He knew that his wife’s lively wit needed the stimulus of contradiction, the contradiction of common sense which protests that one cannot (for instance) mistake a woman seriously for a cow; by this process Mme. de Guermantes, enlarging upon her original idea, had been inspired to produce many of her most brilliant sayings. And the Duke in his innocent fashion helped her, without seeming to do so, to bring off her effects like, in a railway carriage, the unacknowledged partner of the three-card player.