In the spirit of my new book on the history of Jewish comedy, I would like to begin by telling you a joke. A Jewish joke, of course; and – perhaps also unsurprisingly – one with a kind of bite to it. It may not be to everyone’s taste; you may not find it laugh-out-loud funny. But it has the benefit – at least in the eyes of this writer – to be the greatest Jewish joke in history. It also, for the historically minded, has the benefit of being one of the earliest, one that – as much as any single joke can do – explains how Jewish humour got to be the way it is.