Epistemic Spot Check: Full Catastrophe Living (Jon Kabat-Zinn)

Full Catastrophe Living is a little weird, because between the first edition and the second a lot of science came out testing the thesis.  For this blog post, I’m reviewing the new, scienced-up edition of FCL.  However I have ordered the older edition of the book (thanks, Patreon supporters and half.com) and have dreams of reviewing that separately, with an eye towards identifying what could have predicted the experimental outcome.  E.g. if the experimental outcome is positive, was there something special about the model that we could recognize in other self-help books before rigorous science comes in?

I originally planned on fact checking two chapters, the scientific introduction and one of the explanatory chapters.  Doing the intro was exhausting and demonstrated a consistent pattern of “basically correct, from a small sample size, finding exaggerated”, so I skipped the second chapter of fact checking. I also skipped the latter two thirds of the book.


You’ve probably heard about mindfulness, but just in case: mindfulness is a meditation practice that involves being present and not holding on to thoughts, originally created within Buddhism.  Mindfulness Based Stress Reduction is a specific class created by the author of this book, Jon Kabat-Zinn.  The class has since spread across the country; he cites 720 programs in the introduction.   Full Catastrophe Living contains both a playbook for teaching the class to yourself, the science of why it works (I’m guessing this is new?), a section on stress, and followup information on how to integrate meditation into your life.


Claim: Humans are happier when they focus on what they are doing than when they let their mind wander, which is 50% of the time.

Accurately cited, large effect size, possible confounding effects. (PDF).  The slope of the regression between mind wandering and mind not-wandering was 8.79 out of a 100 point scale, and the difference between unpleasant mind wandering and any mind not-wandering task was ~30 points.  Pleasant mind wandering was exactly as pleasant as focusing on the task at hand.  Focusing accounting for 17.7% of the between-person variation in happiness, compared to 3.2% from choice of task.

Some caveats:

  • People’s minds are more likely to wander when they’re doing something unpleasant, and when they are having trouble coping with that unpleasantness.   The study could be identifying a symptom rather than a cause.
  • The study population was extremely unrepresentative, consisting of people who chose to download an iPhone app.

Claim: Loss of telomeres is associated with stress and aging; meditation lengthens telomeres by reducing stress (location 404).

Research slightly more theoretical than is represented, but theoretical case is strong. (Source). First, let’s talk about telomeres.  Telomeres are caps on the ends of all of your chromosomes.  Because of the way DNA is copied, they will shorten a bit on every division.  There’s a special enzyme to re-lengthen them (telomerase), but leading thought right now is that stress inhibits it.  Short telomeres are associated with the diseases of aging (heart issues, type two diabetes) independent of chronological age.  This is hard to study because telomere length is a function of your entire life, not the last week, but is pretty established science at this point.

Mindfulness reduces stress, so it’s not implausible that it could lengthen telomeres and thus reduce aging.  The authors also present some evidence that negative mood reduces the activity of telomerase.  This is a very strong theoretical case, but is not quite proven.

Claim: Happiness research Dan Gilbert claims meditation is one of the keys to happiness, up there with sleep and exercise (location 461).

Confirmed that Gilbert is a happiness researcher and said the quote cited, although I can’t find where he personally researched this.

Claim: “Researchers at Massachusetts General Hospital and Harvard University have shown, using fMRI brain scanning technology, that eight weeks of MBSR training leads to thickening of a number of different regions of the brain associated with learning and memory, emotion regulation, the sense of self, and perspective taking. They also found that the amygdala, a region deep in the brain that is responsible for appraising and reacting to perceived threats, was thinner after MBSR, and that the degree of thinning was related to the degree of improvement on a perceived stress scale.” (location 502)

Accurate citation, but: small sample size (16/26), and for the first study the effect size was quite small (1%) for regions of a priori interest, and the second had quite wide error bands (source 1) (source 2).  However the book does refer to these findings as preliminary.

Claim: “They also show that functions vital to our well-being and quality of life, such as perspective taking, attention regulation, learning and memory, emotion regulation, and threat appraisal, can be positively influenced by training in MBSR.” (location 508).

Misleading.  These are really broad claims and no specific study is cited.  However, source 2 above has the following quote: “The results suggest that participation in MBSR is associated with changes in gray matter concentration in brain regions involved in learning and memory processes, emotion regulation, self-referential processing, and perspective taking.”  This is a very carefully phrased statement indicating that mindfulness is in the right ballpark for affecting these things, but is not the same as demonstrating actual change.

Claim: “Researchers at the University of Toronto, also using fMRI, found that people who had completed an MBSR program showed increases in neuronal activity in a brain network associated with embodied present-moment experience, and decreases in another brain network associated with the self as experienced across time. […]  This study also showed that MBSR could unlink these two forms of self-referencing, which usually function in tandem.” (location 508).

Accurate citation, small sample size (36) that they made particularly hard to find (source).  I can’t decipher the true size of the effect.

Claim: Relative to another health class, MSBR participants had smaller blisters in response to a lab procedure, indicating lower inflammation (location 529).

True, but only because the other class *raised* inflammation (source). Also leaves out the fact that both groups had the same cortisol levels and self-reported stress.  So this looks less like MBSR helped, and more like the control program was actively counterproductive.

For the record, this is where I got frustrated.

Claim: “people who were meditating while receiving ultraviolet light therapy for their psoriasis healed at four times the rate of those receiving the light treatment by itself without meditating.” (location 534)

Accurate citation (of his own work), small sample size (pdf).

Claim: “we found that the electrical activity in certain areas of the brain known to be involved in the expression of emotions (within the prefrontal cerebral cortex) shifted in the MBSR participants in a direction (right-sided to left-sided) that suggested that the meditators were handling emotions such as anxiety and frustration more effectively. […]

This study also found that when the people in the study in both groups were given a flu vaccine at the end of the eight weeks of training, the MBSR group mounted a significantly stronger antibody response in their immune system”

Accurate citation (of his own work), slightly misleading, small sample size.  Once again, he’s strongly implying a behavioral effect when the only evidence is that MSBR touches an area of the brain. On the other hand, the original paper gets into why they make that assumption, so either it’s correct or we just learned something cool about the brain.

Claim: MSBR reduced loneliness and a particular inflammatory protein among the elderly (location 551).

Not statistically significant. (source)  More specifically; the loneliness finding was significant but uninteresting, since the treatment was “8 weeks with a regular social activity” and the control was “not.”  The inflammation finding had p = .075.  There’s nothing magic about p < .05 and I don’t want to worship it, but it’s not a strong result.

I also researched MBSR in general, and found it to have a surprisingly large effect on depression and anxiety.

