Shii school of Islamic law relying on a series of rational processes dating to at least the twelfth century. Opposed to traditionist Akhbaris. Favored the exercise of ijtihad (independent reasoning) by those qualified to carry it out and obedience to these rulings (taqlid) by those not capable of exercising ijtihad themselves. The most important legacy of the movement is the selection of scholars to be imitated, known as marja al-taqlid; the teachings of the most respected scholar of the time are to be adhered to. Obedience to practitioners of ijtihad became a religious duty for Shiis, elevating the status of jurists and profoundly impacting Iranian history and society by setting the stage for the political activism of Shii ulama in the nineteenth and twentieth centuries. The movement can be regarded as the precursor to the Islamic revolution of 1978–79.