Becket

King. But you must be logical, Becket! Becket. No, that isn't necessary, my Liege. We must only do - absurdly - what we have been given to do - right to the end.

CARDINAL. Sincerity is a form of strategy, just like any other, Holy Father. In certain very difficult negotiations, when matters are not going ahead and the usual tactics cease to work, I have been known to use it myself. The great pitfall, of course, is if your opponent starts being sincere at the same time as you. Then the game becomes horribly confusing.

King. (Anxiously) Isn't that going rather far? Folliot. Of course. It won't fool anyone, but it always works.