The Human Mind

Book review: Into the Gray Zone: A Neuroscientist Explores the Border Between Life and Death, by Adrian Owen.

Too many books and talks have gratuitous displays of fMRIs and neuroscience. At last, here’s a book where fMRIs are used with fairly good reason, and neuroscience is explained only when that’s appropriate.

Owen provides evidence of near-normal brain activity in a modest fraction of people who had been classified as being in a persistent vegetative state. They are capable of answering yes or no to most questions, and show signs of understanding the plots of movies.

Owen believes this evidence is enough to say they’re conscious. I suspect he’s mostly right about that, and that they do experience much of the brain function that is typically associated with consciousness. Owen doesn’t have any special insights into what we mean by the word consciousness. He mostly just investigates how to distinguish between near-normal mental activity and seriously impaired mental activity.

So what were neurologists previously using to classify people as vegetative? As far as I can tell, they were diagnosing based on a lack of motor responses, even though they were aware of an alternate diagnosis, total locked-in syndrome, with identical symptoms. Locked-in syndrome and persistent vegetative state were both coined (in part) by the same person (but I’m unclear who coined the term total locked-in syndrome).

My guess is that the diagnoses have been influenced by a need for certainty. (whose need? family members? doctors? It’s not obvious).

The book has a bunch of mostly unremarkable comments about ethics. But I was impressed by Owen’s observation that people misjudge whether they’d want to die if they end up in a locked-in state. So how likely is it they’ll mispredict what they’d want in other similar conditions? I should have deduced this from the book stumbling on happiness, but I failed to think about it.

I’m a bit disturbed by Owen’s claim that late-stage Alzheimer’s patients have no sense of self. He doesn’t cite evidence for this conclusion, and his research should hint to him that it would be quite hard to get good evidence on this subject.

Most books written by scientists who made interesting discoveries attribute the author’s success to their competence. This book provides clear evidence for the accidental nature of at least some science. Owen could easily have gotten no signs of consciousness from the first few patients he scanned. Given the effort needed for the scans, I can imagine that that would have resulted in a mistaken consensus of experts that vegetative states were being diagnosed correctly.

Book review: Darwin’s Unfinished Symphony: How Culture Made the Human Mind, by Kevin N. Laland.

This book is a mostly good complement to Henrich’s The Secret of our Success. The two books provide different, but strongly overlapping, perspectives on how cultural transmission of information played a key role in the evolution of human intelligence.

The first half of the book describes the importance of copying behavior in many animals.

I was a bit surprised that animals as simple as fruit flies are able to copy some behaviors of other fruit flies. Laland provides good evidence that a wide variety of species have evolved some ability to copy behavior, and that ability is strongly connected to the benefits of acquiring knowledge from others and the costs of alternative ways of acquiring that knowledge.

Yet I was also surprised that the value of copying is strongly limited by the low reliability with which behavior is copied, except with humans. Laland makes plausible claims that the need for high-fidelity copying of behavior was an important driving force behind the evolution of bigger and more sophisticated brains.

Laland claims that humans have a unique ability to teach, and that teaching is an important adaptation. He means teaching in a much broader sense than we see in schooling – he includes basic stuff that could have preceded language, such as a parent directing a child’s attention to things that the child ought to learn. This seems like a good extension to Henrich’s ideas.

The most interesting chapter theorizes about the origin of human language. Laland’s theory that language evolved for teaching provides maybe a bit stronger selection pressure than other theories, but he doesn’t provide much reason to reject competing theories.

Laland presents seven criteria for a good explanation of the evolution of language. But these criteria look somewhat biased toward his theory.

Laland’s first two criteria are that language should have been initially honest and cooperative. He implies that it must have been more honest and cooperative than modern language use is, but he isn’t as clear about that as I would like. Those two criteria seem designed as arguments against the theory that language evolved to impress potential mates. The mate-selection theory involves plenty of competition, and presumably a fair amount of deception. But better communicators do convey important evidence about the quality of their genes, even if they’re engaging in some deception. That seems sufficient to drive the evolution of language via mate-selection pressures.

