Most viewers know Botticelli through one painting — Primavera, the green-floor allegory of spring that became the screensaver of Renaissance art. But Botticelli painted for thirty more years after Primavera. The Birth of Venus extended the project. The Mystic Nativity (1500) inverted it. The Calumny of Apelles (1495-99) abandoned it. The painter who finished his career was almost unrecognisable from the painter who began it, and the gap is the story.

A naked woman stands on a scallop shell, blown ashore by two flying wind gods, while a maid waits with a flowered cloak. Reading the painting that put a pagan goddess back on the wall of a Christian house in 1485.