The Model

To the extent Full Catastrophe Living has a model, it’s been integrated so fully into the cultural zeitgeist that I have a hard time articulating it. It could be summarized as “do these practices and some amount of good things from this list will happen to you.” Which kills my hypothesis that having a good model is necessary to getting good results.


You Might Like This Book If…

I don’t know. I found it a slog and only read the first third, but the empirical evidence is very much on mindfulness’s side and I don’t know what better thing to suggest.




Thanks to the internet for making it possible for me to do these kinds of investigations.

Thanks to Patreon supporters for giving me money.



Epistemic Spot Check: Exercise for Mood and Anxiety (Michael W. Otto, Jasper A.J. Smits)


Everyone knows exercise (along with diet and sleep) makes a big difference in depression and anxiety.  Depressed and anxious people are almost by definition bad at transforming information about how to improve their lives into actions with large up front costs, so this data is not as useful as it might be.  Exercise for Mood and Anxiety (Michael W. Otto, Jasper A.J. Smits) aims to close that gap by making the conventional wisdom actionable.  It does that through the following steps:

  1. Present evidence that exercise is very helpful and why, to create motivation.
  2. Walk you through setting up an environment where exercise requires relatively little will power to start.
  3. Scripts and advice to make exercise as unmiserable as possible while you are doing it.
  4. Scripts and advice to milk as much mood benefit as possible from a given amount of exercise.
  5. An idiotic chapter on weight and food.


Parts 3 and 4 use a lot of techniques from cognitive behavioral therapy and mindfulness, and I suspect there’s a second order benefit of learning to apply these techniques to a relatively easy thing, so you can apply them to the rest of your life later.

Epistemic Spot Checking

Claim: “a study of 55,000 adults in the United States and Canada found that people who exercised had fewer symptoms of anxiety and depression.” (Kindle Locations 103-104). 

Correctly cited, paper has no proof of causation.  (abstract) (PDF) The study does in fact say this, but it also says “Despite the fact that none of these surveys [of which this paper is a metaanalysis] was [sic] originally designed to explore this association… “.  I’m not saying you can never repurpose data, but with something like this where the real question is causality, it seems suspicious.  The authors do consider the idea that causation runs from mental health (=energy, hopefulness, executive function) -> exercise and dismiss if, for reasons I find inadequate.

Claim: “Other studies add to this list of mood benefits by indicating that exercise is also linked to less anger and cynical distrust, as well as to stronger feelings of social integration.” (Kindle Locations 104-106). 

Correctly cited, paper has no proof of causation. (Abstract).

Claim: And these benefits don’t just include reducing symptoms of distress in people who have not been formally diagnosed with depression or anxiety. The benefits of exercise also include lower rates of psychiatric disorders; there is less major depression, as well as fewer anxiety disorders in those who exercise regularly. (Kindle Locations 107-109). 

Correctly cited, paper has no proof of causation.

The dismissal of causality goes on for another three citations but I’m just going to skip to the intervention studies.  Otto gives these population studies more credence than I would but does note that the intervention studies are more informative.

Claim:  study summarized 70 studies on this topic and showed that adults who experience sad or depressed moods, but not at levels that meet criteria for a psychiatric disorder, reliably report meaningful improvements in their mood as they start exercising. (Kindle Locations 116-117).

Correctly cited, study accuracy undetermined.  (Full paper). My fear (based on spot checking a similar book you’ll see in the rejects post) is that each of these studies consists of 15 people.  All the metaanalysis in the world won’t save you if you do 100 small studies and only publish the 50 that say what you want.  The studies included go all the way back to 1969: I can’t decide if that makes them more informative or less.

Claim:  The latest estimates are that about 17% of adults experience a major depressive episode in their lifetimes and that about half who have it experience recurrent episodes over time. (Kindle Locations 124-126). 

True. (Full paper).  The same study is cited for both facts, but I can only find the 50% statistic in the paper.  The data is kind of old (started in 1981), but of course you can’t get 30-year data except by starting 30 years ago.  This paper says the lifetime prevalence of mood disorders (depression, bipolar 1 and 2, and their baby siblings) is 20%; this study puts prevalence in the US at 16.9%.

Claim: As is the case with major depressive disorder, anxiety disorders are common, affecting more than 1 in 4 (28.8%) adults in their lifetimes” (Kindle Locations 136-137).

True. (Full paper).  He cites the same paper I did for the 20% mood disorder statistic.

Claim: [Anxiety disorders] tend to be especially long-lasting when people do not receive treatment. (Kindle Locations 137-138).

True, although not particularly specific.  (Full paper)

Claim: Exercise in itself is a stressor—it requires effort, and it forces the body to adapt to the demands placed on it.  (Kindle Locations 141-142). 

True.  (Full paper).

Claim:  A study examined firefighters reaction to stress, and then gave half a 16 week exercise course.  The study group showed improvements in stress responses. (Kindle location 148)

True.  (Abstract) (PDF).  I really like this study.  The group presumably had a high baseline fitness level, so this isn’t the difference between couch potato and a walk.  And they have before and after metrics.  The study is marred only by the small sample size (53).

Claim: “stress plays a key role in both the development and the continuation of depression and anxiety disorders.” (Kindle Locations 152-153). 

Accurate citation, very complicated topic. (Abstract).

Okay, it is becoming clear I don’t have the time to check every one of these citations and you don’t have time to read it.  From here on out please assume a baseline of very dense citations, all of which accurately report the study results, if with a little more confidence than the study design merits, and I’m only going to call out things that deserve special attention on account of controversy or importance.

Claim: exercise increases serotonin just like the primary class of anti-depressants, selective serotonin update inhibitors.

True but less relevant than implied.  They’re relying on a model of how SSRIs treat depression that is fairly outdated.  SSRIs definitely increase serotonin, it’s just that there’s no evidence that’s their mechanism of action against depression except that they do it and they treat depression.  “Depression is caused by a serotonin deficiency” is a lie simplification told to patients and their families to allay fear and shame around psychiatric treatment.  This doesn’t undercut their point that exercise is good for you, but does indicate this is not a great book to learn brain chemistry from.

Claim:  Both aerobic (prolonged moderate exercise such as running, cycling, or rowing over time) and anaerobic (like weight lifting or short sprinting) exercise have been found to be effective for decreasing depression, (Kindle Locations 239-241).

True. (Study 1 PDF) (Study 2 abstract).


Empirical Results

The theory behind this book is very well supported; the prescriptions it makes flow naturally from the theory, but the authors present no direct evidence that they work.  I’m torn about this.  I don’t want to engage in RCT worship; having a systemic understanding of a problem is even better than evidence a particular solution worked better or worse than another solution in a different population.  On the other hand, humans are very complicated and it’s easy to identify the problem but guess the wrong solution.

