of Abu Hanifa, Abu Yusuf's doctrine largely presupposes that of his mentor. His writings and prominent political positions helped advance the Hanafi school of Islamic law throughout the Islamic empire. While most of his legal opinions (fatwas) were firmly rooted in the doctrine and methodology espoused by his former teacher, there are some points on which he diverged and revealed his own legal thought. Abu Yusuf's greatest legacy is in affirming and advancing the Hanafi legal school as the predominant source of legal thought in the Islamic empire and providing a legal framework for defining and restricting caliphal authority in regard to fiscal policy. List of works Kitab al-Kharaj, his most famous work, is a treatise on taxation and fiscal problems of the state prepared for the caliph. Usul al-fiqh - the earliest known work of principles of Islamic jurisprudence. A portion of his works were devoted to international law. Kitab ul-Aathar, a collection of traditions (ahadith) he narrated. Kitab Ikhtilaf Abi Hanifa wa Ibn Abi Layla, one of the early works on comparative fiqh Kitab al-Radd ‘Ala Siyar al-Awza’i, a refutation of the famous Syrian jurist and tradition, al-Awza’i on the law of war. These 3 books were published by Al Ihya Al Ma'arif an N'omaniya under the guidance of Abul Wafa Al Afghani Early Islam scholars See also Islamic scholars Muhammad al-Shaybani Sharia List of Islamic scholars described as father or founder of a field References Year of birth unknown 798 deaths Hanafi fiqh scholars Sunni Muslim scholars of Islam 8th-century Muslim scholars of Islam 8th-century people from the Umayyad Caliphate Chief qadis of the Abbasid Caliphate 8th-century people from the Abbasid Caliphate One Thousand and One Nights characters 8th-century jurists 8th-century Arabs Taba‘ at-Tabi‘in hadith narrators