‘Tell us about this man Keel,’ said the major. ‘I don’t know nuffin’,’ said Nobby automatically. ‘Aha, that means you do know something,’ said the major, who was indeed the sort of person who liked this kind of little triumph. Nobby looked blank. The captain leaned forward to whisper to his superior officer. ‘Er, only under the rules of mathematics, sir,’ he said. ‘Under the rules of common grammar, he is merely being emphat—’ ‘Tell us about Keel!’ the major shouted.

— Night Watch (Discworld, #29; City Watch, #6) by Terry Pratchett (Page 264)