Diary – 18 October 2018

When I land on the east coast of America, people tell me they’ve never met a Trump voter. When I land in the middle, as I did last week in Kentucky, I meet lots. I chatted with my driver, who did not like Trump at first, but would vote twice for his re-election if he could, because of the jobs boom and the Brett Kavanaugh hearings. He’s a retired salesman who tutors kids from poor backgrounds in reading and maths. ‘I guess that makes me a conservative,’ he says.

I had to lecture in semi-darkness in Louisville, after a power cut plunged most of the university into darkness. I timed it so that just at the moment when the power company had promised the lights would come back on, I had reached the bit where I said that artificial light is now 60,000 times cheaper than in 1800, in terms of the amount of time you have to work to earn a given quantity of light — a calculation by the economist Bill Nordhaus, who won the Nobel Prize the day before my talk.