Ibn Kammuna

Sa'd ibn Mansur (Izz Al-dawla) Ibn Kammuna (, 1215—1284, was a 13th-century Jewish physician and philosopher. His main works include a comparative treatise of the three Abrahamic religions, which includes a well informed critical evaluation of Islam, as well as a commentaries on Ibn Sina and as-Suhrawardi.

Works

Ibn Kammuna's commentary on Shahab al-Din Suhrawardi's Talwihat, the core text of Illuminationist philosophy is deemed as one of the most thorough examination of that branch of thought.

His comparative treatise on the three monotheistic religions Christianity, Judaism and Islam, titled Examination of the Three Faiths challenged the legitimacy of Islam where he reasoned that incompatibility of sharia with the principles of justice undercuts Muhammad's claims of being a perfect man and stated that people convert to Islam from ulterior motives.

"That is why, to this day we never see anyone converting to Islam unless in terror, or in quest of power, or to avoid heavy taxation, or to escape humiliation, or if taken prisoner, or because of infatuation with a Muslim woman, or for some similar reason. Nor do we see a respected, wealthy, and pious non-Muslim well versed in both his faith and that of Islam, going over to the Islamic faith without some of the aforementioned or similar motives."

He goes on to regard Muhammad as unoriginal and imperfect. "We will not concede that Muhammad added to the knowledge of God and of obedience to him anything more than what was found in the earlier religions."

"There is no proof that Muhammad attained perfection and the ability to perfect others as claimed." Some scholars believe that Ibn Kammuna converted to Islam, claiming a possible conversion to Twelver Shiism in the last months of his life, as suggested by the author of Matalib.