This much is clear and easy of definition; but what is neither clearly understood nor clearly defined is the nature of this union, the manner in which the antique and the modern did thus amalgamate. It is easy to speak of a vague union of spirit, of the antique idea having permeated the modern; but all this explains but little; art is not a metaphysical figment, and all its phases and revolutions are concrete, and, so to speak, physically explicable and definable. The union of the antique with the modern meant simply the absorption by the art of the Renaissance of elements of civilization necessary for its perfection, but not existing in the mediæval civilization of the fifteenth century; of elements of civilization which gave what the civilization of the fifteenth century,--which could give colour, perspective, grouping, and landscape,--could never have afforded: the nude, drapery, and gesture. The naked human body, which the Greeks, had trained, studied and idolized, did not exist in the fifteenth century; in its stead there was only the undressed body, ill-developed, untrained, pinched, and distorted by the garments only just cast off, cramped and bent by sedentary occupations, livid with the plague-spots of the Middle Ages, scarred by the whip-marks of asceticism. This stripped body, unseen and unfit to be seen, unaccustomed to the air and to the eyes of others, shivered and cowered for cold and for shame. The Giottesques ignored its very existence, conceiving humanity as a bodiless creature, with face and hands to express emotion, and just enough malformed legs and feet to be either standing or moving; further, beneath the garments there was nothing. The realists of the fifteenth century tore off the clothes and drew the ugly thing beneath, and brought the corpses from the lazar-houses, and stole them from the gallows, in order to see how bone fitted into bone, and muscle was stretched over muscle. They learned to perfection the anatomy of the human frame, but they could not learn its beauty; they became even reconciled to the ugliness they were accustomed to see, and, with their minds full of antique examples, Verrocchio, Donatello, Pollaiolo, and Ghirlandajo, the greatest anatomists of the fifteenth century, imitated their coarse and ill-made living models when they imagined that they were imitating antique marbles. So much for the nude. Drapery, as the ancients understood it in the delicate plaits of Greek chiton and tunic, in the grand folds of Roman toga, the fifteenth century could not show; it knew only the stiff, scanty raiment of the active classes, the shapeless masses of lined cloth of the merchants and magistrates, the prudish and ostentatious starched dress of the women, and the coarse, lumpish garb of the monks.