It is the custom of nature, when she makes a man very excellent in any profession, very often not to make him alone, but at the same time, and in the same neighbourhood, to make another to compete with him, to the end that they may assist each other by their talent and emulation; which circumstance, besides the singular advantage enjoyed by the men themselves, who thus compete with each other, also kindles beyond measure the minds of those who come after that age, to strive with all study and all industry to attain to that honour and that glorious reputation which they hear highly extolled without ceasing in those who have passed away. And that this is true we see from the fact that Florence produced in one and the same age Filippo, Donato, Lorenzo, Paolo Uccello, and Masaccio, each most excellent in his own kind, and thus not only swept away the rough and rude manners that had prevailed up to that time, but incited and kindled so greatly, by reason of the beautiful works of these men, the minds of those who came after, that the work of those professions has been brought to that grandeur and to that perfection which are seen in our own times. Wherefore, in truth, we owe a great obligation to those early craftsmen who showed to us, by means of their labours, the true way to climb to the greatest height; and with regard to the good manner of painting, we are indebted above all to Masaccio, seeing that he, as one desirous of acquiring fame, perceived that painting is nothing but the counterfeiting of all the things of nature, vividly and simply, with drawing and with colours, even as she produced them for us, and that he who attains to this most perfectly can be called excellent. This truth, I say, being recognized by Masaccio, brought it about that by means of continuous study he learnt so much that he can be numbered among the first who cleared away, in a great measure, the hardness, the imperfections, and the difficulties of the art, and that he gave a beginning to beautiful attitudes, movements, liveliness, and vivacity, and to a certain relief truly characteristic and natural; which no painter up to his time had ever done. And since he had excellent judgment, he reflected that all the figures that did not stand firmly with their feet in foreshortening on the level, but stood on tip-toe, were lacking in all goodness of manner in the essential points, and that those who make them thus show that they do not understand foreshortening. And although Paolo Uccello had tried his hand at this, and had done something, solving this difficulty to some extent, yet Masaccio, introducing many new methods, made foreshortenings from every point of view much better than any other who had lived up to that time. And he painted his works with good unity and softness, harmonizing the flesh-colours of the heads and of the nudes with the colours of the draperies, which he delighted to make with few folds and simple, as they are in life and nature. This has been of