According to the Observer Magazine of 1 May 1988, one in six people had difficulty sleeping, which from the viewpoint of the climate emergency and pandemic seems like a relatively small percentage denied nature’s soft nurse.

A list of ‘restless spirits’ included Kafka, who sometimes went four consecutive nights without sleep, lamenting in his diary: ‘Toward morning I sigh into the pillow.’ Kipling suffered with insomnia, from the age of 12, and Proust, too, and Lord Rosebery was forced to resign as prime minister because of it. ‘I cannot forget 1895,’ he wrote. ‘To lie, night after night, staring wide awake…’ One suspects our incumbent PM doesn’t have such trouble.

Slightly more troubling was the case of Magdi Yacoub. ‘When he’s not in the operating theatre, our leading heart surgeon is rarely in bed.’ Peter Conrad wrote about his own insomnia (‘the body’s revenge on me’) and how he kept a cache of Harpers & Queen to hand (‘uninteresting… without being boring’), recommending ‘Jennifer’s Diary’ – ‘Her breathless lists of noble names, spliced by hyphens and ceremoniously over punctuated, exactly serve my purpose.’

Another piece analysed the meaning of common dream symbols. Fire? Sex. Swimming? Sex (‘the smoothness of motion through the water indicates the dreamers’ feelings about the act’). Keys and locks? Sex. Drowning? Sex. Doors? Sex (‘the front door is the vagina and the back door the anus’). You get the idea.

How much sleep did we need? About six hours, said Dr Jim Horne. But could we be doing something else with the extra hour or two we didn’t need? Sadly a sort of Parkinson’s law took effect, where sleep expanded to fill the extra time available to it. ‘In other words, unless you have very strong motivation to do something with the time, you might as well accept that the sleep you take, necessary or not, is pleasurable.’ So enjoy your Sunday lie-in and know that ‘sleepiness is the acid test of whether you are getting enough sleep’.