Ibn Sina ( – 22 June 1037), commonly known in the West as Avicenna, was a preeminent philosopher and physician of the Muslim world. He was a seminal figure of the Islamic Golden Age, serving in the courts of various Iranian rulers,*.(page 113) "For one thing, it means that he[Avicenna] had a Persian cultural background...he spoke Persian natively and did use it to write philosophy."(page 117) "But for the time being, it was a Persian from Khurasan who would have commentaries lavished upon him. Avicenna would be known by the honorific of "leading master" (al-shaykh al-raʾis)."(page 206) "Persians like Avicenna" . "Avicenna was a Persian whose father served the Samanids of Khurasan and Transoxania as the administrator of a rural district outside Bukhara."

. "He was born in 370/980 in Afshana, his mother's home, near Bukhara. His native language was Persian." "Avicenna was the greatest of all Persian thinkers; as physician and metaphysician ..." (excerpt from A.J. Arberry, Avicenna on Theology, Kazi Publications Inc, 1995). . "Whereas the name of Avicenna (Ibn Sina, died 1037) is generally listed as chronologically first among noteworthy Iranian philosophers, recent evidence has revealed previous existence of Ismaili philosophical systems with a structure no less complete than of Avicenna." and was influential to medieval European medical and Scholastic thought. Avicenna is considered one of the greatest thinkers and medical scholars in history.

Often described as the father of early modern medicine, Avicenna's most famous works are The Book of Healing, a philosophical and scientific encyclopedia, and The Canon of Medicine, a medical encyclopediaEdwin Clarke, Charles Donald O'Malley (1996), The human brain and spinal cord: a historical study illustrated by writings from antiquity to the twentieth century, Norman Publishing, p. 20 ().Iris Bruijn (2009), Ship's Surgeons of the Dutch East India Company: Commerce and the progress of medicine in the eighteenth century, Amsterdam University Press, p. 26 (). that became a standard medical text at many medieval European universities and remained in use as late as 1650.e.g. at the universities of Montpellier and Leuven (see ).

Besides philosophy and medicine, Avicenna's corpus includes writings on astronomy, alchemy, geography and geology, psychology, Islamic theology, logic, mathematics, physics, and works of poetry. His philosophy was of the Peripatetic school derived from Aristotelianism, of which he is considered among the greatest proponents within the Muslim world.

Avicenna wrote most of his philosophical and scientific works in Arabic but also wrote several key works in Persian; his poetry was written in both languages. Of the 450 works he is believed to have written, around 240 have survived, including 150 on philosophy and 40 on medicine.

Avicenna is also known for his unique methodological approach to his works. He combines a unique blend of empirical observation, philosophical reasoning, and logical analysis, in order to conduct his analysis and reach his conclusions. This is especially the case in his medical works, namely The Canon of Medicine.

Name is a Latinized version of the Arabic patronym ibn Sīnā (),. indicating that he is the descendant of a line of men going back to one named Sina. Specifically, Avicenna was the great-great-grandson of a Sina. His full formal Arabic name is Abū ʿAlī al-Ḥusayn bin ʿAbdallāh bin al-Ḥasan bin ʿAlī bin Sīnā al-Balkhī al-Bukhārī ().

Historical context Avicenna created an extensive corpus of works during what is commonly known as the Islamic Golden Age, in which the translations of Byzantine, Greco-Roman, Persian, and Indian texts were studied extensively. Greco-Roman (Middle Platonic, Neoplatonic, and Aristotelian) texts translated by the Kindi school were commented on, redacted and developed substantially by Islamic intellectuals, who also built upon Persian and Indian mathematical systems, astronomy, algebra, trigonometry and medicine.

The Samanid Empire in the eastern part of Persia, Greater Khorasan, and Central Asia, as well as the Buyid dynasty in the western part of Persia and Iraq, provided a thriving atmosphere for scholarly and cultural development. Under the Samanids, Bukhara rivaled Baghdad for cultural capital of the Muslim world. There, Avicenna had access to the great libraries of Balkh, Khwarazm, Gorgan, Rey, Isfahan and Hamadan.

Various texts (such as the 'Ahd with Bahmanyar) show that Avicenna debated philosophical points with the greatest scholars of the time. Nizami Aruzi described how before ibn Sina left Khwarazm, he had met al-Biruni (a scientist and astronomer), Abu Nasr Mansur (a renowned mathematician), Abu Sahl 'Isa ibn Yahya al-Masihi (a respected philosopher) and ibn al-Khammar (a great physician). The study of the Quran and the Hadith also thrived, and Islamic philosophy, fiqh "jurisprudence", and kalam "speculative theology" were all further developed by ibn Sina and his opponents at this time.

Biography Early life and education Avicenna was born in in the village of Afshana in Transoxiana to a Persian family.According to , Avicenna was "of Persian descent". According to , Avicenna was "born of Persian parentage". According to , Avicenna was "Persian by birth". , mentions Avicenna as an example for "Persian-born authors" and speaks of "presumed Persian origins" for Avicenna. , states "An ethnic Persian, he [Avicenna] was born in Kharmaithen, near Bukhara". The village was near the Samanid capital of Bukhara, which was his mother's hometown. His father Abd Allah was a native of the city of Balkh in Bactria. An official of the Samanid bureaucracy, the father had served as the governor of a village of the royal estate of Harmaytan near Bukhara during the reign of Nuh II (). Avicenna also had a younger brother. A few years later, the family settled in Bukhara, a center of learning, which attracted many scholars. It was there that Avicenna was educated, which early on was seemingly administered by his father.