I couldn’t test any of this on myself because I already enjoy exercise for a lot of reasons, so I scrounged up an unscientific sample from my wider social network to try it.

14 people filled out the pre-book survey.  3 people filled out the post-attempt survey.  None of them exercised more.


The theory sections of this book are my high water mark for scientific rigor in a self-help-psych book.  I’m currently reading a lot of those with the goal of finding out how much rigor is reasonable to expect, so that’s high praise.

The book walks the very fine line between reassuring and condescending, which is pretty unavoidable with CBT and mindfulness.

I did not like the last chapter and recommend skipping it.  It feels like they tried to stuff all the usual diet-and-exercise stuff in at the end.  Some of my problem is I think their recommendations are wrong, and some is that I believe that even if they were correct, throwing them in at the last minute undercuts the message of the book.

The first part of this is that, in America, at least in certain subcultures, any mention of weight makes the whole thing About Weight.  Too many people use health or mood as a socially acceptable way to say “you’re not hot enough”, so any mention of weight in the context of diet or exercise automatically makes weight the real topic of the conversation.  If the improvements in mood are enough of a reason to exercise, let them be enough, and the weight loss can be a pleasant surprise or not happen, and both are okay because you got what you came for.

The authors compound this problem by using Body Mass Index as a guide for goal weight.  BMI is completely unsuited for use in individuals, even more so for people who just started gaining muscle mass.  If you must talk about fat in the context of health use body fat percentage or certain circumference ratios (e.g. wrist:stomach).

The second problem is the speed with which EFMaA tries to address nutrition.  The book (correctly) treats exercise as a thing that is challenging to start despite all its benefits, and spends 10 chapters explaining why it’s worth trying and providing scripts to make it workable for you, for the sole benefit of mood, ignoring everything else you might get out of exercise.  I don’t know why the authors thought that that required an entire book but the even more complicated of nutrition for every possible benefit of nutrition could be squeezed into half a chapter.  I would be have been very excited for another book by the same authors about how to implement healthy eating, but the half assed treatment here makes me pause.

They also present a particular diet as the settled science, when there is no such thing in nutrition.  “Eat produce and fish” is fairly uncontroversial, but they recommend a lot more refined grains than many other people.  I don’t know who is correct, but it was disappointing to see a book that had been so rigorous up to that point blithely paint over controversy.

[I have emailed Michael Otto about the handling of nutrition and have yet to hear back].

Speaking of which Exercise for Mood and Anxiety mentions that both aerobic (cardio) and anaeorbic (weights) are good for mood, but every single example is cardio, with an occasional cardio + core strength.

Mixed in through the book are tales of how Olympic athletes motivate themselves.  This feels spectacularly irrelevant to me.  I don’t want to win a gold medal, I want to climb V2s and be happy.

You might find this book valuable if:

  • You want some ideas (although not conclusive proof) around how exercise helps mood.
  • You want to want to exercise, and want scripts and tools to transform that into “want to exercise right now.”
  • You find exercise unpleasant and want to get the best trade of unpleasantness-for-benefits possible.
  • You would like to treat a mood issue with exercise (whether it reaches the level of official disorder or not).
  • You want to change how you think about exercise (for improving your mood or something else).
  • You are interested in CBT or mindfulness and want to practice with the large print version before tackling them directly.
  • You think you are different than my test audience.

You probably won’t find this book valuable if:

  • You already have an exercise program you are happy with.
  • You have body image or eating disorder issues (last chapter only, and a single section of the 10th,  the rest of it is fine).
  • You want prescriptions for a particular exercise program, as opposed to general principles.
  • You want to learn the nitty gritty of how exercise affects mood.
  • You are similar to my test audience.



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Epistemic Spot Check Changes

Previously I checked books pretty much as I went along.  Doing otherwise felt like the check was playacting; if knowing wasn’t going to affect my behavior towards the book it was rigor theater, not genuinely caring about a book’s factual accuracy.  I’m backing off on that.  It prevents a book from gathering any momentum and it’s too easy to turn into cheap shots. Instead, for the mental health books, my default is going to be read the introduction and at least one other chapter, marking what I want to verify as I go, and circle back at the end of the second chapter to fact check.  This will give the books a little time to breathe and for me to evaluate their model.  It’s also way easier for me.

The exception  will be books where I get a stuck feeling and need to look something up to continue, or where I get nerd sniped.

Epistemic Spot Check: A Guide To Better Movement (Todd Hargrove)

Edit 7/20/17: See comments from the author about this review.  In particular, he believes I overstated his claims, sometimes by a lot.


This is part of an ongoing series assessing where the epistemic bar should be for self-help books.


Thesis: increasing your physical capabilities is more often a matter of teaching your neurological system than it is anything to do with your body directly.  This includes things that really really look like they’re about physical constraints, like strength and flexibility.  You can treat injuries and pain and improve performance by working on the nervous system alone.  More surprising, treating these physical issues will have spillover effects, improving your mental and emotional health. A Guide To Better Movement provides both specific exercises for treating those issues and general principles that can be applied to any movement art or therapy.

The first chapter of this book failed spot checking pretty hard.  If I hadn’t had a very strong recommendation from a friend (“I didn’t take pain medication after two shoulder surgeries” strong), I would have tossed it aside.  But I’m glad I kept going, because it turned out to be quite valuable (this is what triggered that meta post on epistemic spot checking).  In accordance with the previous announcement on epistemic spot checking, I’m presenting the checks of chapter one (which failed, badly), and chapter six (which contains the best explanation of pain psychology I’ve ever seen), and a review of model quality.  I’m very eager for feedback on how this works for people.

Chapter 1: Intro (of the book)

Claim: “Although we might imagine we are lengthening muscle by stretching, it is more likely that increased range of motion is caused by changes in the nervous system’s tolerance to stretch, rather than actual length changes in muscles. ” (p. 5). 

Overstated, weak.  (PDF).  The paper’s claims to apply this up to 8 weeks, no further.  Additionally, the paper draws most (all?) of its data from two studies and it doesn’t give the sample size of either.

Claim:  “Research shows the forces required to deform mature connective tissue are probably impossible to create with hands, elbows or foam rollers.” (p. 5). 

Misleading. (Abstract).  Where by “research” the Hargrove means “mathematical model extrapolated from a single subject”.

Claim:  “in hockey players, strong adductors are far more protective against groin strain than flexible adductors, which offer no benefit” (p. 14).

Misleading. (Abstract) Sample size is small, and the study was of the relative strength of adductor to abductor, not absolute strength.

Claim: “Flexibility in the muscles of the posterior chain correlates with slower running and poor running economy.” (p. 14).

