Abū al-Ḥasan al-Bisyawī, ʿAlī b. Muḥammad b. ʿAlī, was an Ibāḍī scholar who lived in the 4th/10th century in Oman. His nisba ‘al-Bisyāwī’ or ‘al-Bisyānī’ refers to Bisyā, one of the regions of Bahlā in Oman (al-ʿIbrī, 3). Neither the date of his birth nor the date of his death is given in the sources. However, it can be reckoned that he was born in the second quarter of the 4th/10th century, and that he died in the first quarter of the 5th/11th century. His father, Muḥammad b. ʿAlī, w…