The secret of success? Self-loathing

Last week, I watched Free Solo, a documentary about 33-year-old Alex Honnold’s attempt to free climb El Capitan in 2017. It’s a horror film. You watch squirming in your seat, as this likeable young man dangles by his fingertips 2,300 metres off the ground in Yosemite. Even the cameraman can’t watch.

Yet he manages it, grinning all the way.