The IQ debates are, to me, tiresome. I’m pretty high IQ, not what I consider genius level (I’ve encountered true geniuses) but just under, in the one-in-ten thousand range. Which is to say, if I’m around 10K people I expect that no one is smarter than me, unless it’s a place that selects for IQ. At MIT I’d be nothing special.
But what I’ve also noticed is that high IQ, and I’ve spent a lot of time around high IQ people and reading them, has very little correlation to being right about the sort of problems which interest me. Virtually all the high IQ economists were wrong about, well, everything, for generations. Larry Summer is extremely high IQ and he’s reliably wrong. If you want to be right about something, find out what Larry Summers thinks, and you at least know one wrong view.
IQ is very good at following rules, even very complicated ones, at seeing correlations and at pattern matching. Without judgment all IQ does is get you to where everyone who shares your priors, as the youngs say (I call them axioms or assumptions), faster.
I also believe that IQ can change over time. The more you do of something, the better you get at whatever that is. Being good at economics makes you better at economics and the types of reasoning and math it uses. (It does not make you better at understanding economies, that’s something entirely different.)
And I think that IQ is only somewhat heritable.
Right now we’re in an period where the consensus among smart non-specialist is that IQ is highly heritable and most of this comes from the result of twin studies.
The conclusion is that these studies are extremely flawed and can’t be used to make the claims made. The twins were often placed separately not immediately after birth, in fact in some cases as late as eight years old. The effects of mother’s on babies in the womb is huge (smoking, drinking, lead exposure) and that’s environment, many of them were placed with extended family and almost all were placed with middle class families similar to the ones they came from.
This debate matters. High heritability means that certain families are just superior. Bessis has a good summary of this. (The current strong case is 80% heritability.) I’m going to quote him here:
Let’s say, for example, that you are a genetically average person. How much does that affect your prospects?
- Surprisingly, at 30%, it’s as if your genes didn’t matter at all. With an average potential, you still have a decent chance of landing at the top or bottom of the IQ distribution. Actually, in this specific random sample, one of three smartest people around (the top 0.3%) happens to have an almost exactly average genetic make-up, and the fourth dumbest person has a slightly above-average potential.
- At 50%, being genetically average starts to limit your optionality, but the spread remains massive. Had you been marginally luckier—say, in the top third for genetic potential—you’d still have a shot at becoming one of the smartest people around.
- At 80%, though, your optionality has mostly vanished. It’s still possible to move a notch upward or downward, but the game is mostly over. In this world, geniuses are born, not made.
This discussion is generally omitted by hereditarians, which is unfortunate, because it is the only way to clarify the stakes. There is a fundamental asymmetry in the debate. Heritability matters a lot when it is extremely high, because it then supports genetic determinism, but for the rest of the range the exact figure has little practical significance.1
Now while Bessis doesn’t go into it, what I find even more disturbing are the racial/ethnic version of genetic IQ determinism. I think they’re largely bunk (that’s another post) but many very smart people believe them. Koreans and Chinese and Ashkenazi Jews are smarter than whites who are smarter than blacks and so on, and this is taken to explain differences in how well various countries do, not their history or their environment. Blacks are, in this view, innately stupid. It’s not that they were colonized and brutalized and that the environments they grow up in are harmful to IQ development, nope, it’s innate.
If heritability is 80%, well, they just “deserve” their fates, and there’s really nothing that can be done about it. (If IQ determines national success, which is also BS if you ask me. If it was that simple, China would never have had its century of humiliation and whites shouldn’t have ruled the world for hundreds of years when Chinese and Koreans and Ashkenazi Jews are so superior to us.)
It’s not, in this view, that Talmudic study and cultures that place an obsessive value on learning like Korea and China do, develop higher higher IQs, it’s that they start smarter.
Now, as with Bessis, I think there IS a genetic component to IQ. It’s not like it doesn’t matter at all. I just think other things matter too, and that IQ matters less than people think it does.
We may revisit this issue, though I’m unsure. For a lot of my writing career I spent a great deal of effort debunking bullshit. The problem is that it never works, most people aren’t convinced, it takes longer to debunk than produce, and there’s always more of it because the pernicious types of bullshit are highly funded. It’s hard to compete with entire think tanks spewing out garbage, and that’s the job of 90% of think tanks: what they believe is pre-determined, donors want “intellectual” arguments to back up what they already believe or what they want others to believe because it is beneficial to them.
