Abà « Muḥammad al-Ḥasan ibn Aḥmad ibn Mattawayh () was a Muÿtazilë theologian and philosopher of the Bahshamë school. His dates of birth and death are unknown. He studied in Ray under QÃÂá¸Âë ÿAbd al-JabbÃÂr, who died in 1025. He is not associated with any place other than Ray. He may be the Muÿtazilë theologian called Sibá¹ Mattà «ya who is mocked in a poem by ÿAbd al-JabbÃÂr's patron, the vizier al-á¹¢ÃÂḥib ibn ÿAbbÃÂd, who died in 995. His datable writings were written not long after ÿAbd al-JabbÃÂr's death.
Ibn Mattawayh's two surviving works are:
In addition, two lost works by Ibn Mattawayh are known. His KitÃÂb al-KifÃÂya, quoted by Ibn Abiþl-Ḥadëd, argues for the ÿiá¹£ma (impeccability) of ÿAlë and his superiority over Abà « Bakr, but stops short of affirming the Shëÿë doctrine of the imÃÂmate. His KitÃÂb al-Taḥrër is quoted by Maḥmà «d ibn al-MalÃÂḥimë.
There is an anonymous commentary on Ibn Mattawayh's Tadhkira. The surviving manuscript copy indicates that the commentary was completed in 1175. The commentary, which is untitled, is much longer than the original work.