On the gap between your sensorium and your qualia: Wim Hof and the Wedge - Scott Carney's books
Breathing, cold exposure, and other techniques that give you greater resilience and control over yourself
I would like to talk to you briefly about Matryoshka brains.
Classically, this is a Kardashev III sort of phenomenon, where not only do you have a Dyson Sphere around your star, but it’s also made of computronium, and in fact, there’s several nested shells of computronium.
The inner core absorbs all of the star’s energy, and is a seething maelstrom of maximally optimized, furiously paced, high-energy computation. It might hit around 10^38 gigaflops.
Computation generates a lot of waste heat, of course, and it’s a shame to literally *waste* heat in this cold, uncaringly vast universe - so the waste heat from the inner layer radiates out to the next shell out, which uses it for computation of a lower scale and intensity, until eventually you hit about 10^20 flops in the outermost shell and the ability to radiate enough heat to be useful starts tailing off.
What on EARTH does this have to do with breathing or cold exposure, you might reasonably ask?
Well, one of the conceits and more interesting ideas in Scott Carney’s The Wedge is that WE might be like matryoshka brains.
After all, the source of everything you see or smell or feel, the idea of “external reality” entire, happens via a sort of remote interface with sensory apparatus, and it all feeds back to a pomelo-sized bunch of gray goo trapped inside a skull. Your brain can’t SEE. It can’t feel, it can’t talk, it can’t directly perceive anything. It’s trapped, blind and mute, in a wet, dark cave you call your skull.
Your body, that thing of meat and water that actually interfaces and does stuff in the world, actually does quite a bit of processing at many levels, that never really makes it up to “qualia” or conscious attention levels.
You breathe, your heart beats, you digest, your *microbiome* digests, food moves along the digestive tract. Your immune system ceaselessly hunts and deals with intruders, neurons fire in hard-won, coordinated ways to shape non-conscious thoughts and processes, nerve impulses fire in hard-won, coordinated ways to move and maintain the position of your body in space. You perceive and make judgments about your environment faster than your conscious brain can react (as seen in “hand on hot stove,” “unknown thing rushing quickly towards your head causing a flinch reflex” and similar phenomena).
Just to drive home what I’m saying, let’s take digestion and the immune system. Your microbiome and digestion affect your levels of neurotransmitters and firing thresholds - 90% of your body’s serotonin is found in the gut, and your gut contains at least 100M neurons. Your immune system uses neurotransmitters to modulate inflammation levels, activate and suppress immune cells, cause cell migration or cytokine release, and more. Both of these systems respond to things in the environment independently of the brain. They are both quite literally semi-autonomous processing and thinking systems that rarely if ever impinge on your conscious awareness or qualia, but which absolutely affect your experienced qualia, moods, and quality of life.
Your brain might be the central, closest-to-the-source shell of computation, but you have multiple shells of computation going on in your body at all times, and they all talk to each other. They affect what you perceive, and how you feel, and who you perceive yourself to be.
Let’s consider qualia now, or the experience of experiencing something. You have sensory information coming into your brain from your body. But there is a gap - one person can interpret the exact same sensory information entirely differently. It can be experienced as “thrilling,” and it can be experienced as “debilitating,” and the qualia you end up experiencing is literally a CHOICE.
Scott Carney’s books are about that choice - the gap between sensory information and qualia.
The fundamental thesis is that we can consciously modify our own gaps between sensory information and qualia, and become better and more capable people by doing so.
It starts with breathing and cold exposure.
And that starts with Wim Hof, the infamous Dutch guru and extremophile who has graced so many magazine and book covers.
Wim Hof has done so many ridiculously difficult things you can literally fill books with them, so I’ll just hit a few highlights:
He ran a full marathon in the Namib desert in 104+ temperatures, with no water.
He ran a half marathon barefoot in the Arctic, at -20 temperatures.
He summited Kilimanjaro in <31 hours, wearing only shorts and shoes.
