Some years ago I gave a mini-lesson on plagiarism to a Chinese student who'd submitted a first essay full of unsourced quotations. I showed her a classical Chinese passage from the ancient Confucian text "The Mencius," in which Mencius quotes and cites Confucius by name.

"See?" I said. "Even ancient Chinese scholars cited their sources." My lesson didn't quite have the desired effect.

Looking back, I shouldn't have been surprised. It would be rather like a Chinese professor quoting the King James Bible to make a moral teaching point to an irreligious British student. Such an antiquarian exercise can fall flat because the teacher presumes, as I did, a historical cultural connection that the student doesn't identify with.