You know of her, even if you haven’t seen her: The Venus de Milo, Aphrodite of Milos. She’s sculpted from marble, and her name alone speaks of a divine beauty unparalleled by anything mortal. And yet this most famous Venus is broken beyond repair: Both her arms are missing.

As with many celebrated classical statues, our appreciation of the Venus de Milo is shaped by loss. The American writer Charles Fort explained, “To a child she is ugly. When a mind adjusts to thinking of her as a completeness, even though, by physiologic standards, incomplete, she is beautiful.” For archaeologists and historians, these incomplete masterpieces are a puzzle to be solved: Reconstructions of the Venus de Milo suggest her arms were in motion, holding a spinner with a spool or even a spear. But for...