If excellence, however determined, is 80% hereditary, then aristocracy, however defined, is justifiable. The best people come from certain genetic lineages and deserve their place in the world. Whites deserve to be above blacks, Chines and Koreans above whites, and Ashkenazi Jews are the super race. (As an aside, though not genetic, trans women blow Ashkenazi out of the water in terms of average IQ, which I find hilarious, since it means that the people who love IQ and think it’s determinitive, should love trans women.)
It also means that there’s one less reason to improve circumstances of the majority of people. The few sports will rise to their level of genetic fitness and everyone else deserves to be where they are and doesn’t need support to improve their excellence, since that’s determined by genetics not environment.
This stuff is fought over because it matters, just like the divine right of Kings mattered. It’s about justification of how society runs, or an argument to change how society treats different people. Material circumstances matter, but so do ideas. We are slaves to what we believe the world is like and what we believe people are like. We often act on those beliefs. As the sociological maxim says “things believed true have real consequences even if not true.”
Twin studies don’t show 80% hereditability because those studies were extremely flawed. That matters.
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Eric Anderson
Now do the difference between average intelligence old parents vs average intelligence young parents and you’ll really see how much more nurture influences intelligence than nature.
spud
smart people do dumb things all of the time. its why meritocracy always fails.
vmsmith
“I just think . . . that IQ matters less than people think it does.”
Well, the first question I would have is: Matters in what?
That said, I tend to agree that IQ matters less in worldly success—and by that I mean, something akin to career or vocational success—than most people think it does. I think luck plays a much, much larger role in worldly success than IQ. You can find scads written about that, but just look at Warren Buffett as an example.
Buffett undoubtedly would have been successful to some degree anyway, but his outsize success had at least three elements of luck that few people think about:
1. He was born at just the right time to take advantage of the post-WWII boom.
2. He was able to take classes at Columbia with Benjamin Graham.
3. He met Charlie Munger, which was probably the luckiest thing in his life.
By most instruments of measure, I, too, am well above average in IQ. I find the entire discussion somewhat tiresome, though. So many other things matter more in almost whatever domain you choose (math, logic, and any domains of pure thought might be exceptions). Exhibit A: Larry Summers.
someofparts
I spent the last twenty years of my work life being careful to only use small words when talking to the people I worked for, because if I spoke normally I used words they didn’t understand and they would fire me for it. The people with substantial material resources that I know are all like little spin-offs of Larry Summers, unpleasant little cocktails of self-importance and ignorance.
Purple Library Guy
I’ve never taken an IQ test. I never felt very confident about the idea that such a test could measure anything all that important . . . I mean, if you look at the debates in the education field about testing in general it’s pretty clear that a test purporting to measure “intelligence” (without really defining it) is going to be problematic. Then I found out that the originator of the tests that became “IQ tests” did not even intend them as a measure of some static capacity, but as a baseline to figure out what kind of teaching people needed. Then I read Stephen Jay Gould’s “The Mismeasure of Man” and really concluded the whole enterprise was more danger than use.
However, IF IQ tests did measure intelligence, and IF the intelligence they measured was strongly heritable at that 80% or so level, which I doubt, it would NOT establish a GENUINE justification for aristocracy. On what ethical basis can we say that intelligent people are more deserving? Lots of smart people are parasitic on society–look at the whole financial, advertising and PR industries. Just because intelligence may give people advantages does not mean those advantages are deserved. Strong people also have advantages; part of what society is about is precisely to blunt that kind of advantage. Studies show height gives people advantages; should we have an aristocracy of tall people? The only quality I can imagine an ethical defence for as a basis for aristocracy would be an aristocracy of NICE people (which unfortunately lets me out).
different clue
What if IQ is just a measure of cleverishly verbalose prolixitude? I would imagine that if you were very clever and you understood how IQ tests work , that you could spoof the test and get yourself assessed as high IQ. ( I’ve never actually taken such a test so I don’t know).
And of course ” intelligence” would also mean “intelligence for what” and ” in what context”. If an Ashkenazi Talmudic scholar were given an IQ test based on all the intricate knowledge involved in successfully herding and protecting cattle on the Serengeti Plain, he would score a near-zero IQ. If a Maasai herdsman were given an IQ test based on a deep and detailed knowledge of the intricacies of Talmudic text and Talmudic law, he would score a near-zero IQ.
So ” IQ” is really just a measure of profficiency at taking the IQ test.
Or am I wrong? ( as Billo Reilly likes to ask).
Jan Wiklund
Is there any good definition of what IQ is? As far as I know, it was invented by Alfred Binet to decide which 7 years old was fit for schooling and which were not. And to this day, it favours qualities that fit schooling, but not necessarily other activities.
