Several signs denoting the arrival of the annual silly season have appeared recently in the media. This morning the Today programme used a change in the design of the ten pound note to spark a discussion (RealOne Player required) about the superiority of science over the arts.

The old ten pound note with a picture of Charles Dickens on the back is being replaced by one with a portrait of Charles Darwin. After briefly debating the relative merits of Dickens versus Darwin, the host asked one of her distinguished guests what the two men had in common: they were direct contemporaries, belonged to the same London club, and apparently suffered from a chronic “digestive complaint”.

I knew the silly season had begun when the guest quickly added: “I think flatulence was terribly popular in Victorian times”.