THE DAILY PIC: Yesterday, in this same space, I compared Cézanne’s Card Players at the Barnes Foundation to Renaissance altarpieces–not knowing that the following day I’d be among precisely such paintings, in the Piero di Cosimo exhibition at the National Gallery in Washington, which may just be the most fascinating show in the country right now. So go ahead and compare this Visitation by Piero, from around 1490, with yesterday’s Cézanne–while I move onto a completely different issue.

At the bottom left of Piero’s altarpiece, as one of the symbolic “attributes” of Saint Nicholas of Bari, Piero included the holy man’s customary golden balls, which stood for the wealth that he gave away. What fascinates me about those balls (see the detail below) is the tiny, barely visible reflection that he put into the leftmost one of them, in which we can just glimpse the interior of the church that the picture was originally sitting in–that is, the church space that was behind and all around the Renaissance viewers of the piece. (And that, as it happens, was in the midst of restoration by Piero’s friend the great architect Giuliano da Sangallo.) It’s a truism that Renaissance pictures often tried to pretend, at least notionally, that they gave us a view through a hole in the church wall and onto a sacred world beyond. Here, Piero fleshes out that truth by letting us see both sides of the pierced space at once. He lets light pass from the real space of the church to the fictional space of the picture’s story, both as that light bounces into his golden ball and reflects an image off it, but also in the illumination on his painted saints, which comes from our side of the picture and casts shadows back into the space of their world. Giorgio Vasari, the Renaissance “father of art history”, said that with those balls Piero demonstrated the “strangeness of his brain, and his constant seeking after difficulties.” Also, his solutions to them. (National Gallery of Art, Washington, Samuel H. Kress Collection)

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