More than 50 years ago I was tested by one of the most respected Swedish institution at the time and got the grade that I belonged to the top 4 percent of those who had passed secondary school (or college, as the Americans say). But I have met hosts of people I judged were quite at my level, or more. Just that I may have excelled in some pursuits (seeing structures, for example) and they in others.
I certainly believe the whole IQ discussion as a hype. Excellence has qualities. Where there are tops there are valleys, as Peter Drucker said. The same people rarely excel over the wole horizon. Or, to return to the Summers case: one of the verses by Danish mathematician and poet Piet Hein runs something like “The worst idiot I have ever known, was also very intelligent” (it rhymes in Danish).
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I think luck plays a much, much larger role in worldly success than IQ.
No doubt luck plays some part but not a large part, imo. Wiles plays a much larger part and wiles is not dependent on IQ. Trump is a dumbass. He does not have a high IQ. But he sure as hell has wiles and who could argue, by conventional standards at least, he is a yuuuge success? None of us, for example, could boast we could destroy the world at this very moment if we so wished but DJT with the unremarkable IQ, maybe even low IQ, but remarkable wiles could and maybe he will and put all of us out of our coolective nightmarish misery.
GrimJim
IQ tests only measure one’s ability to take IQ tests, which are essentially designed to measure adaptation to and knowledge of things that are important in modern “Western” “civilization.”
They have nothing to do with real intelligence or knowledge.
A man with an “IQ” of 175 and no experience in survival dropped into the Amazon is about as smart as a rock.
Measuring the intelligence of anyone who is not white, Christian, middle class or better, and male who was raised in the US or Europe by using “IQ” is a racist and sexist exercise.
Dan Lynch
The Rawlsian view, if I understand it correctly, is that we should strive for a society where we would be treated decently if, whether due to genetics or environment, we had low IQ, or medium IQ, or high IQ.
Hence I don’t think geniuses or PhD’s should be paid more than janitors. If someone is a genius or a PhD, it’s because they won the genetic & environmental lottery, not because they “earned it.” They may have studied hard, but janitorial work is hard, too.
That doesn’t mean I believe janitors should be running the country, just that they should be treated decently, and not looked down upon.
marku
That Bessis article is quite brilliant. He actually tracked down the studies read them, and determined that they were all flawed in strong ways, and one was outright fraud (he concealed a data set that at minimum, would undermine his conclusion, and perhaps destroy it.)
StewartM
I’ve read Stephen Jay Gould’s critique of notions of a unitary, scalar, heritable, thing called “intelligence” and I agree with him that it’s simply unproven, and indeed unlikely. For one thing, my interactions with “smart people” generally indicate that they are superior ability is one or several mental attributes, but not in all. There is no indication that Shakespeare would have been a great painter, or Mozart a skilled pool player (spatial recognition) or that Newton would have been a superb music composer. In fact, “idiot savants” (who are genius-level in some mental skills but subpar in most) seem to strongly indicate that there is no unitary one thing called “intelligence”.
But even to the degree that “intelligence” is heritable, the best metaphor is to think of the brain as akin to a muscle. Micheal Jordan had all the physical traits to become a world-class basketball player, but without the opportunity and his determination to be one he would not have become one. Bobby Fischer’s skill as a chess player also may have required innate abilities, but again they were equally the product of his almost manic determination to excel. I have a Sciam article about this, and it concluded (and I agree) that it takes about 10,000 hours of focused learning to achieve excellence in any skill. 10,000 hours means it takes at least ten years, and usually more, to achieve excellence as in most careers we end up doing already-mastered skills most of the time.
Ian, you have often commented on the astonishing lack of competence in US leadership; and I agree. The very reason why we lack this, I think, is that we’ve allowed our leadership to skip and take shortcuts to the hard work of becoming excellent on the way to the top. On Linkedin I got into a debate with a woman who calls herself an “Entrepreneur, Inventor, Tesla Manager, Small Business Developer, Credentialing Manager, Healthcare Manager, and Administrative Accounting Assistant” on career shifts, and she claimed that jumping careers was a good thing because “after five years you will know everything there is to know about any one job”. I tried to explain to her why this isn’t so; I spent almost 30 years in one technique area/skill set and I still was learning new things at the end of my career; other things I knew theoretically but theoretical knowledge isn’t the same as having practical experience with it. I also told her about the 10,000 hour rule.
