ABSTRACT
Twelver Imāmī Shīʿī scholars1 have been concerned with making space for the role of al-ʿaql, reason or rationality, as a normative source since the very earliest moves towards a systematisation of their ideas in uṣūl al-fiqh first began.2 Uṣūl al-fiqh is the theoretical discipline that studies the general principles involved in the inference of religious instructions, or regulative precepts (aḥkām sharʿiyya), from their sources. As the discipline of uṣūl al-fiqh developed, it was not long before al-ʿaql, as an independent source of Sharīʿa precepts, became explicitly incorporated into this theoretical system in the form of what modern Shīʿī legal theorists (Uṣūliyyūn) now refer to as independent rationality (al-mustaqillāt al-ʿaqliyya). The theoretical role of al-ʿaql as a normative source of Sharīʿa, alongside the Qur’ān and the Sunna3 in Shīʿī thought, is linked inextricably to the acceptance of the theological doctrine of the rational intelligibility of the praiseworthy and the blameworthy (al-ḥusn wa al-qubḥ al-͑aqliyyān). This meta-ethical doctrine, often identified as a Muʿtazilī position and referred to as a ‘rationalistic objectivism’,4 is a kind of moral rationalism, a cognitivist theory of ethics that maintains that the values of acts are indeed knowable by humans independent of revelation. This offers an independently intelligible moral framework for Sharīʿa in contrast to the position now dominant across Muslim thought, a position largely shaped by the contrasting Ashʿarī conception of value.5