He has the longest “submerged in ice” world records, with the latest 1hr and 52 min.
He has - under laboratory conditions - both consciously upregulated and downregulated his immune response, and has taught other people to do the same, also verified in lab conditions.
Scott Carney originally sought Hof out because he thought he was a scammer, a pretend guru that was fleecing people, and he was going to write an exposé. That effort eventually became his book about Hof, What Doesn’t Kill Us.
He went out to investigate, began doing the methods, saw results, and became a convert to breathing and cold exposure. He actually summited Kilimanjaro with Hof, that’s Scott Carney on the left in the Gilman’s Point picture above.
So how does Hof do it? Breathing, mostly.
Breathing is interesting, because it inherently straddles both worlds. Although it operates largely unconsciously most of the time, you can choose to take full conscious control at will. You can breathe deeper, slower, faster, through the nose, through the mouth - nearly every aspect of it is amenable to control.
And as we covered in the review of James Nestor’s Breath, most cultures have thousand year traditions of using different breathing techniques for better health, better athletic performance, and more.
Hof’s techniques are analogous to tummo techniques in ancient Buddhist traditions, which were originally adapted to enable monks to survive in cold caves in the Himalayas.
Hof is more or less a modern-day yogi.1
Hof and other yogis achieve their abilities via different breathing and meditation techniques - by getting good at the interface between conscious and unconscious processes, or The Wedge as Carney likes to call it.
But what if I don’t care about running marathons in the Arctic, why should I care about this?
Because getting better at breathing, and getting better at the Wedge, pays off in lots of mundane ways too.
“Remember, we no longer live in a world where our lives are constantly in danger. Most of the stresses are not going to kill us. So inserting the Wedge here, in the split second that transpires between the external cause of pain and feeling the pain, allows us to act out of deeper purpose and make better choices.”
Let’s talk about homeostasis and allostasis.
As most know, homeostasis is the tendency for the body to revert to the mean, to maintain conditions in the face of random perturbations.
Allostasis is the opposite - it’s kicking your body into a different set point.
Most of the diseases of civilization, which includes depression and anxiety, are a matter of allostasis - your body becoming chronically inflamed.
One method to prevent or ameliorate the diseases of civilization is exercise, as Dan Lieberman (or myself) would tell you. But another way is breathing.
One common theme in a lot of illnesses is higher than normal breathing rates (often 1.5-2x higher), and noticeably lower carbon dioxide blood levels.2
For people with anxiety in particular, they have higher breathing rates coupled with extreme sensitivity to carbon dioxide.3
Breathing more slowly is a choice, and it engages the parasympathetic “rest and digest” system, which calms and relaxes people. The ideal breathing rate is 10 breaths per minute.
If you want another fun example that lives at this Wedge junction, depressed people routinely run a half degree hotter than usual, and don’t sweat.4 Many are depressed because they are inflamed, literally, and that’s what’s driving the higher temperature.
But speaking to the Wedge, do you know what’s correlated with significantly lower depression incidence? Aside from regular exercise, using a sauna regularly.5 Making yourself sweat can prevent depression, and making yourself sweat when depressed can help break the allostasis your body has become stuck in. It’s speaking to a different layer of your matryoshka brains.
The upshot here is that getting more conscious about breathing, trying to slow your baseline breathing, and / or doing breathing exercises like Wim Hof breathing, can make you more resilient, and less likely to get depression, anxiety, and a number of other ills. You can see specific techniques for these things in my Breath review.
Cold exposure is another important part of it.
The benefits of cold exposure are manifold. It activates the parasympathetic “rest and digest” system, increases heart rate variability significantly, improves post-exercise recovery, and literally burns fat.6
But I think the thing that Carney and practioners like myself would point to as the biggest benefit is that is makes you more resilient. Whenever you get into icy water, or turn the shower dial to “full cold,” it’s a sharp shock to the system.
