Hey, 42 here. In 1915, Hungarian soldier Paul Kern suffered a bit of a mishap whilst fighting the Russians on the Eastern Front of World War I. I say mishap, he was shot in the head. The bullet entered through his temple, utterly destroying part of his frontal lobe.
By all rights, he should have been killed instantly. But somehow, he survived entirely unharmed. Well, almost. Keen mate, a full physical recovery, but he did suffer one small side effect. He completely lost the ability to sleep.
As far as anybody knows, Paul Kern never slept again for the remaining almost 30 years of his life. This complete lack of sleep doesn't seem to have troubled him much either. At least not until his final years, when he began to suffer from a range of neurological symptoms.
Three decades without sleep will do that to you, I guess. Some doctors believe Kern... may have been getting snatches of shut-eye from so-called micro-sleeps, brief periods of unconsciousness throughout the day that he probably wasn't even aware of.
But if he did really stay awake for 35 years straight, then... then his case is probably unique. Because just like food, water and oxygen, sleep is one of Mother Nature's non-negotiables.
A basic requirement to sustain life, not just in humans, but in every single animal known to science that possesses a brain. Considering how fundamental sleep is, it's a little surprising that we don't really know how it works. Like, at all.
We know some of the things that happen inside the brain whilst we sleep. For example, toxins are removed and... memories are processed.
But why exactly we'd need to be unconscious for those things to happen? We have no idea. And how exactly lying down unconscious for a third of our lives to watch brain Netflix makes sense from an evolutionary perspective. Well, still, at least we all know how to do the actual sleeping part, right? Actually, maybe not, because it turns out our entire species might be doing it completely wrong.
So grab yourself a cup of cocoa and slip a hot water bottle under the duvet. This is the story of how human beings forgot how to sleep. In a recent report, we found 53 million Americans aged 18 to 64, 44% of all workers, earn low hourly wages. Yep, this is true, and many people are working in jobs where they are constantly underpaid.
where they are tired physically or mentally, where there's no professional growth, or simply the profession is no longer interesting. And the good news is that this is realistic to change at any time and at any age. Triple Ten Boot Camp has free career opportunities.
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Don't miss out and a big thanks to Triple Ten for sponsoring this video. In the early 1990s, historian Roger Eckert was doing some research for a book he was writing on the history of night time when he stumbled across several sleep-related references that he didn't understand. Here's an example from a novel called Barnaby Rudge by legendary author Charles Dickens.
He knew this even in the horror with which he started from his first sleep and threw up the window to dispel it by the presence of some object beyond the room, which had not been... as it were, the witness of his dream. Notice anything odd about that passage?
Okay, so it's all a bit odd, but there's something specific in there. Dickens'use of the term first sleep. You don't need to have written the book on night time to know that humans are monophasic sleepers. We get all our 40 winks in one big chunk. Apart from the Mediterranean's who practiced a custom of siestas and have a little nap in the afternoon, most of the world only sleeps once per 24 hours.
But going back to that passage, a first sleep seems to imply the existence of a second sleep, a biphasic sleep pattern, and that just didn't seem to make any sense. So what the dickens was dickens on about? Eckert decided to find out. He began scouring various archives in hope of finding more references to biphasic sleep patterns from our recent past.
To begin with, he wasn't particularly optimistic. But to his surprise, it wasn't long before he found some. Actually, it wasn't long before he found lots.
This concept of a first and second sleep seems to have been particularly common in medieval Europe. But Eckert found references from... all over the world in everything from novels and plays to diary entries and court documents.
During just a few months of research, Eckert managed to track down more than 2,000 of them, and putting them all together, he could hardly believe what they meant. Eckert had set out to write a book about the history of nighttime, but somewhere along the way he'd accidentally uncovered a great forgotten truth from our collective past. Until...
Incredibly recently, human beings used to sleep in a completely different way. Not in one single stretch like we do today, but in two distinct blocks, with a few hours wide awake in between. It was a genuinely stunning discovery, and it was made all the more intriguing by the fact that, somehow, the entire human race seems to have forgotten all about it.
So first things first, how did this biphasic sleep thing actually work? There were of course variations from person to person and from place to place, but the general idea went something like this. People would go to bed relatively early compared to today, say around 9pm.
They would then sleep for a few hours before waking up sometime in the early morning. This period of wakefulness was known by different names in different countries. But in England, where this kind of segmented sleep is thought to have been the norm, we called it the watch.
This was a time before alarm clocks, so it's thought that people woke up for the watch naturally in the same way that you'd wake up naturally in the morning, if you didn't have to get up so bloody early for work. As for what people got up to in these wee hours of wakefulness, well, that depended on the person. Some tackled odd jobs around the house or did work for their employers.
Others simply lay in contemplation, digesting the events of the previous day or preparing for the ones ahead. Socialising was common, and some people even went so far as to pop in to visit the neighbours. Prayer was a popular activity during the watch too, as was the chill part of Netflix and chill.
16th century French physician, Laurent Jobeur, apparently claimed that the period between the first and second sleeps was the best time. to conceive. After a few hours doing some combination of these activities, people will go back to bed and sleep for another couple of hours before waking up, as normal, in the morning. Note that this is completely distinct from the modern concept of a siesta, which is typically anywhere from 15 to 60 minutes of napping in the afternoon.
