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Sleep / Rest / Chronotypes Mental Model: Executive Summary
If you only have three minutes, this introductory section will get you up to speed on the sleep / rest / chronotypes mental model.
The concept in one quote:
“Sleep is not an optional lifestyle luxury. Sleep is a non-negotiable biological necessity. It is Mother Nature’s best attempt yet at contra-death. – Dr. Matthew Walker
The concept in one sentence: most Americans believe two theories that have been rigorously dismantled by science: 1, we can do without 8 hours of sleep (we can’t). 2, we can exert control over our circadian rhythm and choose what time to go to sleep and get up (we can’t.)
Key takeaways/applications: sleep is the health and productivity intervention that nobody’s talking about: simply getting a proper night of sleep carries zero opportunity costs while boosting immune function, improving learning and memory, preventing cancer, dramatically improving empathy and productivity, and a whole host of other benefits.
Three brief examples of sleep / rest / chronotypes:
Who needs a prefrontal cortex anyway?
Business managers and anyone who’s undergoing a surgery, take note: a lack of sleep can cause the prefrontal cortex – the rational, logical part of our brain – to remain in an “offline, disabled state.” If you’re sleep-deprived – as 70% of Americans, or anyone who routinely wakes up with an alarm clock, is – you’re literally working without the help of the most powerful part of your brain. Is this the condition in which we want our executives – and surgeons – making decisions?
Drowsy drivers kill more people than drunk and drugged drivers combined.
This is a frightening statistic, considering that public budgets to combat drowsy driving are approximately ~1% of that to combat drunk driving. As I explore in the culture mental model, many professions enforce a completely unscientific “tough it out” approach to sleep – despite the fact that, as Dr. Matthew Walker explains in the phenomenal book “Sleep” , there is no substitute for sleep: not willpower, not caffeine, not nothing.
What is something true that nobody else agrees with you on?
Peter Thiel’s famous “secrets” question, explored in some more depth in “Zero to One” , is one that, for a long time, I didn’t have a pithy answer to. And then it struck me that I did: chronotypes matter. It’s the single most important true-but-unbelieved insight I have to offer to the world after years of reading, studying, and investing for a living. What’s a chronotype? It refers to the midpoint timing of your natural sleep cycle – colloquially known as whether you’re an “early bird” (lark) or “night owl.” Both rigorous scientific research, and my terrifying personal experience, demonstrate that your chronotype is critically important to your health and capacity to make effective decisions, as we’ll explore.
If this sounds interesting/applicable in your life, keep reading for unexpected applications and a deeper understanding of how this interacts with other mental models in the latticework.
However, if this doesn’t sound like something you need to learn right now, no worries! There’s plenty of other content on Poor Ash’s Almanack that might suit your needs. Instead, consider checking out our learning journeys, our discussion of the cognition / intuition / habit / stress, multicausality, or local vs. global optimization mental models, or our reviews of great books like “ Onward” , “The Design of Everyday Things” , or “Deep Survival” .
The Science of Sleep
“Why We Sleep” covers a lot of the scientific research on sleep. A fuller version of the quote that started this model, from Walker’s Google Talk, is as follows:
”Sleep is not an optional lifestyle luxury. Sleep is a non-negotiable biological necessity. It is Mother Nature’s best attempt yet at contra-death. The decimation of sleep throughout industrialized nations is having a catastrophic impact on our health, our wellness, and the safety and the education of our children.
I believe it is now time for us to reclaim our right to a full night of sleep, without embarrassment, and without that terrible stigma of laziness. And in doing so, we may finally remember what it feels like to feel awake during the day.”
Or, as one researcher quoted in Walker’s book puts it, given that all animals known to man (even worms) sleep:
If sleep does not serve an absolutely vital function, then it is the biggest mistake the evolutionary process has ever made. – Dr. Allan Rechtschaffen
The fact that sleep is conserved to such an extent by evolution is mirrored by other activities that might, at first glance, be considered superfluous. In T: The Story of Testosterone, researcher Carole Hooven discusses why mammals spend so much time on play:
“rats, and mammals in general, spend a surprising amount of time engaged in what looks like a frivolous activity – playing. All that tumbling and running around seems to waste valuable energy that could be directed towards other, more sensible activities like finding food… and small, inexperienced animals frolicking, oblivious to their surroundings, are the perfect targets for stalking predators.”