At first, you need to actively fight and suppress the cringe reflex and steel yourself for the norepinephrine dump. Cold exposure is the *epitome* of “the Wedge,” because it’s specifically about taking a pre-qualia bodily-communicated-sensation and choosing to interpret and experience it differently. It’s brisk and invigorating when you’re in the zone, not icy and aversive. It strengthens you, body and mind, if you choose to make it so.
And choosing to make it so makes YOU more resilient overall, both mentally and physically, with Wim Hof himself the example of what you’re capable of at the extremes.
Back to the matryoshka analogy - breathing and cold exposure are two techniques that give you a greater connection and degree of control over some of your other matryoshka shells, because they’re bridges between unconscious and conscious experience. Wim Hof can control his immune system at will because he’s dug deep into breathing and cold exposure, and figured out levers that connect conscious intention and actions to unconscious processes.
Getting better at the junction between sensation and qualia experience is a general skill.
“To steal an example from Brian Mackenzie (an athlete and endurance expert we’ll meet later), consider the relationship between a lion and a gazelle. Imagine the moment when the fearsome predator is just about to go in for the kill. At a physical level, both animals have incredibly similar nervous systems; their blood is chock-full of hormonal cocktails that confer super-mammalian levels of energy. Their pupils open up into saucers and their pain thresholds deepen. The only meaningful difference between their two nervous systems is that the lion is the only one that wants to be there. This is the power of subjectivity. Context is everything.”
In his book The Wedge, Carney does all sorts of things. He does the coldest “Tough Mudder” event in the world, clad only in a bathing suit and a manic grin the whole way. He does ayauhuasca and MDMA. He spends time in sensory deprivation tanks. He does a 5 hour Latvian sauna ceremony designed to keep you redlining just at the edge of your heat tolerance for hours.
All of this is him trying to better understand that junction between sensory information and experience, to better understand how we can live better and more purposeful lives by choosing to interpret our sensations in better ways, and by exposing our bodies and minds to a wider range of sensations and experiences.
In today’s world, comfort is king. We spend 8 hours on a comfy mattress with comfy pillows and sheets and comforters, then we take a shower set at our ideal warmth, then we saunter out into our climate-controlled houses that maintain something close to 72 degrees year round, regardless of outside conditions. We drive in climate controlled cars to climate controlled offices or stores, and then drive back and repeat the cycle again.
Also in our world - 70% of people are overweight or obese, the diseases of civilization run rampant, anxiety and depression are at all time highs, suicide has been steadily trending upwards, everyone is trapped in skinner boxes staring at screens of various sizes for 10-16 hours a day, nobody wants to have kids, political polarization is at all time highs, and it’s a rather grim picture overall.
Do you ever think these things might be connected?
Comfort isn’t your friend, it makes you weak, in mind and body.
Yes, we have a several million year genetic legacy of seeking comfort, because the body can only use its calories for a fixed number of things, and “lazy” people who conserved energy that could be used on reproduction left more descendants over the last few million years. But that doesn’t mean that legacy is RIGHT, or the way to a well-lived life. All it does is turn everyone into Wall-E people.
People who exercise live longer, better lives. In addition to having up to 4x lower all cause mortality versus sedentaries, they have many decades of lower morbidity, and thus decades of higher quality of life. The Dan Lieberman review linked earlier will go into all that at length if you’re interested. But my point is, the effects of exercise are absolutely massive, yet practically nobody does it, because it’s not easy.
Well, I say that “easy” isn’t The Way. If you want to live a life worth living, if you aspire to a life well-lived, you need to choose and do things that *aren’t* easy.
And the Wedge is about doing that.
Better breathing, cold exposure, exercise - they’re not easy, but they are worth it. Especially if they increase your mental and physical resilience.
Especially if they increase your ability to choose your qualia, what you experience, from a broader range of sensations.
Alright, that’s the essential pitch. So what do you do?
