When sunlight and raindrops combine they make a rainbow circle invisible to the naked eye. The horizon blocks the lower part, leaving the impression that the rainbow is only the visible arc. Between 1894 and 1920, a dining group of Liberal MPs and members of the Independent Labour Party, known as the Rainbow Circle, aimed to unite their two progressive traditions into one. Somewhere over the rainbow yesterday, Jeremy Corbyn launched his leadership campaign which might mean their ambition is needed again.

Mr Corbyn performed with his now characteristic hopelessness. I had not thought it possible that the Labour leader could surpass in stupidity his remark that Article 50 be triggered immediately, or the speech last week in which he showed that he did not