[…] the ultimate explanation for why rats play is because it is a way for young animals to learn and practice adult behaviors that they need to survive and reproduce. When male animals are experimentally prevented from playing in this way; they grow up to be evolutionary losers” who “readily submit to intruders and do not do well in the mating arena.”
As Walker’s book explores in an engaging and fascinating way, sleep is quite possibly the largest contributor to all-cause mortality that can be easily modified at a societal level with zero opportunity costs. We need to build a culture that appropriately values and recognizes sleep.
Here, we’re going to review some of the key findings in Walker’s book, integrating them with another book – Till Roenneberg’s wonderful discussion of chronotypes, called “Internal Time” – as well as research by Christopher Barnes – and a number of other sources I’ve read.
In order, here are brief answers to the questions you never knew you had about sleep, in FAQ format.
Who is sleep deprived?
The vast majority of teenagers, 70% of adults in industrialized nations, and anyone who routinely wakes up with an alarm clock or needs coffee to feel alert and personable upon waking up. Health authorities like the CDC and the WHO call sleep loss an “epidemic.”
What does sleep do for the human body?
Pretty much everything. Walker wasn’t kidding when he called it “Mother Nature’s best attempt at contra-death.”
Sleep is essentially the structural problem solving solution to damn near everything.
– it’s critical to the function of your immune system, including recognizing and killing cancerous tumors before they get too big
– it’s more important to health, ranging from cardiovascular to diabetes to everything else, than diet or exercise
– it enables high-level rational cognition and improves judgment; without sleep, our prefrontal cortex – the rational part of our brain – can remain in an “offline” and “disabled” state
– it dramatically reduces the risk of suicide, dramatically reduces the severity of mental health challenges like depression and anxiety, and may, in fact, prevent them (as well as conditions like schizophrenia) from ever developing in the first place
– it prevents Alzheimers by removing toxic metabolites from the brain,
– it improves memory and learning by consolidating long-term memories,
– it enhances creativity by linking disparate knowledge, while also improving our attention span
– it improves digestion and nutrition absorption (as with many effects, via cortisol/ stress inflammation effects)
– It improves our empathy as measured by our ability to assess emotional states (Walker) and our niceness vs. “jerk-ness” (Barnes)
– it improves our ability to regulate our emotional state by a factor of approximately 2.5x. This leads to behavior as diverse as healthier eating (Walker) and better self-control in the workplace (Barnes, incl the integration of unpublished research on role modeling discussed here)
– it dramatically reduces stress and dramatically improves mood and well-being,
– it improves muscle gain and promotes fat loss,
– It makes us more attractive and, if we’re male, increases the size of our testicles, our sperm count (~30%), and our testosterone levels. (Now I’ve got all the guys paying more attention.)
– It makes doctors 5x less likely to make (potentially fatal) errors when treating or operating on patients,
– Proper sleep would prevent more car accidents than if we entirely eliminated all drugs and alcohol from the world. Both Walker and Christopher Barnes cite research finding that even modest sleep deprivation can be equivalent to being legally drunk from an impairment standpoint.
– it makes us more attractive (Walker) and charismatic (Barnes), as well as more open tofeedback and inspiration (Barnes)
– it also improves ethics and integrity (see Christopher Barnes’ research)
What’s the effect size?
Quite large.
– First, on immune function: merely one night of bad sleep (four hours) can reduce the count of killer T cells – the soldiers in our immune system – by 70%.
– Second, on cognition – Walker cites research that found that when students’ high school start times were delayed by merely one hour, SAT scores improved dramatically. I don’t know why Walker didn’t translate it into percentiles, but I did it for you. Scores on math improved from the 90th to the 97th percentile, and reading from the 73rd to the 99th percentile. You’d be thrilledif an expensive prep course delivered those sorts of results – and you can get them just by giving your kid an extra hour of sleep per night.
– Third, on car accidents – again, starting high school one hour later can reduce teenage traffic collisions by 70%. Among adults, we have a “natural experiment” – an A/B test – called daylight savings time. Every year, on the day we get one more or one fewer hour of sleep, there’s a ~20% impact to cardiovascular incidents (heart attacks) and a ~10% impact to car collisions.
Can’t we do with 6-7 hours of sleep?
Sadly, no. Walker explains that there is a genetic mutation that allows some people to get by on six hours of sleep, but its prevalence is vanishingly small. In terms of base rates, you’re far more likely to be struck by lightning than you are to be able to do okay on 6 hours of sleep. In any sizable group of people, the number who can sleep 6 hours a night and be fine rounds to zero.