Accurate citation, weak study.  (Abstract) Sample size: 8.  Eight.  And it’s correlational.

[A number of interesting ideas whose citations are in books and thus inaccessible to me]

Claim:  “…most studies looking at measurable differences in posture between individuals find that such differences do not predict differences in chronic pain levels.”  (p. 31). 

Accurate citation.  (Abstract).  It’s a metastudy and I didn’t track down any of the 54 studies included, but the results are definitely quoted accurately.


Chapter 6: Pain

Claim: “Neuromatrix” approach to pain means the pattern of brain activity that create pain, and that pain is an output of brain activity, not an input (p93).

True, although the ability to correctly use definitions is not very impressive.

Claim: “If you think a particular stimulus will cause pain, then pain is more likely.  Cancer patients will feel more pain if they believe the pain heralds the return of cancer, rather than being a natural part of the healing process.” (p93).

Correctly cited, small sample size. (Source 1, source 2, TEDx Talk).

ClaimPsychological states associated with mood disorders (depression, anxiety, learned helplessness, etc) are associated with pain (p94).

True, (source), although it doesn’t look like the study is trying to establish causality.

ClaimMany pain-free people have the kinds of injuries doctors blame pain on (p95).

True, many sources, all with small sample sizes.  (source 1, source 2, source 3, source 4, source 5)

Claim: On taking some cure for pain, relief kicks in before the chemical has a chance to do any work (p98)

True.  His source for this was a little opaque but I’ve seen this fact validated many other places.

Claim: we know you can have pain without stimulus because you can have arm pain without an arm (p102).

True, phantom limb pain is well established.

Claim: some people feel a heart attack as arm pain because the nerves are very close to each other and the heart basically never hurts, so the brain “corrects” the signal to originating in the arm (p102).

First part: True.  Explanation: unsupported.  The explanation certainly makes sense, but he provides no citations and I can’t find any other source on it.

Claim: Inflammation lowers the firing threshold of nociceptors (aka sensitization) (p102).

True (source).

Claim: nociception is processed by the dorsal horn in the spine.  The dorsal horn can also become sensitized, firing with less stimulus than it otherwise would.  Constant activation is one of the things that increases sensitivity, which is one mechanism for chronic pain (p103).

True (source).

Claim: people with chronic pain often have poor “body maps”, meaning that their mental model of where they are in space is inaccurate and they have less resolution when assessing where a given sensation is coming from (p107).

Accurate citation (source).  This is a combination of literature review and reporting of novel results.  The novel results had a sample of five.

Claim: The hidden hand in the rubber hand illusion experiences a drop in temperature (p109).

Accurate citation, tiny sample size (source).  This paper, which is cited by the book’s citation, contains six experiments with sample sizes of fifteen or less.  I am torn between dismissing this because cool results with tiny sample sizes are usually bullshit, and accepting it because it is super cool.

Claim: “a hand that has been disowned through use of the rubber hand illusion will suffer more inflammation in response to a physical insult than a normal hand.” (p. 109).

Almost accurate citation (source).  The study was about histamine injection, not injury per se.   Insult technically covers both, but I would have preferred a more precise phrasing.  Also, sample size 34.

Claim: People with chronic back pain have trouble perceiving the outline of their back (p. 109). 

Accurate citation, sample size six (pdf).

Claim:  “Watching the movements in a mirror makes the movements less painful [for people with lower back pain].” (p. 111). Better Movement. Kindle Edition.

Accurate citation, small sample size (source).

Model Quality

Reminder: the model is that pain and exhaustion are a product of your brain processing a variety of information.  The prediction is that improving the quality of processing via the principles explained in the book can reduce pain and increase your physical capabilities.

Simplicity: Good.  This is not actually simple model, it requires a ton of explanation to a layman.  But most of its assumptions come from neurology as a whole; the leap from “more or less accepted facts about neurology” to this model is quite small.

Explanation Quality: Fantastic.  I’ve done some reading on pain psychology, much of which is consistent with Guide…, but Guide… has by far the best explanation I’ve read.

Explicit Predictions: Good, kept from greatness only by the fact that brains and bodies are both very complicated and there’s only so much even a very good model can do.

Useful Predictions: Okay. The testable prediction for the home-reader is that following the exercises in the back of the book, or going to a Feldenkrais class, will treat chronic pain, and increase flexibility and strength.  Since the book itself admits that a lot of things offer short term relief but don’t address the real problem, helping immediately doesn’t prove very much.

Acknowledging Limitations: low. (Note: author disputes this, and it’s entirely possible he did and I forgot).  GTBM doesn’t have the grandiose vision of some cure-all books, and repeatedly reminds you that your brain being involved doesn’t mean your brain is in control.  But there’s no sentence along the lines of “if this doesn’t work there’s a mechanical problem and you should see a doctor.”

Measurability: low.  This book expects you to put in a lot of time before seeing results, and does not make a specific prediction of the form they will come in.  Worse, I don’t think you can skip straight to the exercises.  If I hadn’t read the entire preceding book I wouldn’t have approached them in the correct spirit of attention and curiosity.

Hmmm, if I’d assigned a gestalt rating it would have been higher than what I now think is merited based on the subscores.  I deliberately wrote this mostly before trying the exercises, so I can’t give an effectiveness score.  If you do decide to try it, please let me know how it goes so I can further calibrate my reviews to actual effectiveness.


You might like this book if…

…you suffer from chronic pain or musculoskeletal issues, or find the mind-body connection fascinating.

This post supported by Patreon.

How to Handle Bad Examples in Texts?

How harshly should you judge when a scientific work gives a bad example of its point?

For example, I am reading Interaction Ritual Chains (Randall Collins), which focuses on emotional energy during stereotyped interactions between people (this is the scientific sense of stereotyped, meaning rigid or strongly patterned, not racist).  IRC believes that interaction is important and irreplaceable, such that people will shun much more “efficient” solutions to their official goal in order to get interpersonal interactions.  Unfortunately it uses terrible examples to illustrate this.

For example, on page 63 he claims that online shopping will never replace brick and mortar stores, because going to the store amidst other people is an energizing ritual.  At the time the book was published (2004) this was obviously untrue to me, but I can see how it wasn’t in every segment of society.  So while this is a bad prediction, it’s not a factual error.

He also claims that television has had no impact on sports attendance because people want the in person experience so much (p57).  To the extent that is true, it’s because leagues has gone to a great deal of trouble to make it not true, by imposing blackout rules such that you can’t broadcast a local game unless it has sold out.  It’s only since 1973 that the NFL had an exception for sold out games- previous to that, the only way to see a game played in your market was to be there.

