Virginia Postrel on the egos behind Renaissance art:

Know what to look for and Florentine artworks reveal secret messages that, while not as sexy as Dan Brown’s Mona Lisa fantasies, have the advantage of actually existing.

Take the boys shown walking up the stairs behind their tutor in Domenico Ghirlandaio’s fresco in the Santa Trinita church. What could these kids have to do with the “Confirmation of the Rule of Saint Francis,” the official subject of the fresco? They aren’t friars or church officials.

In fact, their portraits are just good public relations. The patron, a banker named Francesco Sassetti, included them to butter up their father, Lorenzo de’ Medici, and to let the churchgoing public know that he and Lorenzo were tight.

But the painting doesn’t tell the whole story. It “conveniently omits a crucial fact about the patron’s relationship with the Medici,” write art historian Jonathan K. Nelson and economist Richard Zeckhauser in their book, “The Patron’s Payoff,” which uses economic signaling theory to analyze Renaissance patrons’ motivations and techniques. That fact: “By the time he commissioned the fresco, Sassetti had nearly run the Geneva branch of the Medici bank into bankruptcy.” Oops. Maybe the portraits were meant as a distraction or damage control. How could you fire (or worse) a man who had sponsored such fine pictures of your kids?

Nelson and Zeckhauser’s work demonstrates that Renaissance art is full of status signals and calculated image-building -- once-obvious messages that today’s tourists never notice.