Furthermore, Walker explains that people who are sleep-deprived don’t know they’re sleep-deprived – a bit like drunks at the bar who insist they’re good to drive. Bring them into a sleep lab, though, and measurable impairments show up on tests.
What about catching up on the weekends?
Walker explains that you can never fully “catch up” on sleep; many of its benefits, like memory consolidation, are a once-or-never opportunity. You have to get proper sleep every night; you can’t deprive yourself on weekdays and catch up on the weekends (or vice versa.)
Can you get used to less sleep?
Not really. Walker:
“[Individuals] consistently underestimated their degree of performance disability. It was a miserable predictor of how bad their performance actually, objectively was. […]
With chronic sleep restriction […] that low-level exhaustion becomes their accepted norm, or baseline. Individuals fail to recognize how their perennial state of sleep deficiency has come to compromise their mental aptitude and physical vitality, including the slow accumulation of ill health.”
Can too much sleep be bad for you?
Not at all – this is a myth. Walker:
“No biological mechanisms that show sleep to be in any way harmful have been discovered.”
In other words, sleep is not dose-dependent. More is better. Walker notes that there’s a correlation vs. causation problem in mortality data associated with people who sleep a lot: many of the people who are sleeping a lot are seriously or terminally ill, and obviously we sleep more when we’re ill for a variety of reasons. That doesn’t mean that the sleep is the cause of the negative health outcomes; in fact, it’s the other way around.
Anecdotally, for example, one of my friends’ family members who was struggling with advanced multiple sclerosis (MS) “slept about 12 hours a day.” Assuming she is representative of those with her specific condition, certainly a study that included subjects like her would find a correlation between length of sleep and higher mortality, but it’s very difficult to tell a plausible story in which the sleep is the cause of her health issues – rather, it’s the other way around.
Can willpower or caffeine overcome sleep deprivation?
No. Research demonstrates conclusively that neither willpower nor caffeine nor any other substance or technique known to man can replace the need for sleep. In fact, a lack of sleep degrades our willpower: see Barnes’ interview here, for example. Walker also notes that sleep-deprived study subjects:
“showed well over a 60 percent amplification in emotional reactivity […] without sleep […] the strong coupling between [the prefrontal cortex and amygdala] is lost.
We cannot rein in our atavistic impulses – too much emotional gas pedal (amygdala) and not enough regulatory brake (prefrontal cortex). Without the rational control given to us each night by sleep, we’re not on a neurological – and hence emotional – even keel.”
Walker also observes in “Why We Sleep” :
“Sleep deprivation degrades many of the key faculties required for most forms of employment.
Why, then do we overvalue employees that undervalue sleep?
[…] there remains a contrived, yet fortified, arrogance in many business cultures focused on the uselessness of sleep. It is bizarre […]
He cites lots of evidence about medical errors:
“Residents working a thirty-hour-straight shift will commit 36 percent more serious medical errors [… and make…] 460 percent more diagnostic mistakes in the intensive care unit than when well rested.
Through the course of their residency, one in five medical residents will make a sleepless-related medical error that causes significant, liable harm to a patient. One in twenty will kill a patient due to a lack of sleep.”
Take a listen to a doctor himself. Dr. Jerome Groopman, author of “How Doctors Think” , reminisces on his own residency:
“McEvoy’s story of relentless work and sleep deprivation reminded me of the worst moments of my own internship and residency […]
subconsciously, I found myself minimizing the severity of a symptom or assuming that an aberrant laboratory result was an artifact rather than a sign of a serious problem.”
Willpower, similarly, cannot change our chronotype.
What’s a chronotype? Isn’t getting up early just a matter of discipline?
Also no. Meet Till Roenneberg.
Roenneberg is a chronobiologist; he studies the human circadian rhythm – or “biological clock.” His book, “Internal Time” , is virtually unknown and phenomenally important.
The mechanism of chronotypes is a bit technical, but basically our internal rhythms are not naturally 24 hours – they’re usually longer or shorter by a little bit. They “synchronize” to a 24-hour cycle via exposure to daylight. A mathematical equation determines that those with shorter cycles become early birds, and those with longer cycles become night owls. In other words, if you put a night owl in complete darkness, their internal wake-sleep cycle might be over a ~25 hour period. If you put an early bird in complete darkness, their cycle might be over a ~23 hour period.
