The heatwave shows the lockdown instinct is still alive

Trains were running even more slowly than usual. Schools were closed again. Offices were empty. No one would deny that Monday and Tuesday were on the warm side, at least by British standards. Even so, there was something more alarming than the temperature: how quickly the authorities started to close down society – and showed that the lockdown instinct is still very much alive.

The Met Office, a body that has turned from fairly comical to slightly sinister in recent times, started advising everyone to stay at home. The unions asked for schools, offices and transport systems to be closed down. There were no trains north out of King’s Cross or Euston, and Luton airport closed completely. Sadiq Khan lost no time in asking people not to have barbecues. We didn’t quite get to the stage where the police were handing out on-the-spot fines to anyone more than five miles from their home, but it may only be a matter of time.

There is a theme running through the behaviour: that of the precautionary principle. It is an invention of recent times: translated from the expression Vorsorgeprinzip (‘foresight principle’), which was coined by German lawyers in the 1970s. Since the early 1990s it has become a stock phrase of public administrators around the world. It means that you don’t need to be sure about potential harm: even a small chance of it can justify taking action. So rather than running a basic cost-benefit analysis – asking if proposed measures are commensurate with risk – safety precautions are taken anyway.

In the face of a threat that only affects a small group of people, help is not directed at those who need it but instead swaths of society are closed down and people advised not to travel.