The treatise preserved in this manuscript, Al-Luma‘al-yasīra fī ‘ilm al-hisāb (The little sparkles on the science of calculation), deals with Muslim inheritance. Of the social innovations that came with the Islamic conquest, the introduction of the system of fara'id (shares) for inheritances was one of the most radical and socially advanced. The fourth surah of the Qur'an, verses 11–12, criticizes the traditional pre-Islamic system of agnatic succession, under which only men could inherit property, and provides for a proportional division among all the heirs, women included. The exact reckoning of the shares of inheritance became a delicate and complex subject within Islamic law, and Muslim intellectuals devised mathematical tools to simplify the calculations implied in the ‘ilm al-fara'id (the science of the shares). This work, written in the last years of the 14th century, is a contribution on this subject by Aḥmad ibn Muḥammad ibn al-Ha’im (1356–1412). The treatise is not confined to problems of inheritance: Ibn al-Ha’im introduces his arguments with extensive passages on numbers, their types and different features, and devotes most of the work to discussing multiplication (darb) and division (qisma).