The twelfth century, the golden age of feudalism and the Crusades, was also marked by a notable movement of thought and revival of speculative activity. The culture and science which had long found a home at Cordova now began to diffuse themselves over Western Europe, and the works of Avicenna introduced a curious relish for Aristotle’s ‘Natural Philosophy,’ which veiled itself in mysticism to escape ecclesiastical censure. The old scholastic _Trivium_ of grammar, logic, and rhetoric, with the mathematical _Quadrivium_, comprising arithmetic, geometry, astronomy, and music, still constituted the magic circle of ‘Arts’ in the mediæval sense. But the ‘sciences,’ as they were then called, of physics, Roman law, and systematic theology, if not medicine, were now claiming a place in the curriculum of education; and valuable histories, in the form of chronicles, were compiled in several English monasteries. That age cannot be called intellectually barren which produced Lanfranc, Anselm, Abelard, Bernard, Peter the Lombard, Averroes, Gratian, and Maimonides. The University of Bologna, with its School of Law, opened by Irnerius under imperial patronage, was among the first fruits of this mediæval renaissance. The cultivation of Roman jurisprudence is usually dated from the discovery of a copy of the Pandects at the capture of Amalfi in 1135, but it cannot have been wholly unknown at an earlier period, since the religious orders had been forbidden by a Papal mandate to study it. The lectures of Irnerius, however, apparently preceding the capture of Amalfi, methodised and popularised the new learning, which spread rapidly through Western Europe. [Sidenote: Lectures of Vacarius, and first germs of the University]