophetic visions in humans.
The angels created by each of the next seven Intellects are associated with a different body in the Sphere of the Planets.
These are: Saturn, Jupiter, Mars, the Sun, Venus, Mercury and the Moon. The last of these is of particular importance,
since its association is with the Angel Gabriel ("The Angel").
This Ninth Intellect occurs at a step so removed from the First Intellect that the emanation that then arises from it explodes
into fragments, creating not a further celestial entity, but instead creating human souls, which have the sensory functions
lacked by the Angels of Magnificence.
The Angel and the minds of humans
For Ibn Sīnā, human minds were not in themselves formed for abstract thought. Humans are intellectual only potentially, and
only illumination by the Angel confers upon them the ability to make from this potential a real ability to think. This is the
Tenth Intellect, identified with the "active intellect" of Aristotle's De Anima.
The degree to which minds are illuminated by the Angel varies. Prophets are illuminated to
the point that they posses not only rational intellect, but also an imagination and ability which allows them to pass on their
superior wisdom to others. Some receive less, but enough to write, teach, pass laws, and contribute to the distribution of
knowledge. Others receive enough for their own personal realisation, and others still receive less.
On this view, all humanity shares a single agent intellect - a collective consciousness. The final stage of human life,
according to Ibn Sīnā, is reunion with the emanation of the Angel. Thus, the Angel confers upon those imbued with its intellect
the certainty of life after death. For Ibn Sīnā, as for the neoplatonists who influenced
him, the immortality of the soul is a consequence of its nature, and not a purpose for it to fulfill.
Criticism
Ibn Sīnā's heterodox beliefs, namely his belief that bodily resurrection was impossible,
placed him at odds with traditionalist Muslim scholars of his time. This departure from
orthodox thought led the prominent Ash'ari scholar al-Ghazzali to consider Ibn Sīnā a disbeliever of Islam, and he argued that it was fard to consider him a Kafir.[28]
Logic
The first criticisms on Aristotelian logic were written by Ibn Sina, who produced independent
treatises on logic rather than commentaries. He criticized the logical school of Baghdad for their devotion to Aristotle at the time. He investigated the
theory of definition and classification and
the quantification of the predicates of
categorical propositions, and developed an original theory on "temporally modalized"
syllogism. Its premises included modifiers such as "at all
times", "at most times", and "at some time".[29]
Natural philosophy
Ibn Sina and Abū Rayhān al-Bīrūnī, who are both regarded as two of the greatest
polymaths in Persian history, engaged in a written debate, with al-Biruni mostly criticizing
Aristotelian natural philosophy and the
Peripatetic school, while Avicenna and his student Ahmad ibn 'Ali al-Ma'sumi respond
to al-Biruni's criticisms in writing. Al-Biruni began by asking Avicenna eighteen questions, ten of which were criticisms of
Aristotle's On the Heavens. After Avicenna
responded to the questions, al-Biruni was unsatisfied with some of the answers and wrote back commenting on them, after which
Avicenna's student Ahmad ibn 'Ali al-Ma'sumi wrote back on behalf of Avicenna.[30]
Engineering
In the chapters on mechanics and engineering in his
encyclopedia Mi'yar al-'aql (The Measure of the Mind), Avicenna writes an analysis on the ilm al-hiyal
(science of ingenious devices) and makes the first successful attempt to classify simple machines and their combinations. He first describes and illustrates the
five constituent simple machines: the lever, pulley, screw, wedge, and windlass. He then analyzes all the combinations
of these simple machines, such as the windlass-screw, windlass-pulley and windlass-lever for example. He is also the first to
describe a mechanism which is essentially a combination of all of these simple
machines (except for the wedge).[31]
Poetry
Almost half of Ibn Sīnā's works are versified.[32] His
poems appear in both Arabic and Persian. As an example, Edward Granville Browne
claims that the following verses are incorrectly attributed to Omar Khayyám, and were
originally written by Ibn Sīnā [33]:
از قعر گل سیاه تا اوج زحل,
Up from Earth's Centre through the Seventh Gate
کردم همه مشکلات گیتی را حل,
I rose, and on the Throne of Saturn sate,
بیرون جستم زقید هر مکر و حیل,
And many Knots unravel'd by the Road;
هر بند گشاده شد مگر بند اجل.
But not the Master-Knot of Human Fate.
Legacy
Ibn Sīnā commemorated on a
Polish stamp
George Sarton, the father of the history of science, described Ibn Sīnā as "one of the
greatest thinkers and medical scholars in history"[9] and called him "the most famous scientist of Islam and
one of the most famous of all races, places, and times." He was one of the Islamic
world's leading writers in the field of medicine. He was influenced by the approach of Hippocrates and Galen, as well as