You can find various stats on it, but the majority of people in modern societies are “late” chronotypes… it follows a quasi-normal-ish distribution with a definite skew toward lateness. See Roenneberg’s book for more.
I explore chronotypes in some more detail in the trait adaptivity mental model, which explains why they evolved and how they got sort of knocked off-kilter. We are supposed to wake up and fall asleep with the sun, with some modest variation in either direction, but the problem is that our bodies synchronize to light, and modern lighting is basically “perpetual twilight” from our bodies’ point of view.
This means that early birds (“larks”) get earlier, and night owls get later.
This is a genetically deterministic outcome; our chronotype is not affected by nurture (essentially, pure nature – see the nature vs nurture mental model), and is no more under our volitional control than our skin color, our sexuality, or any other biological trait.
In other words, telling someone – whether your teenager or employee – that they could get up earlier without feeling groggy if they “just tried harder” is like telling someone that they can change their skin color if they “just try harder,” or telling a gay teen that they can be straight if they “just try harder.”
Chronotypes, just like skin color and sexuality, are biological traits – but as a society, we’ve (errantly) come to believe the myth that they’re a matter of effort, and thus blatantly discriminate against late chronotypes, as I explore in the culture / status quo bias mental model.
As Roenenberg puts it in “Internal Time” , the quality of discussion in public forums regarding chronotypes is often “frighteningly low and shallow.” Roenneberg explains:
“I am often asked whether we cannot get used to given working hours merely through discipline and by confining our sleep habits to certain times. The assumption inherent in this question is that the human body clock can synchronize to social cues.
I tend to find that any such questioner, who usually also displays a somewhat disdainful tone toward the weakness of late chronotypes, is an early type – someone who has never experienced the problems associated with the scallop-shaped sleep-wake behavior of late chronotypes.”
Dr. Matthew Walker, back in “Why We Sleep” , takes it a step further:
“When a night owl is forced to wake up too early, their prefrontal cortex remains in a disabled, ‘offline’ state. Like a cold engine after an early-morning start, it takes a long time before it warms up to operating temperature […]
Sadly, society treats night owls rather unfairly on two counts. First is the label of being lazy […] night owls are not owls by choice. They are bound to a delayed schedule by unavoidable DNA hardwiring. It is not their conscious fault, but rather their genetic fate.
Second is the engrained, un-level playing field of society’s work scheduling, which is strongly biased toward early start times that punish owls and favor larks. Although the situation is improving, standard employment schedules force owls into an unnatural sleep-wake rhythm…”
Most unfortunately, owls are more chronically sleep-deprived [than larks]. […] greater ill health caused by a lack of sleep therefore befalls owls, including higher rates of depression, anxiety, diabetes, cancer, heart attack, and stroke.”
In addition to these productivity consequences, there are dramatic health consequences. A substantial body of research has demonstrated that controlling for all other factors, shift workers (those who have to get up and sleep at unnatural times) have meaningfully higher incidence of pretty much all important mortality-causing health conditions.
Shift work has been labeled a “probable carcinogen” by health authorities – one level down on the scale from cigarettes and HIV. How’s that for contextualization?
Chronotypes are an area where empathy is important – because it is impossible to emotionally understand the perspective of a night owl if you are an early bird. Conversely, early birds deserve a little empathy too – if night owls stay up late with their friends, they have no problem sleeping in the next day, and they’ll feel pretty fine after a good night of sleep. Early birds, however – if they stay up past their bedtimes – tend to have a very hard time “sleeping in,” so they need to be in bed at the proper time if they want to get sufficient sleep.
As such, Roenneberg points out in “Internal Time” that early birds tend to be sleep deprived on the weekends (when there’s social pressure from night owls to stay up or out late), while night owls tend to be sleep deprived during weekdays (when early birds enforce unreasonably early work and school start times on night owls). Obviously early birds have the much better end of the stick, but don’t pick on your early-bird friends if they don’t want to stay up (or out) late with you. They’re not boring – they’re just tired, and they need their sleep!
What about productivity books? Didn’t Ben Franklin say “the early bird gets the worm?”
A fun fact is that Benjamin Franklin actually didn’t even follow this advice for much of his life; he stayed up pretty late living it up when he was in France.
I discuss this in more depth in the culture mental model, but summarily, there are a few angles here.