How much should I reduce my confidence in Interaction Ritual Chains, given that it made this error? Or two false predictions?  Is it even fair to score them as false? In person stores still exist, although malls are having a hard time of it.  Maybe blackout rules were preemptive strikes and attendance would have stayed high without them.  But this gives me qualms about learning examples I know less about- even if the author is being accurate, if I’m drawing incorrect conclusions.

Epistemic Spot Check: The Demon Under the Microscope (Thomas Hager)


How much would it suck to be the guy who invented sulfa drugs? You dedicate your life to preventing a repeat of the horrors you saw in the war, succeed in that and so much more, and then 10 years later some idiot leaves a petri dish open and completely replaces you as the father of man’s triumph against bacteria.  Actually he left the lid off before you found your thing, but ignored the result until you hit it big because everyone knew you couldn’t fight disease with chemicals, until you proved you could.  It’s the ultimate silver medal.  The Demon Under the Microscope is the tale of that guy.

It’s by the same author (Thomas Hagen) as The Alchemy of Air.  It’s also set in the same corporation, and about field that was transforming from science to industry.  The writing style is similar.  I originally didn’t intend to fact check this book very hard because I already knew what to expect from the author (a little too invested in the subject but basically accurate), but the habit is too ingrained at this point and I couldn’t keep reading until I’d checked out the first few chapters.



Claim: “Domagk [the researcher] had the ability to see. He watched everything, noted slight variations, quietly filed it all away.”  (p. 18).

The wounds themselves he accepted as the results of war. But the infections that followed—surely science could do something to stop those. He focused on the bacteria, his personal demons, “these terrible enemies of man that murder him maliciously and treacherously without giving him a chance.” “I swore before God and myself,” he later wrote, “to counter this destructive madness.”  (p. 20).

Who knows but it’s pretty.  Someone in the same position as thousands of others (in this case a WW1 medic), caring more , and going to fix it (via sulfa drugs) is my moral aesthetic.  Of course there could be another surgeon in the same place with just as much care and potential who got blow up or gassed.  The Alchemy of Air prioritized poetry over provability, so I don’t entirely trust this, but I like it.

Claim: Cholera was a big problem for German soldiers.

This would be a weird thing to make up, but I’m a little confused.  There had been a cholera vaccine for over 20 years by that point.

Claim: Gas gangrene is bad.


Claim: Sir Almroth Wright created a typhoid vaccine that was deployed during WW1, saving may lives.  During WW1 he established a laboratory researching wound infections.

True.  He was also prescient enough to foresee the risk of drug-resistant bacteria.  Of course he also thought that bacteria were associated with but not the cause of disease, and that scurvy was caused by poorly preserved meat.  Being right is hard.

Claim: Doctors at the time thought that a dry wound was more resistant to infection; however dryness inhibited white blood cells and thus ultimately increased infections. They also thought wounds needed to be completely covered to prevent reinfection, but this created the ideal environment for anaerobic bacteria like Clostridium perfringens (which causes gas gangrene).

True. I was surprised to find ideal wound moistness still isn’t entirely settled, but the book’s description seems essentially in good faith.  Demon goes on to say that by the 1920s, doctors believed they were basically powerless and their job was to get the body’s own healing systems a pillow and some tea.  They took this so far that:

“A physician doing drug research was a physician taken away from patient care. There was an unsavory aspect to a physician’s developing a drug for money. There were ethical questions about testing drugs on patients. Developing new drug therapies smacked of a return to the discredited age of bleedings and purgings.”


To repeat: researching new treatments was considered distasteful at best and morally outrageous at worst.  And brain differentiation was once considered phrenology redux.  I just don’t think we’re very good at seeing where medicine is going (p40).

Claim: Section on Leeuwenhoek. 

True but missing time data.  Given that everything discussed so far happened in the range of 1890-1920, I would have have explicitly mentioned I was going 250 years into the past.  As it was, the only reason I noticed was that I recognized some of the names on the list of Leeuwenhoek’s contemporaries. The kindle edition may have made this worse.   But everything Hager actually says on Leeuwenhoek’s work in inventing the microscope seems accurate.

Claim: [crickets] (no page)

There’s no false statements, but I found the absence of discussion of the 1918 Spanish Flu epidemic puzzling.  Demon’s narrative is that seeing the horror of infected wounds in World War 1 drove Domangk to dedicate his life to preventing them.  Spanish Flu killed 5% of the entire world over the course of three years, and had a massive effect on troop movements and training in WW1.  From a military perspective it might have been more important.  We know now that the flu is really hard to vaccinate against, but at the time they didn’t even know it was a virus.  If you were a motivated medic looking for something to care about, Spanish Flu was a really obvious choice.  Demon mentions Spanish Flu in passing but not as an influence on Domangk, and that feels incomplete to me. Why gangrene in particular, when there were so many horrors happening at the time?

Claim: Streptococcus is the cause of everything bad.

True.  I knew it was possible to die from a scratch, but reading about everything strep causes really made me appreciate how few technological innovations are between us humans and mass die offs.  Strep causes childbed fever, St. Anthony’s Fire, meningitis, scarlet fever, pink eye, necrotizing fasciitis… Strep is the cockroach of human-infecting bacteria.  And for a while, all we had to do was take a pill and it was completely harmless.

Of course now we have MRSA (Methicillin-resistant Staphylococcus aureus) (whose natural habitat is the hospital, just like strep).  And multiply resistant gonorrhea.  And tuberculosis resistant to most known antibiotics.  The bad old days are on our heels, is what I’m saying.

One weird thing is I finished this book with the vague impression that sulfa drugs had saved a lot of lives but not actually knowing how many.  This article estimates that sulfa drugs led to a 2-3% drop in overall mortality, which translated to a 0.4-0.7 year increase in life expectancy.  That only covers up until 1943: presumably it had a bigger impact as distribution increased, or at least would have if penicillin had not taken over.

Overall Verdict

Pretty good, with some oversights.  Like Alchemy of Air the beginning is the best part, and if you find your attention flagging I’d just let it go.  I found the subject matter more innately interesting than Alchemy of Air but the writing a little less so.  Demon spends less time on the personal lives of the scientists, which was a selling point for my roommate but a disappointment for me.

This post supported by Patreon.

Epistemic Spot Check Update

I am really enjoying this project and plan on continuing.  I have started a subproject of reading self-help-ish books that claim scientific validity, to determine what the correct standard of science is for them.  Some books have clearly failed this (looking at you, Upward Spiral).  Some have had very accurate citations and strong evidence for the problem they are solving, but their prescriptions have not actually been tested (Exercise for Mood and Anxiety). Others have wrong or weak evidence, and yet the prescriptions have been very helpful to me or people I know.  It would a great loss to throw those out, but we can’t read every self help book just to see what works.