What we're talking about here is two distinct blocks of multiple hours of sleep During the night time, separated by a block of multiple hours of wakefulness. Eckert found references to similar biphasic sleep patterns, dating all the way back almost 3,000 years to ancient Greece. Considering how widespread the practice seems to have been, a coach has even gone so far as to suggest that it may have been the natural way that our species slept for millennia. As interesting as this discovery was, it raised some pretty big questions. Like, if it's natural for humans to sleep this way?
Why did we stop? And when? That second part has a simple, if somewhat surprising, answer. Eckert found references to segmented sleep patterns from as recently as the early 20th century.
That suggests biphasic sleep patterns may... still have been followed as little as 100 years ago. The first part, why did we stop sleeping that way?
Well, that's a little more complicated. To answer that, we're going to have to go back in time a little bit. The world has changed a lot in the last 300 years. years or so, at the start of the 18th century the global population stood at just 660 million people. The most powerful mode of transport in existence was the one horsepower horse, and assuming you were a muggle, air mail was delivered by carrier pigeon.
Humanity was more than 200 years away from mastering powered flight, 100 years from the development of the first vaccine, and 50 years from the invention of artificial refrigeration. Put simply, the modern world is completely and utterly unrecognizable from the one inhabited by our ancestors just a few generations back. And I mean that quite literally.
This is a satellite image taken of the Earth from space earlier this year. We didn't have satellites back in the 18th century, but it isn't hard to show you what the Earth would have looked like back then. All I need to do is turn off the lights.
Artificial light is so ubiquitous these days that most of us take it entirely for granted. We can turn night into day at the flick of a switch whenever we feel like it. But for the vast majority of human history, that wasn't the case. For early hominids and every other animal that's ever lived, the only source of illumination was the kind God was on about when he said, let there be light. In other words, that's provided by the sun, moon and stars.
And two of those are basically the same thing. That meant that nighttime was actually dark. There's a reason children have an innate fear of the dark. Darkness is dangerous.
For early man, it was saber-toothed cats and cave bears. And for our more recent ancestors, the biggest danger usually came from other humans, as it does today. Before the introduction of artificial light, a walk through a forest at night was a journey fraught with genuine existential danger. Darkness has also traditionally been used for the concealment of various nefarious activities, including groves, robbery, violent crime, and prostitution.
All of this meant that for most of human history, it was far safer and far more respectable to stay at home after nightfall. And considering that candles were expensive, most occupations involved fat-breaking work, and there was basically bugger all to do, staying at home meant going to bed early. And so, night time, or more specifically, dark time, was a time for sleep.
And with so much fun, much more time spent in bed, it seems that we naturally shifted towards a biphasic sleep pattern. As weird as that might sound, this general principle has actually been demonstrated in at least one study. In the early 90s, American scientist Thomas Vere set up an experiment in which a group of volunteers spent a month in an environment where the hours of artificially provided daylight were tightly controlled.
Fourteen hours of darkness? 10 of light. For the first couple of weeks, the volunteers slept fairly normally, getting around eight hours a night in one big chunk.
But by the fourth week, something remarkable happened. The participants naturally adopted a segmented sleep pattern. They still slept for about eight hours in total, just with a period of a couple of hours of wakefulness right in the middle.
Sound familiar? For the record, it's worth pointing out that even though it coincided with Akirch's discovery of biphasic sleep in humans, he had nothing to do with this experiment. Veer wasn't researching segmented sleep. This was just a general study of circadian rhythms in humans that happened to suggest we may naturally be biphasic sleepers.
Okay, so now for the million-dollar question. If we all used to sleep in a completely different way, what changed? Well, to put things simply, this.
In 1667, Paris became the first city in the world to light its streets at night. These were just simple wax candles inside glass lanterns. and the illuminations they provided were fairly minimal.
But it was the beginning of the great goodbye for darkness, our old friend. In January 1807, London's Pall Mall became the first street in the world to have gas streetlights. And 70 years later, electric lights appeared for the first time again in Paris.
As ribbons of light spread further across the globe, the very meaning of night began to change. For the first time in history, we were no longer at the mercy of our planet's natural resources. rhythms and so we started to make up our own.
In the 17th century coffee houses began appearing in Europe for the first time, an import from the Ottoman Empire and thanks to the safety offered by newly installed street lighting many were open 24 hours a day and that meant there was actually stuff to do after the sun went down. Who wants to be tucked up in bed when you can be drinking an espresso with your buddies at 2am? As attitudes towards the hours of darkness began to change, people started to naturally go to bed later.
And later bedtime simply didn't leave time for those precious wakeful hours that characterised biphasic sleep. So I guess you could say that it was a combination of gaslighting and FOMO that ultimately killed off segmented sleep. I must admit, I didn't see that one coming.
But the story doesn't quite end there. After all, an entire species changed. its approach to sleep must have had some kind of lasting impact, right?