Her reply was “Well, some people are slow learners”. My conclusion? She not only hasn’t achieved excellence in anything, she doesn’t even recognize it when she sees it.
This is what our current leadership looks like. People who did not start at the bottom and work their way up, did not have to show excellence at any particular skill, but just went through the motions in all their “starter jobs” to the top, where—because they already think they know everything and are “geniuses”–take a wrecking ball to institutional knowledge, knowledge that they don’t even begin to understand. That’s happened at companies starting with Jack Welsh, and now it’s happened to the US government starting with DOGE (though RFK Jr. is probably the best poster child).
mago
There are a few brands of human intelligence: critical, analytical, emotional and intuitive, for example. One can be a mathematical genius and a social retard—I’ve known a few, both as friends and students.
I find the IQ rating misleading. Not having taken the test I don’t know where I fall along the spectrum, although when I was younger I identified as an intellectual, which was no more than youthful vanity.
I have acquired a vocabulary along the way, and like someofparts I tailor my communication according to audience most of the time, not wishing to be accused of putting on airs.
Anyway, i value intuition and an ability to connect dots more than so called book learning, although i respect that as well. It’s not so common anymore, just like common sense.
Also, one should not underestimate the intelligence of animals. I have opportunity to observe both wild and domestic animals and dumb is not a word I would use to describe them, although that’s precisely how stupid humans perceive them.
It’s hard to make sense of most anything anymore in these dumb downed days, er, daze. But gotta keep on trying. . .
spud
https://www.youtube.com/watch?v=Ehn1QoQPozM
Why Traitors and Billionaires Always Look Like Geniuses – Barry’s Economics
Soredemos
Any notion of Jewish superiority is disproven by Israel itself. Talk about a thuggish, stupid, and culturally dead society.
To the extent there’s anything too Jews being elites, it’s due to their outsider status, similar to Chinese in parts of broader Asia. But also a lot of it is simple nepotism. Jews are, for example, comically overprepresented in places like Hollywood. And also many of these producers, writers, directors, etc, are fucking hacks.
GlassHammer
In my time I haven’t seen as tight a connection between high IQ and high mastery/proficiency as I would have expected. I am sure the reasons for this generally overlap with what Ian has posted just now and his previous posts.
But I will add another, high IQ doesn’t mean the individual has a strong compulsion to tinker or simply try something a bit foolish just to see what happens.
In fact there is this really funny phenomenon where the smartest person is so against looking foolish due to their tinkering going awry, that they have to get inspiration from watching an actual fool give it a go. If your on a major project that is stalled due to risky decisions needing to be made, watch your engineers start following around the frustrated worker who just uttered the words “Screw it, I will do it myself!” Whatever happens… those engineers will end up having what they need to show the boss the “correct decisions”. That poor worker…. well assuming they go unscathed will be looking at a reprimand at the very least but will get absolutely no praise for doing what those engineers were a bit too afraid to try.
edwin
I’m going to avoid the words IQ and use intelligence instead.
This article immediately made me think of the Oneida flatware and the Oneida commune – 1848 to 1881. They weren’t interested in increasing intelligence, but rather breeding for spirituality and morality. It may be worth asking, just how heritable is spiritually and morality? There are lots of things that are controversial about the Oneida commune. Some of which readers of this blog may be sympathetic with, some probably not. Does intelligence exist at least in part in the eyes of the beholder? Spirituality clearly does, as does morality.
There is intelligence as an individual and as a species. A cat has intelligence that almost always exists within a range with the upper bound perhaps being more important. It does not look like we are going to breed a cat Einstein anytime soon let alone have one randomly show up. I think that the same can be said for people. No matter how inheritable intelligence is, there will be some rather strong limits to that intelligence.
I think that what people want is for someone to wave their magic wand – or in today’s world – perform gm or implant a chip and make them into superman.
“I think there IS a genetic component to IQ. It’s not like it doesn’t matter at all. I just think other things matter too, and that IQ matters less than people think it does.” I can get behind this.
bruce wilder
The skepticism of this post and most of the comments resonate with my thinking and experience.
I am not sure I know what “intelligence” is. If it is a quality measured by IQ tests, what exactly is measured by IQ tests? I have never seen a clear, verified account.
And, then there’s this business of rendering degree of heritability as a percentage. What is the denominator and what is the numerator of this putative fraction? Oh! You are doing analysis of variance? That clears it right up for me . . . NOT!
You are doing an analysis of variance for the inheritance of this observed characteristic, intelligence, as measured by one, specific, validated test or a variety of tests? Measurement error an issue? Your linear model for the determination of intelligence in an individual or a group?
