ABŪ YŪSUF (ah 113–182/731–798 ce), more fully Yaʿqūb ibn Ibrāhīm al-Anṣārī al-Kūfī; Islamic jurisconsult and, with Muhammad ibn Hasan al-Shāybanī (d. ah 189/805 ce), one of the founders of the Ḥanafī school of law. Abū Yūsuf flourished at a time of transition, when legal doctrine was still being formulated independently of the practice of the courts by groups of idealistic religious scholars in geographically determined schools. At the same time, individual scholars were appointed qāḍī s, or judges, by the government, especially under the Abbasids, who fostered a policy of official support for the religious law. The period also coincided with the beginning of the literary expression of technical legal thought. Abū Yūsuf's life and doctrines may be seen in the context of all these developments.
As a student and disciple of Abū Ḥanīfah, Abū Yūsuf is identified primarily with the tradition of Kufa in religious law and traditions. Born in Kufa, he was of Medinese ancestry. He is known to have studied with Mālik ibn Anas in Medina and others, but tradition states that Abū Ḥanīfah recognized the moral and intellectual excellence of the penniless young man and took him under his wing. Abū Yūsuf lived in Kufa as a practicing judge until he was appointed qāḍī of the capital (Baghdad), or chief judge, as his honorific (qāḍī al-quḍāt ) indicates, by the Abbasid caliph, Hārūn al-Rashīd. The first to receive this title, Abū Yūsuf was not only consulted on the appointment and dismissal of the judiciary throughout the empire but acted as counselor to the caliph on legal and administrative matters and on financial policy. His chief extant work, the Kitāb al-kharāj, a treatise on taxation, public finance, and penal law, was written at the caliph's request and contains a long introduction addressed to him.
A number of works on religious law, most of which are either reasoned polemics or comparative studies of the doctrines of his contemporaries, are attributed to Abū Yūsuf, but few of these have survived. Abū Yūsuf's own doctrine can be seen within the framework of the developing technical legal thought of the Iraqi scholars, who lived in a more heterogeneous milieu and were inspired by a freer method of inquiry than that followed by the more tradition-bound Medinese. However, Abū Yūsuf tended to rely more on ḥadīth as the basis for legal rulings than had Abū Ḥanīfah, probably because a larger number of authoritative traditions from the Prophet had come into existence by Abū Yūsuf's time. Further, where Abū Ḥanīfah could proceed along lines of theoretical speculation and systematic consistency, Abū Yūsuf's experience as a practicing qāḍī caused him to mitigate his master's formalism, if often at the expense of his master's superior reasoning. In contrast to al-Shaybānī, an academic lawyer, prolific writer, and the systematizer of the school of Kufa, Abū Yūsuf was a man of affairs who made his influence felt in court circles. Since Abū Ḥanīfah himself left no writings on law, it was through the activity of these two men that the ancient school of Kufa was to become the Ḥanafī school of law.
Abū Yūsuf's Kitāb al-kharāj has been translated into French by Edmond Fagnan as Le livre de l'impôt foncier (Paris, 1927), and partially into English by Aharon Ben Shemesh as Abū Yūsuf's Kitāb al-kharāj (Leiden, 1969). Ben Shemesh's translation omits the sections dealing with history, criminal justice, and administration and rearranges the order of the sections of the text on taxation; on the whole it is not so lucid a translation as Fagnan's. A systematic study of Abū Yūsuf's thought and his role in the creation of Islamic law is given by Joseph Schacht in his pathbreaking Origins of Muhammadan Jurisprudence (Oxford, 1950). For the historical context, see Schacht's An Introduction to Islamic Law (Oxford, 1964).
Jeanette A. Wakin (1987)