"Avicenna" is the Latinate form of Ibn Sīnā. For the mountain peak known by this name, see Ibn Sīnā Peak. Avicenna (/ˌævᵻˈsɛnə/; Latinized form of Ibn-Sīnā, Arabic full name Abū ʿAlī al-Ḥusayn ibn ʿAbd Allāh ibn Al-Hasan ibn Ali ibn Sīnā أبو علي الحسين ابن عبد الله ابن سينا; c. 980 – June 1037) was a Persian polymath who is regarded as one of the most significant thinkers and writers of the Islamic Golden Age. Of the 450 works he is known to have written, around 240 have survived, including 150 on philosophy and 40 on medicine. His most famous works are The Book of Healing. a philosophical and scientific encyclopedia, and The Canon of Medicine – a medical encyclopedia which became a standard medical text at many medieval universities and remained in use as late as 1650. In 1973, Avicenna's Canon Of Medicine was reprinted in New York. Besides philosophy and medicine, Avicenna's corpus includes writings on astronomy, alchemy, geography and geology, psychology, Islamic theology, logic, mathematics, physics and poetry.
Avicenna was born c. 980 in Afšana, a village near Bukhara (in present-day Uzbekistan), the capital of the Samanids, a Persian dynasty in Central Asia and Greater Khorasan. His mother, named Setareh, was from Bukhara; his father, Abdullah, was a respected Ismaili scholar from Balkh, an important town of the Samanid Empire, in what is today Balkh Province, Afghanistan, although this is not universally agreed upon. His father worked in the government of Samanid in the village Kharmasain, a Sunni regional power. After five years, his younger brother, Mahmoud, was born. Avicenna first began to learn the Quran and literature in such a way that when he was ten years old he had essentially learned all of them. A number of theories have been proposed regarding Avicenna's madhab (school of thought within Islamic jurisprudence). Medieval historian Ẓahīr al-dīn al-Bayhaqī (d. 1169) considered Avicenna to be a follower of the Brethren of Purity. On the other hand, Dimitri Gutas along with Aisha Khan and Jules J. Janssens demonstrated that Avicenna was a Sunni Hanafi. However, the 14th cenutry Shia faqih Nurullah Shushtari according to Seyyed Hossein Nasr, maintained that he was most likely a Twelver Shia. Conversely, Sharaf Khorasani, citing a rejection of an invitation of the Sunni Governor Sultan Mahmoud Ghazanavi by Avicenna to his court, believes that Avicenna was an Ismaili. Similar disagreements exist on the background of Avicenna's family, whereas some writers considered them Sunni, some more recent writers contested that they were Shia. According to his autobiography, Avicenna had memorised the entire Quran by the age of 10. He learned Indian arithmetic from an Indian greengrocer, Mahmoud Massahi and he began to learn more from a wandering scholar who gained a livelihood by curing the sick and teaching the young. He also studied Fiqh (Islamic jurisprudence) under the Sunni Hanafi scholar Ismail al-Zahid. Avicenna taught some extent of philosophy books such as Introduction (Isagoge)'s Porphyry (philosopher), Euclid's Elements, Ptolemy's Almagest by an unpopular philosopher, Abu Abdullah Nateli, who claimed philosophizing. As a teenager, he was greatly troubled by the Metaphysics of Aristotle, which he could not understand until he read al-Farabi's commentary on the work. For the next year and a half, he 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, made with the 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 of the sick had, according to his own account, discovered new methods of treatment. The teenager achieved full status as a qualified 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. He was a truly Renaissance man and polymath, the Leonardo da Vinci equivalent in the Arabic world.