For me, the obstacles to clear thinking pile higher and higher. Do we model “intelligence” as analogous to, say, height? Height can be accounted for by a single, scaled value and without knowing much about the biological specifics, I imagine multiple genetic and developmental factors affect the outcome. Do I think those factors combine linearly to produce height? Hmmm.
OK, do I model “intelligence” as analogous to handsome? Not as preposterous as it sounds, but it does suggest the difficulty. Lewis Terman’s Stanford studies of the gifted noted the association between being attractive and being smart. Admittedly, it may be what Terman wanted to believe.
I don’t know what “80%” means in this context. If I maximize the quality of environment — protection from disease, good nutrition, stimulation of intellect — should I expect “intelligence” to be 100% genetic? There is an argument that that would be the case for “height” isn’t there? And a similar but subtly different argument for “handsome”. Make variation in the environment more extreme — starve some kids in your sample — and environmental factors gain weight.
Anyway, that is my puzzlement with this topic proceeds.
Dagnarus
“If heritability is 80%, well, they just “deserve” their fates, and there’s really nothing that can be done about it.”
I don’t really see this personally. If the voice of God came down and revealed to every leftist that IQ was 80% heritable, I don’t think we would then suddenly accept, oh well then, we should just accept Shit wages, then quietly go into the corner and die when replaced by robots.
If the libertarians were informed by god that 30% Heritability was the case, I doubt they would suddenly decide that resources should then be distributed based upon a person’s IQ based upon a supposed optimal upbringing.
If God chose to speak to the EthnoNationalists on the subject, I doubt it would change there mind about getting A blond, blued eyed Aryan to impregnate there wife on the weekend. That being more a fetish than a selective breeding thing I suspect.
somecomputerguy
The conceptual framework called “Intelligence” originated before even the beginning of scientific understanding of how the brain works.
We don’t know why the brain needs sleep, but we can actually measure how good a brain you have?
This is a conceptual framework so tainted that using it is actual obstacle to understanding.
KT Chong
Chinese belief framework on IQ, race, and development:
• IQ is largely heritable.
Intelligence is not created from nothing; education refines it, but genetics and early development matter a lot.
• Race / population matters at the aggregate level.
Different populations show different average IQs in the real world. This is obvious to most Chinese and not controversial culturally.
• Racial / population IQ is NOT static or fixed forever.
This is where Westerners misunderstand Chinese thinking: Differences are real, but they are changeable.
• IQ is capped within a generation.
For any given individual: Early nutrition, early childhood stimulation, parental IQ, stress, disease, religiosity, schooling, etc., impose a real biological limit. Later interventions help, but only up to a point.
• That cap is effectively a “hard ceiling” for the individual.
If a kid from a deprived environment started at IQ ~78, (i.e., he was born in a country with low mean IQ,) but then he was removed from that environment put into the a developed country, a good school, a privileged environment, and later he gained +14 points, (i.e., the typical maximum possible improvement someone from a disadvanged background could gain from better environment and schooling,) his IQ ended at around ~92
That is not random.
That is not infinite malleability.
That is a real developmental ceiling for him
However, his offspring will start at a higher IQ and have a higher ceiling — that is an inheritable part of intelligence.
• Outliers exist, but they don’t define the population.
Geniuses can appear anywhere, but they are statistical tails, not evidence against population patterns.
• The cap/ceiling moves across generations, not within one lifetime.
This is the core Chinese intuition:
Gen 1: modest gains
Gen 2: more gains compounded atop of Gen 1 gins
Gen 3: more gains, mass production of high-level talents
A nation, a population, a race, can build intelligence just as wealth in three generations.
• Good policy works biologically, but gradually.
Nutrition, education, stability, and early stimulation don’t just raise test scores — they raise the next generation’s baseline.
This can happen fast — 1 to 3 generations.
Not centuries.
We’ve already seen this in: Japan, South Korea, China, ASEAN countries
• Europe was ahead earlier because it developed earlier.
Europeans reached close to the human IQ ceiling earlier due to: Better nutrition (protein-rich environment, developed a tolerance for lactose/protein = huge boost in brain development and power), earlier industrialization, stable institutions
Not because they are uniquely special biologically.
• Other regions are now catching up.
As environments improve, populations move upward toward the same ceiling.
• There is an absolute hard ceiling for humanity as a whole.
Across all races: Human cognitive potential maxes out somewhere around ~120 IQ (rough estimate).