First is that the early-bird proverbs, as Roenneberg explains, totally made sense in a pre-Industrial era. But that was before artificial light – we don’t work in the fields anymore; even if we do, sundown no longer means we lose our chance to work. Indeed, our chronotypes have gotten later and later as we’ve been using more and more lights (particularly blueish lights and computer / electronic device screens), but culture / status quo bias has kept work hours the same. This results in a strange situation: Roenneberg observes in “Internal Time” that:
“In view of the lateness of most people in our modern societies, one could argue that a majority of the workforce is scheduled in a permanent early shift when they work from nine to five.”
Second is that given the way trait adaptivity and selection pressure work, Roenneberg hypothesizes that the earlyness of the professional world *selects for* people who are early birds – in other words, many people who rise up the ranks of corporations tend to be early types, which isn’t surprising if they’re getting to use their prefrontal cortex while the night owls aren’t.
So the corporate environment, by virtue of its early start times, selects against night owls, notwithstanding their level of talent and drive, and selects for early birds, even if they’re inferior on every other useful trait. That leads to a feedback cycle – it’s intuitive, but also empiric. Research by Christopher Barnes (unpublished) indicates that leaders in organizations basically role-model and perpetuate their own preferred sleep behaviors.
So you have to use Bayesian reasoning and filter that sort of advice through the science, and what you know about your own body.
What’s Walker’s recommendation for how businesses should operate, based on the actual science?
“everyone would be present during a core window for key interactions – say, twelve to three p.m. Yet there would be flexible tail ends either side to accommodate all individual chronotypes.
Owls could start work late (e.g., noon) and continue into the evening, giving their full force of mental capacity and physical energy to their jobs. Larks can likewise do so with early start and finish times.”
Does chronotype vary by age?
There’s a reason that teens are notorious for sleping in. Both Roenneberg and Walker address the fact that teenagers’ chronotypes are biologically the latest of any period in their life. No matter our chronotype, we tend to be earlier as little kids, much later as teenagers, and then gradually earlier as we age (which explains 5 PM senior specials, if you were wondering.) Teenagers, in fact, display symptoms of narcolepsy if you wake them up at school start times and bring them into a sleep lab (from Roenneberg’s book.)
Roenneberg and Walker thus both spend a lot of time discussing the tragic and terrible impact that early school start times are having on your teenager’s health, learning, and emotional stability. (Barnes talks about it too.)
I’ll cite Walker here from “Why We Sleep” with a fantastic, empathy creating analogy:
“Asking your teenage[r] to go to bed and fall asleep at ten p.m. is the circadian equivalent of asking you, their parent, to go to sleep at seven or eight p.m.. No matter how loud you enunciate the order, no matter how much that teenager truly wishes to obey your instruction, and no matter what amount of willed effort is applied […] the circadian rhythm of a teenager will not be miraculously coaxed into a change.
Furthermore, asking that same teenager to wake up at seven the next morning and function with intellect, grace, and good mood is the equivalent of asking you, their parent, to do the same at four or five a.m.
[…] teenagers’ sleep patterns [… are] non-volitional, non-negotiable, and strongly biological. We parents would be wise to accept this fact […] and praise it, lest we wish our own children to suffer developmental brain abnormalities or force a raised risk of mental illness upon them.”
Walker goes on to note that it’s a myth that teenagers have always gotten up this early for school:
“Our children didn’t always go to school at this biologically unreasonable time. A century ago, schools in the US started at nine a.m. As a result, 95% of all children woke up without an alarm clock.
Now, the inverse is true, caused by the incessant marching back of school start times – which are in direct conflict with children’s evolutionarily preprogrammed need to be asleep during these precious, REM-sleep-rich morning hours.”
In my view, current school start times are essentially legalized and societally-condoned child abuse that would be wildly unacceptable to me as a parent. It’s one of the many reasons my wife and I plan to homeschool… unfortunately, short of that, there’s not much you can do about it.
I’m a night owl working for a company that is entrenched in early-bird culture. What do I do?
A few options here.
First, take the time to understand the underlying mechanisms of chronotype entrainment (which I, unfortunately, had neither the energy nor knowledge to do when I was suffering.) Roenneberg’s book “Internal Time” provides all the information you need.
One of the most fascinating discussions in his book was a mention of some research in which people went camping (for science) and all of a sudden, they all woke up and fell asleep as nature intended – with the sun. There was still variation, but it was substantially more modest than is seen in the modern world.
I see this myself as an avid backpacker – whenever I’m hiking and camping, I’m pretty well able to get up 30 minutes to an hour after dawn, which is perhaps not early but certainly not 11 am or noon (which is my usual time in digital-era lighting.)
