Not everyone enjoys smug remarks about sleep. Sleep does not necessarily hasten to “knit the ravelled sleave of care” for all — it did not for Macbeth after his ill-advised venture into murder. He could have taken serious exception to Leonardo da Vinci, if da Vinci said, as reported, “As a well-spent day brings happy sleep, so a life well spent brings happy death.” It is a little difficult to swallow such moralism from a figure as unconventional as da Vinci, particularly since accounts claim that he took 20-minute naps every four hours throughout the day to increase productivity. So, for a well-spent day, he split his happy sleep into a polyphasic cycle of extreme proportions. But the association he makes between sleep and death is almost routine. While many resent these “little slices of death” cutting into life, Martin Luther seems to have drawn a comforting lesson from the association by slightly tweaking the terms. “Whoever drinks beer,” he is quoted as having said, “he is quick to sleep; whoever sleeps long, does not sin; whoever does not sin, enters Heaven.” The lesson is obvious. Let everyone drink beer, said Luther.

Beer, unfortunately, is not a method recommended for the sleep-deprived, but less exciting liquids such as warm milk or chamomile tea. Healthy sleep requires, say the post-Luther generations, a most un-beery approach: fixed times, meditation, switched off phones and screens, a book of poetry or philosophy instead — unquestionably sleepy-making — and maybe a warm bath. Being good, in other words. (Only possible for those with beds, milk and poetry books, of course.) The importance of sleep for physical and mental health cannot be gainsaid, and not having enough of it can lead to the most dangerous illnesses, sometimes incurable ones. But the concerted insistence on seven to eight hours of sleep can be quite unnerving for the ordinary seeker after reasonable rest. It encourages the demand for sleeping pills and yoga classes, while leaving the insomniac frustrated, frightened and as frantic for the life-enhancing eight hours as usual.

Maybe the trick lies in finding the right sleep system for each constitution. Kumbhakarna was quite frank about his. What is needed is the confidence to stare down the threat of eight-hours-or-nothing. Da Vinci is not unlike a host of modern celebrities of various sizes and from different fields in choosing a sleep pattern that suited his unique rhythm of existence.

Nigella Lawson, the much-loved television chef, has been the latest among celebrities to confess to odd sleeping habits: she sleeps in two-hour spells. Not bad. Winston Churchill made do with two hours only. That celebrity extraordinaire and post-truth prophet, Donald Trump, does not need more than three to four hours, and sometimes just 90 minutes. Across the globe, Narendra Modi is the sleepless guard of his country’s interests —metaphorically speaking. Metaphors are the staple of the post-truth world.