Giorgio Vasari, the father of art history, begins his biography of the painter Piero della Francesca with a sigh of reproach:

A truly unfortunate life is the lot of those who pursue their studies in order to be of use to others and promulgate their own fame, but because they fall ill and die, fail to complete the works they began. If they leave them in a state in which only little remains to be done, the incomplete works are snatched up by the impudence of those who attempt to conceal their jackass’s hide beneath the glorious pelt of a lion.

Vasari borrows a fable from Aesop to denounce the plagiarism to which Piero della Francesca fell victim.

Piero was one of those pioneering masters from the circle of Italian humanists who not only practiced their craft as architects and painters, but also wrote theoretical treatises reflecting on their work. We do not know exactly how many essays Piero wrote on mathematics and geometry—Vasari speaks of “many”—but only three have survived. The presumably early Trattato dell’abaco treats arithmetic and algebra. The late De prospectiva pingendi takes up the practical problems of perspective still being debated at the time. Its first sentence is frequently quoted: “Painting contains three main principles, which we call drawing [disegno], measurement [commensuratio], and working with color [colorare].”

Piero’s pictures, invested with so much emotion by modern viewers, are based on a computational foundation of mathematics and solid geometry. The famous Renaissance mathematician Luca Pacioli incorporated Piero’s explanation of solid geometry word-for-word into his Summa de Arithmetica without attribution. It was certainly plagiarism, as Vasari charged, but it was also a compliment. The painter Piero was not just the conceiver but also the constructor of his works.

Although we do not know the exact date of his birth, 2016 is being celebrated as its six hundredth anniversary. He was born in Sansepolcro, a small town in the upper Tiber Valley not far from Arezzo, sometime between 1415 and 1420. His father was a shoemaker. He would have learned the fundamentals of mathematics in the local school, and when he was fifteen he took up painting. We can only speculate on his artistic training in Sansepolcro, and in fact his entire life and career are only sparsely documented, which has led to much wrangling in the scholarly literature.

In 1439 he is mentioned as a colleague of Domenico Veneziano in Florence, and in 1445 he signed a contract to paint an altarpiece for the Brotherhood of the Misericordia in Sansepolcro’s town hall. Thus this first documented commission came not from a prince or a monastery but from his fellow citizens. He would later work for the pope in Rome, for the noble house…