Kathryn Murphy considers the motif of the curtain in painting in works by Adriaen van der Spelt, Piero della Francesca, Rembrandt, Vermeer, and Gerhard Richter.
Murphy writes: "Leon Battista Alberti, in his De pictura (1435), famously recommended that a painting be conceived as an open window through which its subject – the historia – might be seen. To paint a curtain is to interpose something between the viewer and the historia. It is not fully part of the picture; instead it is an invitation both to examine critically the painting’s apparent subject – often, paradoxically, by covering part of it – and to reflect on the claims and limits of realism and representation. A curtain is not supposed to be looked at; the viewer’s instinct is instead, like Zeuxis, to ask what lies beneath."