After an enumeration of Raffaello's juvenile works at Cività di Castello and at Perugia, we are told that he who ascribed Sanzio's art to length of study and not to nature, was not acquainted with the powers of his mind.[92] That such was the verdict of Michael Agnolo, is recorded by Condivi; and from aught that appears, it does not seem either invidious or incompetent. If Art be a complete system of invariable rules, he only is a master of Art who substantiates its precepts by equal uniformity of execution and taste; and till he arrives at that point, he can only be said to have seized more or less of its parts in making approaches to the whole, and to be indebted to "study" and not to "nature," if he put himself at last in possession of it. Such was the progress of Raffaello; he arrived by degrees at style in design, by degrees at style in composition, by degrees at invention, expression, and at what appeared to him colour. His genius emancipated him from the shackles of prescription and fashion, rapidly, if we compare his progress with the shortness of his life or the progress of the rest of his contemporaries, but slowly, if we compare him with Michael Angelo, whose system of Art seems to have been born with him, whose infancy, virility, age, exhibit one uniform principle. Every element of the system displayed in the Capella Sistina and on the tombs in S. Lorenzo, may be traced in his essays at the garden of the Medici and in the Holy Family painted for Angelo Doni: but what eye will discover the future painter of the Heliodorus, or the composer of the Cartoons in the bridal arrangements of our Lady's Wedding at Cività di Castello, or even in the Cartoons for the sacristy of the Duomo at Sienna? Though the commission of painting in that place a series of the most memorable events in the life of Pope Pio II. (a Siennese celebrated by the name of Enea Silvio,) had been given to Pinturicchio, who had sufficient modesty and taste to avail himself of the superior and growing powers of his friend,--it has been asked what enterprise of equal magnitude had in that infant state of Art ever been consigned to a single hand, without considering that the co-operation of Raffaello was adventitious, and less owing to the opinion which he had established of himself in the public mind than to the modesty of Pinturicchio. And had not Luca Signorelli singly been entrusted with a work at Orvieto, whose tremendous and universally interesting subjects beyond comparison excelled whatever the embassies, the poetic and papal honours, the canonization of a nun, the ceremonies of a council, the death of the hero himself, and the transportation of his corpse from Ancona to Rome, however varied by character, impressed by the sensibility of the artist, or raised above the heraldry of the times, could pretend to achieve beyond the precincts of Sienna?