Laland’s theory seems to provide a somewhat better explanation of when language evolved than most other theories do, so I’m inclined to treat it as one of the top theories. But I don’t expect any consensus on this topic anytime soon.

The book’s final four chapters seemed much less interesting. I recommend skipping them.

Henrich’s book emphasized evidence that humans are pretty similar to other apes. Laland emphasizes ways in which humans are unique (language and teaching ability). I didn’t notice any cases where they directly contradicted each other, but it’s a bit disturbing that they left quite different impressions while saying mostly appropriate things.

Henrich claimed that increasing climate variability created increased rewards for the fast adaptation that culture enabled. Laland disagrees, saying that cultural change itself is a more plausible explanation for the kind of environmental change that incentivized faster adaptation. My intuition says that Laland’s conclusion is correct, but he seems a bit overconfident about it.

Overall, Laland’s book is less comprehensive and less impressive than Henrich’s book, but is still good enough to be in my top ten list of books on the evolution of intelligence.

Update on 2017-08-18: I just read another theory about the evolution of language which directly contradicts Laland’s claim that early language needed to be honest and cooperative. Wild Voices: Mimicry, Reversal, Metaphor, and the Emergence of Language claims that an important role of initial human vocal flexibility was to deceive other species.

Book review: The Hungry Brain: Outsmarting the Instincts That Make Us Overeat, by Stephan Guyenet.

Researchers who studied obesity in rats used to have trouble coaxing their rats to overeat. The obvious approaches (a high fat diet, or a high sugar diet) were annoyingly slow. Then they stumbled on the approach of feeding human junk food to the rats, and made much faster progress.

What makes something “junk food”? The best parts of this book help to answer this, although some ambiguity remains. It mostly boils down to palatability (is it yummier than what our ancestors evolved to expect? If so, it’s somewhat addictive) and caloric density.

Presumably designers of popular snack foods have more sophisticated explanations of what makes people obese, since that’s apparently identical to what they’re paid to optimize (with maybe a few exceptions, such as snacks that are marketed as healthy or ethical). Yet researchers who officially study obesity seem reluctant to learn from snack food experts. (Because they’re the enemy? Because they’re low status? Because they work for evil corporations? Your guess is likely as good as mine.)

Guyenet provides fairly convincing evidence that it’s simple to achieve a healthy weight while feeling full. (E.g. the 20 potatoes a day diet). To the extent that we need willpower, it’s to avoid buying convenient/addictive food, and to avoid restaurants.

My experience is that I need a moderate amount of willpower to follow Guyenet’s diet ideas, and that it would require large amount of willpower if I attended many social events involving food. But for full control over my weight, it seemed like I needed to supplement a decent diet with some form of intermittent fasting (e.g. alternate day calorie restriction); Guyenet says little about that.

Guyenet’s practical advice boils down to a few simple rules: eat whole foods that resemble what our ancestors ate; don’t have other “food” anywhere that you can quickly grab it; sleep well; exercise; avoid stress. That’s sufficiently similar to advice I’ve heard before that I’m confident The Hungry Brain won’t revolutionize many people’s understanding of obesity. But it’s got a pretty good ratio of wisdom to questionable advice, and I’m unaware of reasons to expect much more than that.

Guyenet talks a lot about neuroscience. That would make sense if readers wanted to learn how to fix obesity via brain surgery. The book suggests that, in the absence of ethical constraints, it might be relatively easy to cure obesity by brain surgery. Yet I doubt such a solution would become popular, even given optimistic assumptions about safety.

An alternate explanation is that Guyenet is showing off his knowledge of brains, in order to show that he’s smart enough to have trustworthy beliefs about diets. But that effect is likely small, due to competition among diet-mongers for comparable displays of smartness.

Or maybe he’s trying to combat dualism, in order to ridicule the “just use willpower” approach to diet? Whatever the reason is, the focus on neuroscience implies something unimpressive about the target audience.

