Ibn ‘Adi, Yahya

(279–363/893–974)

   A student of Matta ibn Yunus and al-Farabi, the Syrian Monophysite Jacobite Christian Yahya ibn ‘Adi was one of the most respected logicians and influential intellectuals in the fourth/tenth century. He founded the Aristotelian school in Baghdad, translated numerous Greek philosophical texts from Syriac to Arabic, and wrote a number of logical, philosophical and theological treatises. Among his more important works are The Reformation of Character (Tadhib al-akhlaq), an ethical work on the cultivation of virtue which takes as its starting point a Platonic model of the soul (this would serve as a template for Miskawayh’s book of the same title), and Essay on Unity (Maqala fi altawhid), in which he applies his considerable logical skills to defending the compatibility of God’s unity with the notion of the trinity (characterized as the three divine attributes of goodness, power and wisdom). He addresses al-Kindi on this point specifically in a separate work entitled Exposition of the Error of Abu Yusuf Ya‘qub ibn Ishaq al-Kindi in his Treatise ‘A Rebuttal of the Christians’ (Tabyin ghalat Abi Yusuf Ya‘qub ibn Ishaq al-Kindi fi maqalatiha fi al-Radd‘ala al-nasara). Yahya ibn ‘Adi was one of the few Christian philosophers who possessed an intellectual authority even among Muslims. Though not an influential figure in the long term, he was arguably the preeminent thinker of his day and represents a crucial link in the genealogy of classical Islamic philosophy. A number of his students went on to become eminent intellectual figures in their own right: al-Sijistani, al-Tawhidi and Miskawayh, as well as the Nestorian Christian Ibn al- Khammar and the Jacobite Christian Ibn Zur‘a.

   See ethics; al-Farabi; God, unity of; Miskawayh; al-Sijistani, Abu Sulayman Muhammad; al-Tawhidi

   Further reading: Ibn ‘Adi 2002; Kraemer 1986a/93, 1986b; Netton 1992/99