My solution is to create a new axis for epistemic spot checks: model quality.  A high quality model has the following characteristics:

  • As simple as possible, but no simpler.
  • Explained well in the book (you should be able to teach it afterwords)
  • Makes explicit predictions that are testable on a reasonable timescale.  Ideally the predictions are novel or counterintuitive.
  • Recognizes that the technique may not work and explicitly talks about when that might happen, how to recognize it, and what to do.
  • Usefulness

How do these strike people?  Are there other criteria you would want information on? Other thoughts?

Epistemic Spot Check: The Alchemy of Air (Thomas Hager)

[content warning: war, the Holocaust]


Fixed nitrogen is a startlingly important molecule, essential in both explosives and farming. Until the 1900s, turning atmospheric nitrogen (which is abundant) into fixed nitrogen was the purview of a handful of bacteria, and countries went to great length to get more.  Several wars were fought and decided over/by who had better access to nitrogen stores.

In the early 1900s, German scientist Fritz Haber invented (and engineer Carl Bosch industrialized) a process for producing fixed nitrogen.  This changed the world on a number of levels:

  • Removed the nitrogen-induced cap on the human population, which was ~4 billion people.  You know how people say it’s impossible for everyone to eat organic?  This is why.  There is not nearly enough natural fixed nitrogen to feed everyone.
  • Prolonged Germany’s involvement in World War 1 by one to two years, by both increasing the volume of explosives they had access to and by making it possible to feed people from relatively poor farmland.
  • Was part of a larger shift in Germany becoming an economic and scientific power.

The Alchemy of Air starts with a longer description of why fixed nitrogen is so important.  The meat of the book  is the invention of the Haber-Bosch process and the life stories of the two men responsible for it.  It touches on the chemistry of nitrogen, how a proof of concept becomes and industrial process at the age when those were beginning to separate.  At the end, it offers a glimpse into the rise of Hitler and the Nazi party as viewed by the scientific community.

Fact Checking

Claims: “Nitrogen is the most important element… for humans”, “more interesting than other elements.”  “Nitrogen is a/the rate limiting factor in life on Earth.  If you put more fixed nitrogen in a field, you can grow more.” (Prologue).

True-ish. I don’t know how to fact check which element is more interesting.  I went through 7 semesters of college chemistry without picking a favorite element.  But the more factual claim that nitrogen is a major limitation of growth on life on Earth checks out.  The other major elements we need- carbon, oxygen, and hydrogen- are relatively cheap to create from molecules found in the air (although oxygen is the limiting factor in certain aquatic ecosystems- and as you learn at the end of the book, fixed nitrogen abundance makes this worse).    Atmospheric nitrogen makes up 80% of the air, but it is incredibly energetically expensive to convert that into nitrogen useful to plants and animals (known as fixed nitrogen)

Claim: “N2 is [harder to break down because it is] held together with a triple bond, the strongest bond in nature.” (prologue)

True but incomplete. Nitrogen does use a triple bond.  On average, triple bonds will be more expensive to break or form than double or single bonds.  But carbon can form four bonds.  You can’t actually have a stable quadruple bonds because of complicated shape things, but they can triple bond with each other and each have a side chain.  It’s possible HCCH is just as expensive to break apart, but there’s enough carbon in easily accessible forms that it doesn’t matter.

Also, the fact that N2 (the kind of nitrogen found in the atmosphere) is expensive to break doesn’t explain why fixed nitrogen makes such an excellent explosive.  The fact that it is implies that fixed nitrogen is also energetically expensive to make.  The internet is rather lacking on this topic, but the fact that fixation is net negative on ATP (the energy currency of living things) suggests that I’m right.  “This bond stores a lot of energy” is not actually a good argument for why no one breaks it.

Claim: “Using [their complicated farming system involving three different animals and five different types of plants], the Chinese could feed as many as ten people per acre of farmland, a yield of food five to ten times greater than the European average of the 1800s” (p5)

True but misleading. Verifying this is surprisingly hard, but I do know that Chinese agriculture was incredibly labor intensive, much more so than European farming.  That’s why 1800s China has a bunch of proverbs about working hard and Europe had a bunch of proverbs about hoping it rained (source, although I’d like to do a fact check on this one).

Claim: Haber-Bosch uses 1% of the Earth’s energy (p271)

True, although this refers only to generated energy and not natural sources like the sun or underwater vents.

Claim: “Half the nitrogen in your blood, your skin and hair, your proteins and DNA, is synthetic” (p272)

False.  The atom was nitrogen when you found it and it’s nitrogen now.  The molecule that delivered it to the plant was synthetically produced, but the nitrogen has always been itself.  At a minimum, synthetic should mean you found different atoms and combined them into something new, but chemistry has an even stricter definition: elements that do not exist naturally and must be created in a lab.

Claim: “Nitrogen pollution in the water has been to linked to health problems like methemoglobinemia, or “blue baby syndrome”” (p274)

True.  The EPA supports this, although it appears there’s still some scientific controversy over exactly how large a role nitrogen plays.

Claim: Nitrogen run off causes algal blooms that devastate aquatic ecosystems (p274)


Claim: A long history of saltpeter I’m not going to transcribe fact-by-fact (chapter 1)

True.  I didn’t run down every fact but everything I could find checked out, and his conclusions (saltpeter was incredibly valuable) are supported by other information he didn’t mention.

Claim: Darwin was hired onto the Beagle as someone of suitable social stature for the captain to talk to so he didn’t go mad.


Claim: After saltpeter, bird shit became the coveted resource (chapter 3)

True. Again, I didn’t run down every single thing, but guano was the immediate catalyst for the South American colonies to revolt against the Spanish, the USA still has a law on the books allowing any citizen to claim guano rich islands for the country.

Other thoughts

Alchemy of Air is a weirdly uneven book.  I don’t think this is writing style, I think it’s just covering a lot of different material and what people find interesting varies a lot.  For example, I loved the sections on the history and economics of nitrogen, and how the Haber-Bosch industrial process for producing fixed nitrogen from the air affected World War 1.  The fourty three chapters on Bosch taking Haber’s proof of concept to a scalable industrial process?  Do not care.  Almost quit book until I remembered I could just skip them.

The parts on the personal lives of Bosch and Haber were very mixed bag.  Mostly boring, but intricately involved with the extremely interesting things that were happening at the time (~1900 to the rise of the Nazis).  Fritz Haber was a German Jew who merged love of science with love of country in his mind, and converted to Christianity in part so he could be viewed as more fully German.  The Haber-Bosch process probably bought Germany another year in World War 1, probably two.  He played a major role in inventing chemical warfare (Alchemy would have you believe he invented it, but is prone to exaggeration).  You can guess how this ends.  In 1934 he flees the country, made more difficult by the fact that the rest of the world still considers him a German war criminal.  The chemical he invented for use on Allied soldiers in WW1 is adapted for use in the concentration gas chambers in WW2.

