Ritratto di un certosino

Petrus Christus signed and dated this in Bruges in 1446, and he did something small and sly with it. Look at the bottom of the painted frame, the reddish ledge under the monk. There is a fly sitting on it, and it is not sitting on the real frame of your museum, it is painted, casting its own little shadow on the panel. In the 1400s a fly could stand for death and decay, fair enough beside a lay brother of the Carthusians in his white habit. But most historians now read it as the painter showing off, a way of saying look how real I can make a thing, real enough that you reached to brush it away. The frame itself is painted too, a fake ledge that pretends to be the edge of a window through which the sitter leans out toward you.