Husayn b. Qāsim

His kunya (teknonym) is Abū ʿAlī al-Ṭabarī. He is a Shāfiʿī faqīh (jurist). He is one of the imams who wrote on the subject of ikhtilāf (disagreement) and is also the first to produce a work on this matter. He authored works such as al-Iẓāḥ fī al-Madhhab, Kitāb fī al-Jadal, Uṣūl al-Fiqh, and similar writings. His biography is narrated in the book Ṭabaqāt.