Bosch’s life is also complicated.  Between the wars he dedicated everything he had and then some to inventing a way to synthesize gasoline.  This included collaborating with the early Nazi party for funding.  They were happy to do so because they, correctly, anticipated that an internal source of gas would be necessary in the upcoming war.  At some point Bosch realized what he’d done, made a bunch of symbolic gestures against the Nazis, and died in disgrace.  It’s weird because those symbolic gestures probably cost him a lot and accomplished nothing, whereas there’s some chance he could have prevented WW2 and the entire Holocaust by not working quite so hard to create synthetic gasoline.  By the time the Nazis were in power it might have bankrupted his company to stop, but it was still doable.  Maybe someone else would have invented synthetic gas… but Bosch’s company was uniquely well positioned to do so, and he basically willed it into existence by convincing an increasingly large collection of people to toss money at the process.  He didn’t even have to give up, he just had to try less hard on fundraising.

And of course both men have saved/enabled billions of lives by creating the process that feeds them.

I don’t know what to do with this information.  The world is complicated and I want the right thing to be obvious.


Generally reliable, moderately stylized.  I trust the author for broad strokes but not to give me non-nitrogen related nuance.

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Epistemic Spot Check: A Brief History of the Human Race (Michael Cook)

I was worried my epistemic spot checking project was doomed before it began.  The well regarded Sapiens dismissed a link between cultural and genetic evolution, and Last Ape Standing made two explosively wrong errors in the first chapter.  Neither related to human evolution (one was about modern extreme poverty and the other about cetacean evolution), but I just couldn’t let them go.  I worried that every book was terrible if you actually fact checked it, or maybe just every book on the emergence of homonids?

And then I started A Brief History of the Human Race.  Two chapters in, I cannot find a flaw in it.  There are a few simplifications, and some broad statements he later walks back, but nothing I can point to and say “that is miseducating people.”  Meanwhile there are a lot of things I can point to and say “that is right”, even things I initially thought were wrong.  So I think A Brief History… might be the one.

Here’s a list of statements I checked and their results.  Normally I sort claims into true and untrue sections, but that proved unnecessary in this case because it is a beautiful rigorous snowflake of a book.

Claim: The holocene era has had unusual climactic stability, and is warmer than typical for the planet (page 6).
This checks out, but it’s a little weird that his graph doesn’t label the temperature axes, and it’s a graph of oxygen ratios from a single glacier rather than the wider variety of evidence available.
Cook further claims that this warmth and stability is what let farming, and thus history, start.   There’s some counter evidence to the claim of the holocene as the absolute start of agriculture. but it certainly seems legitimate to say that’s when it really took off.
Claim: there exists art “well over 20,000 years old” (page 9)
I was very surprised by this but if anything he’s underselling it; there’s claims of 50,000 year old art 
Claim: most human DNA is junk DNA that serves no purpose, and mutations have no effect (page 11):
He’s a little behind the times on junk DNA. Even when A Brief History… was published (2003) we knew it that while lots of DNA didn’t encode any proteins, much of it does seem to serve some purpose and mutations in it are significant.  At a minimum noncoding DNA definitely plays a role in the regulation of DNA transcription, the structural cohesion of the chromosome, and protecting coding DNA from degradation.  This is the closest thing to a falsehood I found in the first two chapters.  At the level of genetics this book is discussing I think it’s a forgivable simplification, although an addendum noting the real world was more complicated would have been appreciated.
Claim: humans are inbred (page 12)
Very true.
Page 13: AFAIK this explanation of multiorigin vs out of Africa human evolution hypotheses is correct, and he’s picked the correct winner.
Claim: evidence of human tool use half a million years ago (page 16)
me: there is no way there were tools that long ago.
internet: yes there is.
Claim: early hominid and chimp tool use are both culturally transmitted (page 17)
I’m pretty sure this is correct, and I appreciate the distinction he is making
Claim: it was hard for nomadic hominids to combine their tools in novel ways, because they had so little room. There are exceptions, but they might have been better off sticking with lower technology (page 20).
I am extremely happy to see this guy acknowledge that hunter gatherers had a pretty kick ass life and farming sucked.
Claim: iron is more abundant than copper because of something about supernovas (page 29).
Claim: cattle domesticated multiple times (page 30).
Claim: humans adapt to domesticated animals culturally but not genetically (page 32).
This ignores the co-domestication of humans and wolves but is basically true for everything else.
Claim: humans did not genetically adapt to farming (page 33).
me: ehhhhh….lactose tolerance was a pretty big deal.
p34: exceptions: lactose tolerance and disease resistance.
me: I accept your apology.
Claim: Maori had and then lost the technique for pottery (p36).
Not only is A Brief History… not saying wrong things, it is throwing out tangential facts at about the right rate.  I was never going to look up which molecules supernovas produced.  But now I have a general idea of the concept of “primary elements” and how this affected human history, which makes me happy.
Verdict: A Brief History of the Human Race has passed the epistemic spot check with flying colors, and is enjoyable to read.
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Epistemic Spot Check: Sapiens (Yuval Noah Harari)

Usually I try to write full reviews and only on things I recommend, because take downs are easy and there’s enough negativity in the world.  But a few people on facebook expressed interest in having me factcheck early chapters in books, so they could know what was worth trying.  This is my test of that.  Please let me know what you find useful and not useful about the formatting or information here.

How this worked:  I listened to Sapiens.  When he said something interesting, counterintuitive, or that conflicted with other information I had, I looked it up.  In this post I’ve detailed the claims he made and what my investigation revealed, regardless of who was right.  I’ve also included some correct claims I didn’t need to look up because it’s important to talk about what people get right, and because it changes the way I read the book for the better.

I realize page numbers would be very helpful here, but I’m listening to this on tape so no dice.

False Claims

Claim: humanity’s big break was using tools to access bone marrow from carcasses left behind by lions and hyenas (in that order).  

Marrow is a fantastic source of calories and micronutrients, so this would certainly be a good way for an expensive brain to pay rent.  But I have two problems with this explanation.  One is that we’ve known for decades that lions steal from hyenas much more than the reverse.  Repeating the trope that lions are majestic predators and hyenas dirty scavengers is just lazy.  My second problem is that hyenas can eat bones.  And none of this pansy using a tool to extract the fat nonsense.  They put a bone in their mouth and chew.  Eating marrow after hyenas pick over the carcass is not a viable plan.  There are lots of other ways sapiens could still have made bone scavenging work for them, like working between the lions and the hyenas.  But this is starting to sound much more like a nature show fairy tale than science.

