As self-important comics fantasise about unseating Donald Trump with their wit, they should remember the great Aristophanes. In 424 BC, he presented a comedy about the controversial politician Cleon. He was (apparently) the son of a tanner (ugh!), and was seen by contemporaries, including the historian Thucydides, as a ‘brutal’, ‘insolent’ but ‘very persuasive’ braggart — and all too successful.