Where do you stand on the Paris consensus? Or should I say: how far along on the path to agreement are you?

For a year or so in my teens I was convinced that I – and almost everybody I knew – would die in a terrifying brain-disease epidemic.

In the second half of 2016, if you found yourself in the right European conference centre at the right time you might have caught a glimpse of that rarest of phenomena: a president, provost or vice-chancellor of an elite academic institution in a moment of self-doubt, contrition even.

It had been billed as ‘Rebellion Day’ by the organisers, a group called Extinction Rebellion that no-one I knew had heard of. Now, after blocking off roads in four major locations in London for over a week, racking up more than 1,000 arrests in the process, lots of people have heard of them.