Cold exposure:
I would like to point out that the mindset you approach it with matters - if you grit your teeth and see cold exposure as something to endure, it’s not going to last as a habit. If you choose to actively rewrite and reinterpret the shock of cold as invigorating and brisk, and as waking you up and energizing you, it’s a lot easier to stick with it. Specifically, it also helps to “steel yourself,” and choose to not shiver or react when you first get in or feel the cold water / snow. And continuing to choose not to shiver helps activate brown fat thermogenesis.
Cold Showers
Start with ending your showers by turning it to full cold, and staying there for 30 seconds. Remember - steel yourself, don’t shiver. It’s brisk and invigorating, and is waking you up and filling you full of energy - framing matters.
Graduate to actually moving around in that 30 seconds, getting cold water on every part of your body (especially the parts you cringe away from getting water on)
Increase your time to 60 seconds, the last 2 minutes, the last 5 minutes.
Start interspersing your showers with entirely cold showers, and graduate to taking entirely cold showers most of the time
Ice water
A bucket or large bowl full of ice water is enough for at least 2/3 of the experience, because your face has a lot of cold sensitive nerves. Dip your face in the ice water, and hold for 30s. Work up to longer times.
Some people in the tropics rig up a bucket full of ice around their shower head, to take actually cold showers.
If you have the chance to fully submerge or swim in actually cold water, take it! It feels amazing. Once again, do short times at first - 30s, 1 minute, and build your times up gradually.
One hack Brian Mackenzie does in the book which I loved: he uses a big chest freezer in his backyard with water in it, that you can climb into for cold exposure and / or post-exercise recovery. I’m not sure if he took the lid off or had it on a timer or something so it wouldn’t completely freeze, but you could try either of those - I plan on getting one and trying this.
Snow and ice
Naked or swimsuit snow angels, or just sitting in the snow. Once again, start with small time periods, and build up.
Breathing:
I should stress, various traditions have been using various breathing techniques for millenia, and tummo / Wim Hof breathing is just one. In addition to the ones I covered in my Breath review, and the ones Nestor tried that are listed at the end, I’ll also put a few more here, but be aware there is a deep tradition of various breathing techniques from many different cultures if you are interested in trying more.
Wim Hof Breathing
Find a quiet place to lay down. Use a pillow under your head or neck if you feel like it, and relax your body.
Take a very deep, diaphragmatic breath into the pit of your stomach, and let it back out just as quickly. If you put your hand on your belly, your hand should visibly move up several inches as you breathe in, and then back down as you breathe out.
It’s a wave, it comes from your nose to the bottom of your stomach, then back out your stomach, up your chest, and out, in one connected wave. Keep breathing like this for 30-40 breaths.
When you’ve done 30-40, breathe out naturally, leaving about a quarter of the air in your lungs, then hold your breath for as long as possible. As LONG as possible.
When you can’t hold it any more, take a giant breath and hold it for 15 seconds.
Breathe out and repeat the whole cycle another 4 times - you’re back to taking 30-40 quick, full diaphragmatic breaths.
To recap the whole thing:
You’re taking 40 deep diaphragmatic breaths, and letting them out just as quickly as you take them in, then breathing out and holding as long as possible when you hit 40, then breathing a giant breath in and holding for 15 seconds after you couldn’t hold your breath any more, then repeating the 40 breaths. You repeat this cycle 4 times, so you’re breathing 160 fast breaths total.
I actually do Wim Hof breathing every morning, and then do pushups while holding my breath after the fourth cycle - it’s a great way to wake up!
Box Breathing
Box breathing is great for relaxation, calming down, and unwinding.
Breathe in for a count of 4
Hold it for a count of 4
Breathe out for a count of 4
Hold it for a count of 4
That’s it! Very simple and easy. 10-20 minutes or 50-100 breaths is usually good.
Kundalini / split nostril breathing.
Classically, breathing through the left nostril (typically achieved by pressing the right nostril closed with a finger) leads to parasympathetic arousal, which leads to relaxation, better digestion, and calming effects.