You should read this book if you eat a fairly healthy diet but are still overweight. Otherwise, read Guyenet’s blog instead, for a wider variety of health advice.

Book review: Daring Greatly: How the Courage to Be Vulnerable Transforms the Way We Live, Love, Parent, and Lead, by Brene Brown.

I almost didn’t read this because I was unimpressed by the TEDx video version of it, but parts of the book were pretty good (mainly chapters 3 and 4).

The book helped clarify my understanding of shame: how it differs from guilt, how it often constrains us without accomplishing anything useful, and how to reduce it.

She emphasizes that we can reduce shame by writing down or talking about shameful thoughts. She doesn’t give a strong explanation of what would cause that effect, but she prompted me to generate one: parts of my subconscious mind initially want to hide the shameful thoughts, and that causes them to fight the parts of my mind that want to generate interesting ideas. The act of communicating those ideas to the outside world convinces those censor-like parts of my mind to worry less about the ideas (because it’s too late? or because the social response is evidence that the censor was mistakenly worried? I don’t know).

I was a bit confused by her use of the phrase “scarcity culture”. I was initially tempted to imagine she wanted us to take a Panglossian view in which we ignore the resource constraints that keep us from eliminating poverty. But the context suggests she’s thinking more along the lines of “a culture of envy”. Or maybe a combination of perfectionism plus status seeking? Her related phrase “never enough” makes sense if I interpret it as “never impressive enough”.

I find it hard to distinguish those “bad” attitudes from the attitudes that seem important for me to strive for self-improvement.

She attempts to explain that distinction in a section on perfectionism. She compares perfectionism to healthy striving by noting that perfectionism focuses on what other people will think of us, whereas healthy striving is self-focused. Yet I’m pretty sure I’ve managed to hurt myself with perfectionism while focusing mostly on worries about how I’ll judge myself.

I suspect that healthy striving requires more focus on the benefits of success, and less attention to fear of failure, than is typical of perfectionism. The book hints at this, but doesn’t say it clearly when talking about perfectionism. Maybe she describes perfectionism better in her book The Gifts of Imperfection. Should I read that?

Her claim “When we stop caring about what people think, we lose our capacity for connection” feels important, and an area where I have trouble.

The book devotes too much attention to gender-stereotypical problems with shame. Those stereotypes are starting to look outdated. And it shouldn’t require two whole chapters to say that advice on how to have healthy interactions with people should also apply to relations at work, and to relations between parents and children.

The book was fairly easy to read, and parts of it are worth rereading.

Book review: The Measure of All Minds: Evaluating Natural and Artificial Intelligence, by José Hernández-Orallo.

Much of this book consists of surveys of the psychometric literature. But the best parts of the book involve original results that bring more rigor and generality to the field. The best parts of the book approach the quality that I saw in Judea Pearl’s Causality, and E.T. Jaynes’ Probability Theory, but Measure of All Minds achieves a smaller fraction of its author’s ambitions, and is sometimes poorly focused.

Hernández-Orallo has an impressive ambition: measure intelligence for any agent. The book mentions a wide variety of agents, such as normal humans, infants, deaf-blind humans, human teams, dogs, bacteria, Q-learning algorithms, etc.

The book is aimed at a narrow and fairly unusual target audience. Much of it reads like it’s directed at psychology researchers, but the more original parts of the book require thinking like a mathematician.

The survey part seems pretty comprehensive, but I wasn’t satisfied with his ability to distinguish the valuable parts (although he did a good job of ignoring the politicized rants that plague many discussions of this subject).

For nearly the first 200 pages of the book, I was mostly wondering whether the book would address anything important enough for me to want to read to the end. Then I reached an impressive part: a description of an objective IQ-like measure. Hernández-Orallo offers a test (called the C-test) which:

  • measures a well-defined concept: sequential inductive inference,
  • defines the correct responses using an objective rule (based on Kolmogorov complexity),
  • with essentially no arbitrary cultural bias (the main feature that looks like an arbitrary cultural bias is the choice of alphabet and its order)[1],
  • and gives results in objective units (based on Levin’s Kt).

