Such collapses have occurred many times in human history, and no civilisation, no matter how seemingly great, is immune to the vulnerabilities that may lead a society to its end. Should we find no way to get the wheels back in motion, we’d eventually face total societal collapse. Our world would become an increasingly ugly place, one defined by a scramble over limited resources and a rejection of anyone outside of our immediate group. Should that forward-propelling motion slow or cease, the pillars that define our society – democracy, individual liberties, social tolerance and more – would begin to teeter.

The political economist Benjamin Friedman once compared modern Western society to a stable bicycle whose wheels are kept spinning by economic growth.