The eleventh century in Baghdad, cosmopolitan centre of culture of the Islamic world, is a Traditionalist century of great importance for the political and religious history of classical Islam, as well as for its institutional and intellectual history. In the political and religious realms, it brought the answer to the Mihna and the Rationalist policy of al-Ma'mun. The edicts and the creed of al-Qadir put their definitive Traditionalist imprint on Islam. In the institutional and intellectual realm, the movement of scholasticism, with its Traditionalist guilds of law, its professional institutions of learning, and its scientific scholastic method, reaches its highest point of development. It has a decisive influence on the civilisation of classical Islam, and beyond it, on the Latin Christian West, in both the intellectual and religious realms, a development discussed in detail in two previous books, The Rise of Colleges and The Rise of Humanism.
The triumphant Traditionalism of eleventh-century Baghdad was not itself without a significant contribution from Islamic Rationalist thought. A secure place for reason had to be made in the make-up of Traditionalism; reason had to be accepted as a genuine constituent element of its composition. Traditionalism received this element from its first ancient adversary, Rationalist Mu'tazilism, in the persons of its own members, as early as the fourth/ tenth century. Abu 'l-Hasan at-Tamimi, known to have been a Mu'tazili, was the grandfather of one of Ibn 'Aqil's professors, Abu Muhammad at-Tamimi. Qadi Abu Ya'la, Ibn 'Aqil's Professor of Law, came from a Mu'tazili family; his father, a Hanafi jurisconsult and Mu'tazili theologian of kalām, died when Abu Ya'la was ten years old. Abu Ya'la is the first Hanbali known to have written works on kalām, of which the Mu'tamad fī uṣūl ad-dīn is but an abridged version of a larger inextant work. Thus Ibn 'Aqil was not the first Hanbali with a Mu'tazili background. But it is he who knew how to integrate into the movement of Traditionalism the elements necessary to revitalise the juridical theology of Shafi'i -- uṣūl al-fiqh, for classical Islam.
The affair of Ibn 'Aqil, within the Hanbali guild, illustrated, in the persons of the Sharīf and Ibn 'Aqil, two orientations of Traditionalism: one fideist, the other intellectualist. Of the two, the latter influenced the