There is a strong school of thought that humans did in fact start as scavengers, although no one can decide if they were the scavengers of last resort, or if social coordination let them push lions off their own kills (PDF).  Personally I’m partial to the endurance hunter hypothesis, but they’re not mutually exclusive and interestingness is not a good predictor of truth.

Claim: Dunbar’s Number, both the value and what happens when you exceed it, is settled science.

I didn’t actually research this one, but nothing in sociology is as settled as he presents this to be.

Claim: Humans are the only animals that have cultural evolution independent of genetic evolution.

This is not true.  There are many documented reports of social transmission of new tool use and behavior  within monkey troops.  Not to mention persistent communication and behavioral differences between primate and cetacean social groups.

I will freely admit that humans are in a league of their own when it comes to cooperative tool design and use, but that’s not what Harari said.  He denied all cultural transmission of ideas among all other animals.

Tenuous Claims

Claim: something overly poetic about the ascendency of man 

“the world had time to adjust to lions becoming awesome.  Humanity became an apex predator so quickly the world didn’t have time to adjust.  Humans themselves didn’t have time to adjust.  “…Sapiens, by contrast, is more like a banana republic dictator.  Having so recently been the underdog of the Savannah, we are full of fears and anxieties over our position, which makes us doubly cruel and dangerous.  Many historical calamities, from deadly wars to ecological catastrophes, have resulted from this overhasty jump.”

My first instinct was that this is not even wrong enough to investigate.  On the other hand, approximately 104% of my friends have anxiety disorders- could that be because we didn’t have time to evolve out of our fear of predation?  A fairly well accepted but hard to test hypothesis is that a lot of modern human problems come from a mismatch between a stress system meant to handle predation and the problems we’re exposed to now.  Cortisol, the longer lasting of the stress hormones, increases heart and breathing rate, and inflammation, and decreases energy sent to digestion and the long term immune system.  This is a great trade if you are running from a tiger; the increased blood flow and heavy breathing send more oxygen to your muscles, which facilitates running the fuck away.  The inflammation increases the rate at which wounds close.  Your sleep will be lighter so you’ll hear the tiger coming.  Difficulty digesting and fighting parasites is irrelevant if you’re dead, so who cares?  But if the problem is, say, you work in an unstable industry and are constantly afraid of being fired, cortisol is not very helpful.  Sleep deprivation will muddle your thinking.  You’ll get sick more and get fewer nutrients.  And inflammation is responsible for approximately everything bad, so good luck with that.

So there is a sense in which the original statement is close enough for poetry’s sake.   And in one sense it’s tautologically true that if the world had time to adjust to our evolution we wouldn’t cause quite so many ecological dumpster fires.  But framing this as some sort of Napolean syndrome seems suspect to me.  We are so secure in our superiority over lions we get sad when you kill our favorites.  We have a whole week dedicated to celebrating 400 million year old killing machines in the one niche we don’t dominate.

So this claim is a little too gaia-worship to me, but not actually wrong.

True Claims

Claim: Humans are the only animal that barter.  

I thought this was wrong, but it turns out to be correct.  The closest thing to an exception is chimpanzees, who will trade food for sex, but it seems more like a gift economy.   They can be trained to trade food products in a lab, but even with extensive training will do so only reluctantly.  Neither of these impugn the point.

Claim: The development of cooking opened up early humans’ options.

It rendered undigestible foods digestible, made all foods take less energy to digest, and killed pathogens, letting us invest less in our immune system (especially important if any of the scavenger hypotheses are true).

Claim: intelligence and walking upright combine poorly.

A combination of larger heads and the pelvic changes required to walk upright were hell on women, leading to human babies being born underdeveloped and a higher maternal death rate in childbirth.

Slightly suspect: comparisons of the abilities of human neonates to gazelle neonates.  Prey animals are always born more developed than predator animals because your parents can hunt for you in a way they can’t run from predators for you.  Harari also makes the much more valid comparison to tiger kittens, and the point isn’t wrong; human infants are shockingly undeveloped for placental mammals.  But including the gazelles is pointlessly misleading.

Claim: Homo sapien mostly killed other homo species but did interbreed with them a little

DNA analysis shows that Europeans have small amounts of neathanderthal DNA and east asians have small amounts of denisovan DNA.

Claim: The word Homo in Homo sapien means “man” or “human” in Latin.

I was going to get really snotty about this, because everyone knows homo means same.  Turns out that’s what it means in Greek.   In Latin Homo does in fact mean “human.”  Touche, book.

You Lost Me At…

Timestamp 1:18 (out of 14:04)

This is where Harari lays out his thesis: humans ability to create universally agreed upon abstractions like gods, laws, and corporations is the thing that led us to create civilization.

This sounds plausible and I would like to hear more.  However I get the distinct impression he thinks cultural evolution is opposite or at least orthogonal to biological evolution, as opposed to a tool of it.  He uses Catholic priests and Buddhist monks as examples of people driven by cultural forces to take paths that are obviously evolutionary dead ends.  I know more about the Catholic Church than I do about Buddhist monks so that’s talk about that .

The most obvious flaw: taking a vow of celibacy is not the same as being celibate.    Hard number for low ranking priests are hard to find, but please enjoy this list of sexually active popes.  Additionally, the reason I struggled to find accurate numbers on medieval priests is that the google results were dominated by the modern Church’s sexual abuse scandals.

Next, not having children is not the same as being an evolutionary dead end.   Naive group selection is not a thing, but kin selection totally is.  Being a local priest and putting your thumb on the scale in favor of your nephews is a perfectly viable evolutionary strategy.

Third, he asserts that myths such as Catholicism drive people to actions independent of environmental conditions.  This is not true.  As societal wealth rises (and nobles no longer need someone safe to stash third sons) the Catholic Church has had a harder and harder time finding people willing to take vows.  They increasingly rely on unordained deacons and priests from third world countries.

Culture can definitely induce changes that are counter to one’s genetic interests.  But that’s an accident, the same way that cancer is an accident.  The interesting thing is how biological evolution created a platform through which cultural evolution could serve our biological interests (on average).

For a while I worried I was being uncharitable because he wasn’t paying sufficient respect to my pet subject.  This doubt went away at 1:18, when he said “The cognitive revolution is accordingly the point when history declared its independence from biology.”  He does walk this back a little, but some things can’t be unsaid.


A couple of sloppy simplifications that aren’t deal breakers but do lower the value of the author’s word.

Author’s understanding of evolution too weak for me to want to hear more.  Sometimes I like seeing other people’s models of the world even if they’re not literally true, but explaining culture without genetics feels completely unmoored to me.