Well, Roger Eckert certainly thinks it did. Here's a not-so-random interesting fact for you. The word insomnia first entered the English language sometime in the mid-18th century, neatly coinciding with the slow decline of biphasic sleep. Coincidence? Maybe.
Insomnia is clearly a complex illness. It comes in many different forms and there are multiple causes, triggers and symptoms. But the timing is certainly interesting. Eckert had suggested that some forms of insomnia may, in reality, be an echo of our long-forgotten segmented sleep pattern. These days we're taught that we need seven to nine hours of sleep each night, and that to be most effective those hours should come in one uninterrupted stretch.
But in the modern world, of all its many distractions, that's often incredibly difficult. difficult to achieve on a consistent basis. Waking up in the middle of the night can induce immediate panic, as we start worrying about how tired we're going to be the next day.
But maybe it isn't such a big deal after all. If you wake up in the middle of the night, you probably feel like something went wrong. But maybe you're simply waking up because that's what humans did for thousands of years. Far from being a problem that needs fixing, it might be perfectly natural.
That's actually an interesting question. Is segmented sleep natural for humans? Is the apparently very modern monophasic approach to sleep bad? And would we all benefit from switching back?
It's easy to assume the answer to those questions is a resounding... Yes. But it turns out things aren't quite so simple. For one thing, it's hard to be entirely sure that segmented sleep truly always was the natural order of things for humans.
Eckertsch's research has clearly shown that it was once common common, but that doesn't necessarily mean that our ancient ancestors were biphasic sleepers. It doesn't even mean that our recent ancestors were biphasic sleepers. At least, not all of them.
Eckertsch's 2000 plus references are impressive, but they don't allow us to draw definitive conclusions about the whole of humanity. There's a good chance sleep behaviour has changed from era to era and culture to culture. It's also worth remembering that modern humans have never had it so good in the bedroom. Okay, that came out wrong.
But what I mean is, today we are, on average, safer and more comfortable at night than we have ever been before. In the days when segmented sleep was a common practice, communal sleeping was the norm. You'd have shared a straw-filled mattress each night with your entire family and several other people besides. And that's if you were lucky.
Beds and mattresses were expensive commodities that many people simply couldn't afford. For them, it was a nest-like pile of cloth or rags on the floor. Lice, nits, bed bugs and fleas were also extremely common across all social demographics.
And I would challenge anyone to get a good night's sleep whilst a micro zoo of creepy crawlies feasts on your blood. Bedtime was uncomfortable, it was loud, it was cold. And on a bad night you might wake up to that most horrifying of sounds. Your parents having sex in the bed next to you. Concepts like privacy and personal space were very different in the Middle Ages.
It's easy to assume that segmented sleep is the natural way of doing things, because our very unnatural modern technology was likely the key factor in making us switch to a monophasic sleep pattern. But it's perfectly possible that, given the comparatively luxurious sleeping conditions that we have today, at least compared to our ancestors, monophasic sleep is actually the optimal approach. Before I leave you, we still have one final question to tackle, and it's an especially confusing one. According to Eckertsch's research, people were still sleeping biphasically as recently as the 1920s. There may be people alive today whose grandparents, or in extreme cases, even parents, were biphasic sleepers.
So how is it possible that humanity completely forgot such a drastic change to something so fundamental as the way we sleep in such a short space of time? Well, it's hard to say for sure. This kind of mass-scale social amnesia is almost impossible to study.
All we can really do is speculate. But what the hell is YouTube for if not wild speculation? We know that Eckert found references to biphasic sleep from as recently as the early 20th century. But it's important to remember that the majority were significantly older, peaking around the 16th and 17th centuries.
So whilst there clearly were a few biphasic sleepers knocking around as recently as 100 years ago, we can be pretty confident it was no longer the norm. There may be a few outliers whose parents or grandparents followed a segmented sleeping pattern, but the vast majority of us are likely to be multiple generations removed at this point. And with every passing generation, a little more of the past is forgotten. That's just how life works. The other factor at play here is probably simply how mundane the topic is.
Aside from complaining that we haven't had enough of it, how often do we really talk to each other about exactly how and when we sleep? Discovering that humanity used to sleep differently is amazing, but telling the grandkids that in your day you used to sleep in two blocks instead of one is just a boring Sunday afternoon. One thing the vast majority of Akircha's references had in common is that they didn't actually explain what segmented sleep was. Take that first Barnaby Rudge quote.
Dickens didn't take the time to explain what he meant by a first sleep because he simply assumed his readers would already know. That was just how things were done until they weren't. Having said all of that, during my research for this video I learned something pretty interesting. There are still plenty of people around the world who follow biphasic sleep patterns, even today. It seems to be pretty common amongst the elderly.
for example, and there are entire online communities dedicated to sharing ideas on optimal biphasic or polyphasic sleep patterns. So in reality, it never truly went away. Sleep is a genuinely mysterious phenomenon. But exactly how it works and why are the kinds of details that only really matter to scientists. We may not yet fully understand sleep, but we do know just how important it is to our overall health.
As for exactly how you should do it, whether in one block or two, well that's up to you. Thanks for watching. Just a quick word to say that I couldn't make these videos without the support of my Patreon members.
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