We have just asked Sir Menzies Campbell when he last poked someone. The face of the Liberal Democrat leader registers utter astonishment, a flush of alarm then a hint of anger. Poking is, we hurriedly assure him, a technical term, from Facebook, which he was the first party leader to sign up to.
“Ah. I was encouraged to do that . . . I’ve got someone who monitors it for me because there are quite a lot of other things going on,” he says.