Summarizing some of the technical stuff, one of the signals for sleep onset is a hormone called “melatonin.” If you get a lot of light early in the day, that helps compress your clock, and you’ll feel sleepy earlier.
But conversely, if you get a lot of light late in the day, that extends your clock, and you’ll feel sleepy later, and not be able to fall asleep. And, frustratingly and paradoxically, research demonstrates that it’s often hardest to fall asleep right before you’re supposed to fall asleep – that’s actually the hardest window in which to snooze (other than right after you wake up from a full night of sleep, for obvious reasons).
Finally, be aware that it’s not *all* light – but only blue light – that entrains the circadian rhythm. So if you can avoid blue light and look at red light instead, that helps you not delay melatonin onset. You can do this by several methods – one is to use your device’s settings to have a “night light” – Windows 10 ships with this and so does my smartphone; I believe there are also third party apps. Failing that, a pair of cheap red-tinted drugstore sunglasses would probably help a bit.
On top of all that, melatonin is often helpful. I take melatonin myself; Walker claims it’s all placebo effect, but I don’t think his position is internally consistent, nor is that view consistent with the underlying causal mechanism of circadian rhythms and sleep onset, nor is it consistent with the research cited by Roenneberg on children with Smith-Magenis syndrome (where what were thought to be behavioral problems were actually caused by sleep deprivation due to an inverted melatonin rhythm – fixable by beta-blockers and melatonin at the right times.)
So, to review, if you need to get up earlier than you want for your job:
– get as much bright light as you can early in the day. (start an herb garden and water it, or go for a walk, or something.)
– avoid as much blue light as you can after sunset
– consider taking melatonin 30 minutes to an hour before bedtime
What about alcohol and caffeine?
Walker says no to both, although I think that’s a bit of overkill. Alcohol suppresses REM sleep; caffeine also reduces the quality of sleep. I’ve never drank anyway, but Walker recommends total abstinence. As for caffeine, I’ve gone down from 3 to 2 to 1 cups of coffee per day over time and it’s definitely helped my sleep. Walker seems to recommend abstinence here too, but I love my specialty coffee and I get plenty of sleep, so, you know, live a little.
How are naps?
Tricky. They are great at the right time – Walker’s a huge fan, and cites some evidence suggesting they are cardioprotective and can enhance learning and so on – but if you take them at the wrong time, you’ll just push your sleep onset at night farther off to the right. So, I don’t feel comfortable opining briefly – just keep that in mind as a topic to really study when you read the book. Soojung-Kim Pang talks about naps too (see reference below).
Personally, I don’t really nap much right now, unless I have to get up really early for something, or if I’m sick, or something. Sleep at night is fine for me. But I will say that naps were probably the only thing standing between me and a complete nervous breakdown when I worked at my job.
If I get enough sleep, then I can work the rest of my waking hours and be fine, right?
No, not that either. Rest while awake is also important. Alex Soojung-Kim Pang’s “ Rest” goes into this. Please note that Soojung-Kim Pang is one of those people who doesn’t understand the science and thereby falls for the “morning trap” – he advises everyone get up early, as I take him to task for in the notes on the book – but the fact that he’s brutally wrong on that issue doesn’t mean he’s wrong about much of the rest of his work.
Soojung-Kim Pang explores how we’re often more productive and creative when we’re not working all the time; I’m not sure I believe his exact numbers, but I’ve seen plenty of research suggesting that working 60 hours a week is generally no more effective than working 40 hours – because of the opportunity costs of fatigue and burnout.
Indeed, survival experts like Laurence Gonzales highlight the importance of rest in life-or-death contexts. Gonzales, in his phenomenal ‘ Deep Survival” , notes that it’s important for both the sake of body and mind that you take it easy. No sweating; lots of rest and hydration.
In less dire circumstances, as I discuss in the product vs. packaging mental model, many famous luminaries like Darwin and the scientists who built the atomic bomb (see “The Making of the Atomic Bomb”) were the opposite of butt-in-chair types.
They walked around, took baths, and that’s where they came up with their best ideas. And those are often what are really important – mindless busyness, as Stephen Covey puts it in “ The 7 Habits of Highly Effective People,” is like chopping down trees in the “wrong jungle!”
Is There An AI Angle?
Yeah, this one’s pretty easy: outsource your tedious work to AI so you can spend more time sleeping!