Breathing through the right nostril has the opposite effect, of sympathetic arousal, or energizing you, increasing alertness and attention, and engaging “fight or flight.”
Simply choose your left (relaxing) or right (energizing) nostril to breathe from, closing the other one with your finger.
Breathe steadily and slowly for 10-30 minutes or 100-300 breaths from that nostril.
You can also do box breathing or other techniques while doing this.
How long does it take to feel effects? I usually start feeling effects after a minute or two, and most traditions have you do it for 10-30 minutes.
Your body actually naturally alternates between one nostril on the other, on a 30min - 4hr cadence, and the cycling is mediated by erectile tissue in the nose and sinuses.7
Other Wedge Interventions
I think the biggest value you can get out of the book, or this review, is the concept of the Wedge - the idea that there is a gap between sensory experience and qualia, and we can use that gap to consciously change our experiences, and thereby our resilience and our lives, for the better.
Above all, I think, that means we should be open to doing hard things. To being LESS comfortable. To exposing ourselves to greater ranges of temperatures. To doing things which are harder, *because* they are harder.
With that framing in mind, what else might there be?
Sauna
Using a sauna regularly comes with a lot of health benefits, including positive effects on all cause mortality.8 You generally want to keep the temp around 80C (176F). Once you get around 120C (248F), the benefits reverse.
For an additional buff, if you’re an athlete and do “active heat training” in a sauna, it can net you significantly greater performance.9
I think Hot Tubs have a place here too - at least I love and swear by mine. And there’s nothing better than being in the tub while it’s snowing outside, jumping out to make a snow angel and laying there for a while, then getting back in.
Rucking
The biggest thing I got out of Michael Easter’s book The Comfort Crisis was rucking, or walking / hiking / running with a backpack with weight in it. He inspired me to start rucking with that book, and I love it and see the value. I’ve also done it with a weighted vest instead of a backpack.
Rucking is strength and cardio in one package. It trains strength in people who like cardio, and cardio for people who like strength training.
Rucking is used by essentially every military and special forces branch for training resilience and core fitness, and there’s many studies on the benefits. But I’d argue purely from the Lindy effect and ubiquitousness of it in those domains that it MUST have a ton of benefits!
It burns 2-5 times the calories of plain walking, and anywhere you walk, you can ruck. Walking the dogs? Picking up the kids from school? You just put on a backpack!
Marathon, Triathlon, Tough Mudder, OCR’s, maximal athletic effort
I think athletes in particular should value the Wedge. The things that were covered in Alex Hutchinson’s Endure, the techniques that let you reach past the “central governer” and claw back your best performance, are all about the Wedge. The Wedge is that complicated interplay between mind and body that dictates what you can demand and get out of your body at the limits of perception and performance.
To that end, you find and slap right up against the Wedge anytime you’re at your physical and mental limits. One of the interventions that kept popping up in Endure was “positive self talk.” It sounds hokey and ridiculous, and Hutchinson agrees and says he and his teammates used to make fun of the idea. But it shows up again and again in the studies, even for elite athletes. “Positive self talk” is all about framing - it’s about reaching into the gap and rewriting the associations between what your sensorium is telling you, and what you’re actually experiencing. And it works, is the amazing thing!
Similarly, I think if you want a lot of Wedge time, you should push yourself to the limits of your performance, and continually strive to do better. Tackle an Obstacle Course Race or Tough Mudder. Run a marathon. Do some maximal athletic effort regularly (like HIIT), because when you’re at your limits, you’re at the gap, and you’re in a place where you can learn about and deploy the Wedge to greater effect.
What would you get from reading the book(s) yourself?
Carney’s a pretty good storyteller, and keeps everything very relatable. His personal accounts of most of the things he’s undertaken are pretty compelling.
Many takes on the Wedge and performance from the researchers, doctors, and elite coaches and trainers (like Brian Mackenzie) that he talks to throughout the book.
In the Wim Hof book, What Doesn’t Kill Us, a great story of his journey from skeptic, to realizing there might be something to the techniques, to summiting Kilimanjaro shirtless.