Yet just when I got my hopes up for a major improvement in real-world IQ testing, he points out that what the C-test measures is too narrow to be called intelligence: there’s a 960 line Perl program that exhibits human-level performance on this kind of test, without resembling a breakthrough in AI.
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I’ve recently noticed some possibly important confusion about machine learning (ML)/deep learning. I’m quite uncertain how much harm the confusion will cause.

On MIRI’s Intelligent Agent Foundations Forum:

If you don’t do cognitive reductions, you will put your confusion in boxes and hide the actual problem. … E.g. if neural networks are used to predict math, then the confusion about how to do logical uncertainty is placed in the black box of “what this neural net learns to do”

On SlateStarCodex:

Imagine a future inmate asking why he was denied parole, and the answer being “nobody knows and it’s impossible to find out even in principle” … (DeepMind employs a Go master to help explain AlphaGo’s decisions back to its own programmers, which is probably a metaphor for something)

A possibly related confusion, from a conversation that I observed recently: philosophers have tried to understand how concepts work for centuries, but have made little progress; therefore deep learning isn’t very close to human-level AGI.

I’m unsure whether any of the claims I’m criticizing reflect actually mistaken beliefs, or whether they’re just communicated carelessly. I’m confident that at least some people at MIRI are wise enough to avoid this confusion [1]. I’ve omitted some ensuing clarifications from my description of the deep learning conversation – maybe if I remembered those sufficiently well, I’d see that I was reacting to a straw man of that discussion. But it seems likely that some people were misled by at least the SlateStarCodex comment.

There’s an important truth that people refer to when they say that neural nets (and machine learning techniques in general) are opaque. But that truth gets seriously obscured when rephrased as “black box” or “impossible to find out even in principle”.
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Book review: The Rationality Quotient: Toward a Test of Rational Thinking, by Keith E. Stanovich, Richard F. West and Maggie E. Toplak.

This book describes an important approach to measuring individual rationality: an RQ test that loosely resembles an IQ test. But it pays inadequate attention to the most important problems with tests of rationality.


My biggest concern about rationality testing is what happens when people anticipate the test and are motivated to maximize their scores (as is the case with IQ tests). Do they:

  • learn to score high by “cheating” (i.e. learn what answers the test wants, without learning to apply that knowledge outside of the test)?
  • learn to score high by becoming more rational?
  • not change their score much, because they’re already motivated to do as well as their aptitudes allow (as is mostly the case with IQ tests)?

Alas, the book treats these issues as an afterthought. Their test knowingly uses questions for which cheating would be straightforward, such as asking whether the test subject believes in science, and whether they prefer to get $85 now rather than $100 in three months. (If they could use real money, that would drastically reduce my concerns about cheating. I’m almost tempted to advocate doing that, but doing so would hinder widespread adoption of the test, even if using real money added enough value to pay for itself.)

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[Caveat: this post involves abstract theorizing whose relevance to practical advice is unclear. ]

What we call willpower mostly derives from conflicts between parts of our minds, often over what discount rate to use.

An additional source of willpower-like conflicts comes from social desirability biases.

I model the mind as having many mental sub-agents, each focused on a fairly narrow goal. Different goals produce different preferences for caring about the distant future versus caring only about the near future.

The sub-agents typically are as smart and sophisticated as a three year old (probably with lots of variation). E.g. my hunger-minimizing sub-agent is willing to accept calorie restriction days with few complaints now that I have a reliable pattern of respecting the hunger-minimizing sub-agent the next day, but complained impatiently when calorie restriction days seemed abnormal.

We have beliefs about how safe we are from near-term dangers, often reflected in changes to the autonomic nervous system (causing relaxation or the fight or flight reflex). Those changes cause quick, crude shifts in something resembling a global discount rate. In addition, each sub-agent has some ability to demand that it’s goals be treated fairly.

