I n February 2022, while he was plugging away at rendering the US writer Dana Spiotta’s novel Wayward into French, the literary translator Yoann Gentric decided he needed a bit of light relief. He would test whether AI could put him out of work.

Gentric had been grappling with a short non-verbal sentence that described the book’s protagonist’s feelings upon opening a window: “Bright, sharp night air, bracing.” He put the prompt into DeepL, a neural-network-powered machine translation engine that regularly outperforms Google Translate in accuracy assessments.

The proposed translation was reassuring, with his job security in mind: L’air de la nuit, vif et vif, était vivifiant ( The night air, lively and lively, was enlivening.) AI had translated the sentence’s meaning but was seemingly unaware that the repetitions rendered the line absurd.…