From "Abu Ali al-Husayn ibn Sina [Avicenna], The Ideal Muslim Intellectual (eleventh century)," in Gettleman and Schaar, The Middle East and Islamic World Reader. Original source: A.J. Arberry, "Avicenna: His Life and Times" in G.M. Wickens, ed., Avicenna: Scientist and Philosopher (London: Luzac & Company, 1952), pp. 9 and 11-17:
When the Abbasid empire broke into small competing states, brilliant intellectuals such as Abu Ali al-Husayn ibn Sina (980-1037) found many rulers willing to patronize their scholarship. The political instability resulting from the weakening of Abbasid authority did not stifle the tradition of cultural and intellectual exchange among Islamic cities and centers of learning. Born in a village near the Central Asian city of Bukhara, ibn Sina continuously traveled in search of knowledge and work. In the course of his voyages he distinguished himself as one of the most famous physicians, intellectuals, and men of science in the world, and Europeans continued to teach from his celebrated writings on medicine up to the eighteenth century. Not only did he master the many texts of ancient thinkers in Arabic translations, but he also added to knowledge in the fields of law, theology, philosophy, optics, astronomy, medicine, poetry, and philology.
[The following selection is from ibn Sina's autobiography]:
By the time I was ten I had mastered the Koran and a great deal of literature, so that I was marveled at for my aptitude.
(My father and my brother would discuss theology) while I listened and comprehended all they said; but my spirit would not assent to their argument...[T]hey began to invite me to join...rolling on their tongues talk about philosophy, geometry, Indian arithmetic; and my father sent me to a certain vegetable seller who used the Indian arithmetic [and algebra], so that I might learn it from him.
Then there came to Bukhara a man called Abu Abd Allah al-Natili who claimed to be a philosopher; my father invited him to stay in our house, hoping that I would learn from him also. Before his advent [arrival] I had already occupied myself with Muslim jurisprudence, attending [studying with] Isma'il the Ascetic; so I was an excellent inquirer, having become familiar with the methods of postulation and the techniques of rebuttal according to the usages of the canon lawyers. ...He marveled at me exceedingly, and warned my father that I should not engage in any other occupation but learning; whatever problem he stated to me, I showed a better mental conception of it than he. So I continued until I had read the straightforward parts of [Aristotle's] Logic with him; as for the subtler points, he had no acquaintance with them.
From then onward I took to reading texts by myself; I studied the commentators until I had...mastered...Logic. Similarly with Euclid['s Elements of Geometry] I read the first five or six figures with him; and thereafter undertook on my own account to solve the entire remainder of the book.
I now occupied myself with mastering the various texts and commentaries on natural sciences and metaphysics, until all the gates of knowledge were open to me. Next I desired to study medicine, and...[proceeded] to read all the books that had been written on this subject. Medicine is not a difficult science, and naturally I excelled in it in a very short time, so that qualified physicians began to read medicine with me.