Athir al-Din al-Abhari

Works

• c. 1250Guide to Philosophy

  Handbook of the whole of philosophy in three parts – logic, physics and metaphysics – largely following Ibn Sina; through its commentaries, above all Mulla Sadra’s, it carried Avicennan philosophy into the madrasas of Iran, the Ottoman lands and India.

• c. 1250Introduction to Logic (Isagoge)

  Short introduction to logic, named after Porphyry’s Isagoge: the five universals, definition, propositions, syllogism and the kinds of argument in a few pages; it became the first logic text of madrasa students for centuries, was commented on many times and appeared in a Latin translation in 1625.

Position

Al-Abhari is on the map as one of the logicians through whom Ibn Sina’s philosophy became the curriculum of the madrasas. His short Isagoge – named after Porphyry’s introduction, but covering the whole of logic in a few pages – was for centuries the first logic text that students read, from the Ottoman lands to India, and his Guide to Philosophy (Hidāyat al-ḥikma) presented logic, physics and metaphysics in one handbook whose metaphysics follows Ibn Sina closely. In his longer works on logic he belonged to the thirteenth-century logicians who revised Ibn Sina. Examining Afdal al-Din al-Khunaji’s reading of propositions according to the essence of their subject, he showed that it would make all universal propositions false and all particular ones true; he therefore restricted that reading to what is possible and added the “mental proposition”, whose subject exists in the mind. Unlike Ibn Sina, he admitted that impossible things can exist in the mind. Al-Katibi and many later logicians adopted this framework. Nasir al-Din al-Tusi answered al-Abhari’s logic in a systematic critique, Adjusting the Standard (Taʿdīl al-miʿyār), one of the main confrontations between defenders of Ibn Sina’s logic and its revisers. Al-Abhari also took up Suhrawardi’s criticism of the distinction between essence and existence. Through the commentaries on his Guide to Philosophy his influence lasted into modern times: Mulla Sadra’s commentary became, in Sajjad Rizvi’s words, the cornerstone of the rationalist curriculum of the Indian madrasa from the eighteenth century.

Life & context

Athir al-Din al-Mufaddal ibn ʿUmar al-Abhari was born in Abhar, a small town between Qazvin and Zanjan in north-western Iran; his year of birth is unknown, and Wikidata gives 1194. Later reports make him a student of Fakhr al-Din al-Razi, but modern scholars doubt that the two ever met. When the Mongols overran the Khwarazmian empire he moved west: by 1228 he was in Erbil, and he studied in Damascus and in Mosul, where he learned mathematics and astronomy from Kamal al-Din ibn Yunus. He taught logic, philosophy and astronomy; among his students were the logician Najm al-Din al-Katibi, the cosmographer Zakariya al-Qazwini and the biographer Ibn Khallikan. Besides his works on logic and philosophy he wrote on astronomy and on Euclid, including an attempt to prove the parallel postulate. He died between 1262 and 1265, according to most accounts in Mosul.

Further main works

• Introduction to Logic (Īsāghūjī)
• Tanzīl al-afkār fī taʿdīl al-asrār, on logic (criticised by Nasir al-Din al-Tusi)
• Kashf al-ḥaqāʾiq fī taḥrīr al-daqāʾiq, on logic, physics and metaphysics
• Treatises on astronomy and on Euclid