It was a delicious double irony. The world famous scientist had come to scare the accountants with his bleak statistics about climate change. Slide after slide of his PowerPoint presentation remorselessly depicted graphs showing the grim descent into oblivion. The wealthy and ferociously wealthy were getting twitchy and visibly discomforted – which was precisely the plan.

And then the power went. And it was not a stunt. Cut from his umbilical PowerPoint cord the scientist, who had thus far largely lived up to his charismatic billing, lost his way, his presentation now reduced to a stammering, pitiful shambles.