We neglect sub-agents whose goals are most long-term when many sub-agents say their goals have been neglected, and/or when the autonomic nervous system says immediate problems deserve attention.

Our willpower is high when we feel safe and are satisfied with our progress at short-term goals.

Social status

The time-discounting effects are sometimes obscured by social signaling.

Writing a will hints at health problems, whereas doing something about global warming can signal wealth. We have sub-agents that steer us to signal health and wealth, but without doing so in a deliberate enough way that people see that we are signaling. That leads us to exaggerate how much of our failure to write a will is due to the time-discounting type of low willpower.

Video games convince parts of our minds that we’re gaining status (in a virtual society) and/or training to win status-related games in real life. That satisfies some sub-agents who care about status. (Video games deceive us about status effects, but that has limited relevance to this post.) Yet as with most play, we suppress awareness of the zero-sum competitions we’re aiming to win. So we get confused about whether we’re being short-sighted here, because we’re pursuing somewhat long-term benefits, probably deceiving ourselves somewhat about them, and pretending not to care about them.

Time asymmetry?

Why do we feel an asymmetry in effects of neglecting distant goals versus neglecting immediate goals?

The fairness to sub-agents metaphor suggests that neglecting the distant future ought to produce emotional reactions comparable to what happens when we neglect the near future.

Neglecting the distant future does produce some discomfort that somewhat resembles willpower problems. If I spend lots of time watching TV, I end up feeling declining life-satisfaction, which tends to eventually cause me to pay more attention to long-term goals.

But the relevant emotions still don’t seem symmetrical.

One reason for asymmetry is that different goals imply different things for what constitutes neglecting a goal: neglecting sleep or food for a day implies something more unfair to the relevant sub-agents than does neglecting one’s career skills.

Another reason is that for both time-preference and social desirability conflicts, we have instincts that aren’t optimized for our current environment.

Our hunter-gatherer ancestors needed to devote most of their time to tasks that paid off within days, and didn’t know how to devote more than a few percent of their time to usefully preparing for events that were several years in the future. Our farmer ancestors needed to devote more time to 3-12 month planning horizons, but not much more than hunter-gatherers did. Today many of us can productively spend large fractions of our time on tasks (such as getting a college degree) that take more than 5 years to pay off. Social desirability biases show (less clear) versions of that same pattern.

That means we need to override our system 1 level heuristics with system 2 level analysis. That requires overriding the instinctive beliefs of some sub-agents about how much attention their goals deserve. Whereas the long-term goals we override to deal with hunger have less firmly established “rights” to fairness.

Also, there may be some fairness rules about how often system 2 can override system 1 agents – doing that too often may cause coalitions within system 1 to treat system 2 as a politician who has grabbed too much power. [Does this explain decision fatigue? I’m unsure.]

Other Models of Willpower

The depletion model

Willpower depletion captures a nontrivial effect of key sub-agents rebelling when their goals have been overlooked for too long.

But I’m confused – the depletion model doesn’t seem like it’s trying to be a complete model of willpower. In particular, it either isn’t trying explain evolutionary sources of willpower problems, or is trying to explain it via the clearly inadequate claim that willpower is a simple function of current blood glucose levels.

It would be fine if the depletion model were just a heuristic that helped us develop more willpower. But if anything it seems more likely to reduce willpower.

Kurzban’s opportunity costs model

Kurzban et al. have a model involving the opportunity costs of using cognitive resources for a given task.

It seems more realistic than most models I’ve seen. It describes some important mental phenomena more clearly than I can, but doesn’t quite seem to be about willpower. In particular, it seems uninformative about differing time horizons. Also, it focuses on cognitive resource constraints, whereas I’d expect some non-cognitive resource constraints to be equally important.

Ainslie’s Breakdown of Will

George Ainslie wrote a lot about willpower, describing it as intertemporal bargaining, with hyperbolic discounting. I read that book 6 years ago, but don’t remember it very clearly, and I don’t recall how much it influenced my current beliefs. I think my model looks a good deal like what I’d get if I had set out to combine the best parts of Ainslie’s ideas and Kurzban’s ideas, but I wrote 90% of this post before remembering that Ainslie’s book was relevant.

