a celebrated painter of the Florentine school, was born in 1402 at San Giovanni in Valdarno. His real name was Tommaso Guidi, but his unfitness for the cares of ordinary life procured for him at an early age the nickname of Masaccio, or "Helpless Tom." Receiving the first lessons in his art from Masolino da Panicale, he was employed under that master in painting the Brancacci chapel in the church of the Carmine at Florence. He also carefully studied the sculptures of Ghiberti and Donatello, and learned perspective from Brunelleschi. About 1430 Masaccio seems to have visited Rome, and there, according to Vasari, he was employed in the execution of several important works. On the return, however, of his patron, Cosmo de' Medici, from exile in 1434, he went back to Florence, and was engaged to complete the paintings of the Brancacci, left unfinished by the death of his old master Masolino. He died, however, in 1443, before he had fulfilled his engagement. The suddenness of his death, and the envy in which he was known to be held by his rivals, combined to originate the suspicion that he had been poisoned.

Ever working with a clear perception that painting is simply a close imitation of nature, Masaccio surpassed all his contemporaries in the easy postures of his figures, in the simplicity and dignity of his draperies, and in his natural and harmonious colouring. So unprecedented was his skill in foreshortening, and his knowledge of perspective, that he may be said to have introduced a new era in the annals of painting. The frescoes in the church of the Carmine at Florence were his masterpieces, and were zealously studied by Raphael and other great painters of the fifteenth and sixteenth centuries. In his epitaph, written by Annibal Cavo, it is said that Michael Angelo was the teacher of other painters, but the pupil of Masaccio.