Abū al-Qāsim al-Balkhī, ʿAbd Allāh b. Aḥmad b. Maḥmūd (d. 319/931), was a well-known Muʿtazilī theologian from Baghdad. He was also known as al-Kaʿbī, deriving from the name of one of his forebears, Kaʿb (al-Samʿānī, 11/122).

Abū al-Qāsim was apparently born in Balkh. This can be deduced from the comments of some authorities, including al-Khaṭīb al-Baghdādī (9/384), that he returned to Balkh after completing his education and living some time in Baghdad (see also Ibn…