Classicism, in the arts, refers generally to a high regard for a classical period, classical antiquity in the Western tradition, as setting standards for taste which the classicists seek to emulate. In its purest form, classicism is an aesthetic attitude dependent on principles based in the culture, art and literature of ancient Greece and Rome, with the emphasis on form, simplicity, proportion, clarity of structure, perfection, restrained emotion, as well as explicit appeal to the intellect. The art of classicism typically seeks to be formal and restrained: of the Discobolus Sir Kenneth Clark observed, "if we object to his restraint and compression we are simply objecting to the classicism of classic art. A violent emphasis or a sudden acceleration of rhythmic movement would have destroyed those qualities of balance and completeness through which it retained until the present century its position of authority in the restricted repertoire of visual images." Classicism, as Clark noted, implies a canon of widely accepted ideal forms, whether in the Western canon that he was examining in The Nude (1956), or the literary Chinese classics or Chinese art, where the revival of classic styles is also a recurring feature. Classicism is a force which is often present in post-medieval European and European influenced traditions; however, some periods felt themselves more connected to the classical ideals than others, particularly the Age of Enlightenment, when Neoclassicism was an important movement in the visual arts. Classicism is a specific genre of philosophy, expressing itself in literature, architecture, art, and music, which has Ancient Greek and Roman sources and an emphasis on society. It was particularly expressed in the Neoclassicism of the Age of Enlightenment. Classicism is a recurrent tendency in the Late Antique period, and had a major revival in Carolingian and Ottonian art. There was another, more durable revival in the Italian renaissance when the fall of Byzantium and rising trade with the Islamic cultures brought a flood of knowledge about, and from, the antiquity of Europe.