Other ideas and directions to go in your own thoughts and potential interventions when considering your own Wedge
Swami Rama, a yogi from India, was studied in the 70’s at the Menninger Clinic in Topeka, Kansas. He could create a temperature difference of 11 degrees between his extremities, raise his heartbeat to 300bpm or lower it to zero for minutes at a time, display delta sleep waves for half an hour and later recount all conversation and events that went on during that half hour, and more. The french cardiologist Therese Brosse recorded a yogi doing similar feats 40 years earlier. A researcher named M.A. Wenger at UCLA tested yogis and found similar abilities.
Diabetes 15 breaths per minute, Asthma 14 bpm, heart disease 12 bpm, cystic fibrosis 18 bpm, liver cirrhosis, 18 bpm
You have chemoreceptors plugged in brain-stem-deep that monitor carbon dioxide levels in your blood, and they can get sort of rigid and “locked in” to a certain range, and it is thought that this is a major factor for anxiety and panic attacks.
Normal people have carbon dioxide blood levels between 5-6%, or ~5.5%. Serious athletes get up to 6.5 - 7.5%. People prone to anxiety average around 5%, and are more sensitive than other people to CO2 increases - any increases in blood CO2 levels pushes them to breathe more, which can lead to a feedback loop of their CO2 decreasing even more, more sensitivity, breathing more and faster, and literally inducing anxiety or a panic attack, mediated by the faster breathing and accompanying higher heartbeat.
It should be noted that lots of people suffer from both anxiety and depression, and anxious people DO sweat, so you only see not sweating in people with depression but not anxiety.
Exposure to a temperature of 80°C led to a significant (p < 0.001) increase in vigor with a simultaneous decrease in tension, depression, anger, fatigue, and confusion.
Brown fat is activated on cold exposure, which burns white “regular” fat cells for energy to maintain your core temperature.
For the other benefits:
Jdidi et al, The effects of cold exposure (cold water immersion, whole- and partial- body cryostimulation) on cardiovascular and cardiac autonomic control responses in healthy individuals: A systematic review, meta-analysis and meta-regression, J. Therm Biol, 2024
Dupuy O, Douzi W, Theurot D, Bosquet L, Dugué B. An Evidence-Based Approach for Choosing Post-exercise Recovery Techniques to Reduce Markers of Muscle Damage, Soreness, Fatigue, and Inflammation: A Systematic Review With Meta-Analysis. Front Physiol. 2018 Apr 26;9:403. doi: 10.3389/fphys.2018.00403. PMID: 29755363; PMCID: PMC5932411.
From James Nestor’s Breath:
“decades passed and nobody offered a good reason for why the human nose was lined with erectile tissue, or why the nostrils cycled. There were many theories: some believed this switching provoked the body to flip over from side to side while sleeping to prevent bedsores. (Breathing is easier through the nostril opposite the pillow.) Others thought the cycling helped protect the nose from respiratory infection and allergies, while still others argued that alternate airflow allows us to smell odors more efficiently.What researchers eventually managed to confirm was that nasal erectile tissue mirrored states of health. It would become inflamed during sickness or other states of imbalance. If the nose became infected, the nasal cycle became more pronounced and switched back and forth quickly.”
“One study tracked 2,315 middle-aged men in eastern Finland over the course of 20 years. The most frequent users, who sat in saunas four to seven times a week, demonstrated a 40% decline in heart attacks and cardiovascular disease as compared with people who sat in one just once a week. Other studies indicate that regular sauna use helps dementia, strokes, Alzheimer’s and, as one article put it, improves on “all-cause mortality events.”
From Ben Greenfield’s Beyond Training: A study of elite rowers saw a 1.5% improvement in 2km rowing performance and 4.5% increase in plasma volume, after active heat training 90 min a day for five days in 104 F 60% humidity. Amazing results for elite level athletes, and for only 5 days of training!