All the same he was one of the most original minds of all ages, and on the formal side, one of the most revolutionary. He came to Florence early, probably learned his elements under Masolino, but really drew more from the sculptor naturalists of Donatello’s sort. In particular he frequented the surly architect Brunellesco and from him learned the new art of perspective. January 7, 1422, being twenty-one years old, Masaccio was matriculated in the Druggists’ Guild as a licensed painter. By this time he surely had made his great discovery and taken his great decision. Reviewing the painting of his contemporaries and predecessors, he judged that it was all based on unnatural conventions. We can imagine him in the Spanish Chapel viewing the carefully charted and contoured and colored groups, and saying impatiently “things don’t look like that.” And in truth the older painting at its best was a select inventory or formal description of what the artist saw, and not a representation. One can imagine Masaccio exclaiming, as Francisco Goya was to do more than three centuries later, “Lines, always lines, I don’t see them in nature.” And, as a matter of fact, there are no lines in nature, just the meeting of areas variously colored and lighted, contrasts of tone which the eye instantaneously interprets as form. Young Masaccio, then, makes the radical innovation that the brush should work according to nature’s laws, distributing color and light and dark so as to give the swiftest and truest representation of mass and distance. Besides functional light and shade, Masaccio introduced into painting the idea of aerial perspective. He saw that distant objects diminished not merely in size but also in definition. He felt the air as a palpable veil between the object and the eye, and he painted not simply the object but, as well, its veil. By a swift impulse of sheer genius this moody lad fixed ideals of naturalistic painting which were to remain until yesterday and the Impressionists. In fundamental principles Velasquez marks no great advance on Masaccio.