Although both Avicenna's father and brother had converted to Isma'ilism, he himself did not follow the faith. He was instead a Hanafi Sunni, the same school followed by the Samanids. Avicenna's parents recognized his brilliance from a very young age and hired tutors in Arabic language and Islamic knowledge to set him on the path towards intellectual thinking.

Avicenna was first schooled in the Quran and literature, and by the age of 10, he had memorized the entire Quran. He was later sent by his father to an Indian greengrocer, who taught him arithmetic. Afterwards, he was schooled in fiqh by the Hanafi jurist Ismail al-Zahid. Sometime later, his father invited the physician and philosopher al-Natili to their house to educate ibn Sina. Together, they studied the Isagoge of Porphyry (died 305) and possibly the Categories of Aristotle (died 322 BCE) as well. After Avicenna had read the Almagest of Ptolemy (died 170) and Euclid's Elements, al-Natili told him to continue his research independently. By the time Avicenna was 18, he was well-educated in Greek sciences. Although ibn Sina mentions only al-Natili as his teacher in his autobiography, he most likely had other teachers as well, such as the physicians Qumri and Abu Sahl 'Isa ibn Yahya al-Masihi.

Career In Bukhara and Gurganj

At the age of 17, Avicenna was made a physician of Nuh II. By the time Avicenna was at least 21 years old, his father died. He was subsequently given an administrative post, possibly succeeding his father as the governor of Harmaytan. Avicenna later moved to Gurganj, the capital of Khwarazm, which he reports that he did due to "necessity". The date he went to the place is uncertain, as he reports that he served the Khwarazmshah, the ruler of Khwarazm, the Ma'munid ruler Abu al-Hasan Ali. The latter ruled from 997 to 1009, which indicates that Avicenna moved sometime during that period.

He may have moved in 999, the year in which the Samanid Empire fell after the Kara-Khanid Khanate captured Bukhara and imprisoned the Samanid emir Abd al-Malik II. Due to his high position and strong connection with the Samanids, ibn Sina may have found himself in an unfavorable position after the fall of his suzerain.

It was through the minister of Gurganj, Abu'l-Husayn as-Sahi, a patron of Greek sciences, that Avicenna entered into the service of Abu al-Hasan Ali. Under the Ma'munids, Gurganj became a centre of learning, attracting many prominent figures, such as ibn Sina and his former teacher Abu Sahl al-Masihi, the mathematician Abu Nasr Mansur, the physician ibn al-Khammar, and the philologist al-Tha'alibi.

In Gorgan Avicenna later moved due to "necessity" once more (in 1012), this time to the west. There he travelled through the Khurasani cities of Nasa, Abivard, Tus, Samangan and Jajarm. He was planning to visit the ruler of the city of Gorgan, the Ziyarid Qabus (), a cultivated patron of writing, whose court attracted many distinguished poets and scholars. However, when Avicenna eventually arrived, he discovered that the ruler had been dead since the winter of 1013. Avicenna then left Gorgan for Dihistan, but returned after becoming ill. There he met Abu 'Ubayd al-Juzjani (died 1070) who became his pupil and companion. Avicenna stayed briefly in Gorgan, reportedly serving Qabus's son and successor Manuchihr () and resided in the house of a patron.

In Ray and Hamadan

In , Avicenna went to the city of Ray, where he entered into the service of the Buyid amir Majd al-Dawla () and his mother Sayyida Shirin, the de facto ruler of the realm. There he served as the physician at the court, treating Majd al-Dawla, who was suffering from melancholia. Avicenna reportedly later served as the "business manager" of Sayyida Shirin in Qazvin and Hamadan, though details regarding this tenure are unclear. During this period, Avicenna finished writing The Canon of Medicine and started writing his The Book of Healing.

In 1015, during Avicenna's stay in Hamadan, he participated in a public debate, as was customary for newly arrived scholars in western Iran at that time. The purpose of the debate was to examine one's reputation against a prominent resident. The person whom Avicenna debated against was Abu'l-Qasim al-Kirmani, a member of the school of philosophers of Baghdad. The debate became heated, resulting in ibn Sina accusing Abu'l-Qasim of lack of basic knowledge in logic, while Abu'l-Qasim accused ibn Sina of rudeness and impoliteness.

After the debate, Avicenna sent a letter to the Baghdad Peripatetics, asking if Abu'l-Qasim's claim that he shared the same opinion as them was true. Abu'l-Qasim later retaliated by writing a letter to an unknown person in which he made accusations so serious that ibn Sina wrote to Abu Sa'd, the deputy of Majd al-Dawla, to investigate the matter. The accusation made towards Avicenna may have been the same as he had received earlier, in which he was accused by the people of Hamadan of copying the stylistic structures of the Quran in his Sermons on Divine Unity. The seriousness of this charge, in the words of the historian Peter Adamson, "cannot be underestimated in the larger Muslim culture".

Not long afterwards, Avicenna shifted his allegiance to the rising Buyid amir Shams al-Dawla, the younger brother of Majd al-Dawla, which Adamson suggests was due to Abu'l-Qasim also working under Sayyida Shirin. Avicenna had been called upon by Shams al-Dawla to treat him, but after the latter's campaign in the same year against his former ally, the Annazid ruler Abu Shawk (), he forced Avicenna to become his vizier.