The story is told of a doctor who had to treat the daughter of a king, and yet could only do so by the use of a knife. While he was gently dressing one of her swollen breasts, he inserted a scalpel hidden in a sponge. The girl would have fought against this cure if it had been openly administered, but because she did not expect it, she put up with the pain. Some cures are only effected through deception.

From Seneca’s “On Anger” in Dialogues and Essays, translated by John Davie, Oxford: Oxford University Press, 2007, p. 49.