Ibn Sina was born in year 370 of the Hegira (year 980 of the Christian era) in Khurasan, which along with Baghdad was the most important centre of intellectual activity in the Islamic world during the fourth century (tenth century). By the time he had opened his eyes to this world, such philosophers as al-Kindi, al-Farabi, Abu'I-J::Iasan al-'Amin, and Abu Sulayman al-Sijistani had already established the foundations of Peripatetic (mashshii l) philosophy in Islam. The Mu 'tazilite school had already produced its most illustrious representatives such as al-Na~~am and Abu'l-Hudhayl al-' Allaf. The Ash 'arites, through Abu'I-J::Iasan aI-Ash 'an and Abu Bakr al-BaqillanI, had capfitured the centre of the intellectual arena in Baghdad as far as Kaiiim was concerned, and were pressing their attacks against the falsafah. Other schools of Islamic philosophy such as the Hermetico-Pythagorean and the Isma'ill had produced important figures such as Jabir ibn J::Iayyan and Abu Ya 'qub al-SijisHini. Sufism of both the Baghdadi and Khurasani schools had been witness to the lives and teachings of such outstanding masters as Junayd, J::Iallaj and Bayazld. Likewise, Islamic science had already produced some of its outstanding luminaries such as MUQammad ibn Musa al-Khwarazmi in mathematics and MUQammad ibn Zakariyya' Razi (Rbazes) in medicine.