The Greek-Arabic sciences penetrated in the Islamic world during the 8th and 9th centuries AD due to the massive activity of the translators and al-Kindi’s vision of knowledge and also through the exegetical activity of the Aristotelian circle of Baghdad. From the end of the 10th, throughout the 11th, and up to the beginning of the 12th centuries, the production of original philosophical literature into Arabic and Persian became the main stream of the Arabic-Islamic philosophy, which was by then increasingly distant from the Greek sources in Arabic translation. Avicenna’s works fully attest this phenomenon, which prompted a 12th century purist trend well exemplified in the Muslim West by Averroes’ program of going back to Aristotle: a similar phenomenon occurred also in the Muslim East, with Muwaffaq al-Din Muhammad ‘Abd al-Latif ibn Yusuf al-Baghdadi .