Ainslie apparently wrote his book before it became popular to generate simple models of willpower, so he didn’t put much thought into comparing his views to others.

Hyperbolic discounting seems to be a real phenomenon that would be sufficient to cause willpower-like conflicts. But I’m unclear on why it should be a prominent part of a willpower model.


This “model” isn’t designed to say much beyond pointing out that willpower doesn’t reliably get depleted.


A Hot/cool-system model sounds like an attempt to generalize the effects of the autonomic nervous system to explain all of willpower. I haven’t found it to be very informative.


Some say that willpower works like a muscle, in that using it strengthens it.

My model implies that we should expect this result when preparing for the longer-term future causes our future self to be safer and/or to more easily satisfy near-term goals.

I expect this effect to be somewhat observable with using willpower to save money, because having more money makes us feel safer and better able to satisfy our goals.

I expect this effect to be mostly absent after using willpower to loose weight or to write a will, since those produce benefits which are less intuitive and less observable.

Why do drugs affect willpower?

Scott at SlateStarCodex asks why drugs have important effects on willpower.

Many drugs affect the autonomic nervous system, thereby influencing our time preferences. I’d certainly expect that drugs which reduce anxiety will enable us to give higher priority to far future goals.

I expect stimulants make us feel less concern about depleting our available calories, and less concern about our need for sleep, thereby satisfying a few short-term sub-agents. I expect this to cause small increases in willpower.

But this is probably incomplete. I suspect the effect of SSRIs on willpower varies quite widely between people. I suspect that’s due to an anti-anxiety effect which increases willpower, plus an anti-obsession effect which reduces willpower in a way that my model doesn’t explain.

And Scott implies that some drugs have larger effects on willpower than I can explain.

My model implies that placebos can be mildly effective at increasing willpower, by convincing some short-sighted sub-agents that resources are being applied toward their goals. A quick search suggests this prediction has been poorly studied so far, with one low-quality study confirming this.


I’m more puzzled than usual about whether these ideas are valuable. Is this model profound, or too obvious to matter?

I presume part of the answer is that people who care about improving willpower care less about theory, and focus on creating heuristics that are easy to apply.

CFAR does a decent job of helping people develop more willpower, not by explaining a clear theory of what willpower is, but by focusing more on how to resolve conflicts between sub-agents.

And I recommend that most people start with practical advice, such as the advice in The Willpower Instinct, and worry about theory later.

I’ve substantially reduced my anxiety over the past 5-10 years.

Many of the important steps along that path look easy in hindsight, yet the overall goal looked sufficiently hard prospectively that I usually assumed it wasn’t possible. I only ended up making progress by focusing on related goals.

In this post, I’ll mainly focus on problems related to general social anxiety among introverted nerds. It will probably be much less useful to others.

In particular, I expect it doesn’t apply very well to ADHD-related problems, and I have little idea how well it applies to the results of specific PTSD-type trauma.

It should be slightly useful for anxiety over politicians who are making America grate again. But you’re probably fooling yourself if you blame many of your problems on distant strangers.

Trump: Make America Grate Again!

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I started writing morning pages a few months ago. That means writing three pages, on paper, before doing anything else [1].

I’ve only been doing this on weekends and holidays, because on weekdays I feel a need to do some stock market work close to when the market opens.

It typically takes me one hour to write three pages. At first, it felt like I needed 75 minutes but wanted to finish faster. After a few weeks, it felt like I could finish in about 50 minutes when I was in a hurry, but often preferred to take more than an hour.

That suggests I’m doing much less stream-of-consciousness writing than is typical for morning pages. It’s unclear whether that matters.

It feels like devoting an hour per day to morning pages ought to be costly. Yet I never observed it crowding out anything I valued (except maybe once or twice when I woke up before getting an optimal amount of sleep in order to get to a hike on time – that was due to scheduling problems, not due to morning pages reducing the available of time per day).
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