'Athir al-Din Mufaddal ibn Umar al-Abhari' (1200 - 1265), was a Persian philosopher and mathematician.

He wrote The Kitab at-Hiddyah dealing with a complete cycle of Hikmat, i.e., logic, natural philosophy, and metaphysics.

His work on logic has been entitled as al-Isaghuji.

He also made notable contributions to theoretical geometry.

His works were translated into Hebrew and Latin and his influence is evident in Wetsern treatises of late medieval and Renaissanc times.

See also

• List of Iranian scientists