No race exceeds this.
Some populations reached it earlier.
Others haven’t reached it yet
• So the picture is layered, not simplistic:
Individual IQ: capped by early development
Population IQ: capped within a generation
Population IQ across generations: improvable
Humanity as a whole: absolutely capped
• Race is not destiny, but it is not irrelevant either.
Race functions as a proxy for long-run developmental history.
Denying that is denial of reality; claiming it is permanent is also wrong.
different clue
@somecomputerguy,
I believe some research into living mouse-brains while those mice are asleep has discovered that during sleep the glial cells inside their brains shrink in size, thereby creating space for cerebrospinal fluid to enter those spaces. Metabolic waste from brain neurons seeps and filters from the sleeping mouse-brain neurons into the cerebrospinal fluid in the spaces between the neurons. As part of the waking-up process, the mouse-brain glial cells swell back up and force the metabolic-waste-laden cerebro-spinal fluid back into the bigger spaces for it around the spinal cord for further movement into the lymphatic system for even more further movement to the bloodstream and thereby to the kidneys for disposal.
If the sleeping human brain functions like the mouse brain, then the same thing would be happening in our sleeping brains. That would be one function of sleep among all the others.
KT Chong
Ian Welsh: “But what I’ve also noticed is that high IQ, and I’ve spent a lot of time around high IQ people and reading them… IQ is very good at following rules, even very complicated ones, at seeing correlations and at pattern matching. Without judgment all IQ does is get you to where everyone who shares your priors, as the youngs say… faster.”
Not really.
IQ differences are real. And if you only interact with smart people, you don’t actually understand how big those differences are. They become obvious only when you teach or manage across the full spectrum.
Teach the same thing to different people:
• High-IQ people need minimal instruction.
You explain once, maybe show once, and they immediately get it.
• Low-IQ people require repeated instruction for the same lesson.
You explain again and again. You demonstrate step by step. They forget, misunderstand, or misapply it. Progress is slow and fragile.
This difference is qualitative, not just quantitative. The limitation is not environmental or psychological — it’s cognitive.
Low-IQ people are often genuinely trying. They just cannot absorb, abstract, retain, or transfer knowledge as quickly or as reliably as high-IQ people.
This is why mass education so often fails either high-IQ or low-IQ students, or both. You can’t scale one-size-fits-all learning to everyone. Over time, systems adjust the bar to teach to the middle — or to the lowest common denominator.
Anyone who has taught, managed, trained, or mentored across real ability ranges eventually reaches this conclusion.
KT Chong
Another real difference between high-IQ and low-IQ individuals — handling complexity and multitasking
From both personal experience and research, there are systematic cognitive differences in how high-IQ and low-IQ people deal with complexity, multitasking, and cognitive load.
1) Working memory and complexity
Intelligence and working memory capacity (WMC) are strongly linked. Working memory is a core component of what IQ tests measure and what intelligence actually relies on. High WMC means being able to hold more information in mind at once and coordinate it — a key requirement for complex, multi-step tasks.
When tasks become complex, people with higher working memory (and thus higher IQ) can maintain more variables, rules, and steps without losing track. People with lower working memory start to struggle as soon as the information load increases.
That’s why:
• Low-complexity tasks don’t show large differences between high-IQ and low-IQ people.
• High-complexity tasks separate performance sharply.
The smarter person does not get “confused” or lose their place halfway through a multi-part task.
The less intelligent person becomes confused, overwhelmed, and makes more mistakes.
2) Multitasking performance
General intelligence and working memory both correlate with multitasking ability. But working memory explains more of the difference — because what looks like “multitasking” is usually not doing two things independently, but holding, sequencing, and switching between task sets.
This capacity is closely related to fluid intelligence.
In practice:
• People with higher working memory and fluid intelligence manage task switching more efficiently.
• People with lower working memory suffer larger performance drops and slow down significantly as tasks accumulate.
So what appears to be “multitasking without overwhelm” is really efficient allocation of cognitive resources under load.
3) Neural efficiency and complexity handling
High-intelligence individuals tend to use their brains more efficiently. They accomplish the same tasks with less unnecessary neural effort.
This is known as neural efficiency.
That’s why a high-IQ person can remain calm, accurate, and organized under complexity. Their brain doesn’t “burn out” or strained as easily doing the same work, allowing them to keep more logic in play without fatigue or under pressure.
4) Attention control and cognitive resources
Tasks that require managing conflicting information, filtering out distractions, or rapidly shifting focus reveal differences in how attention and cognitive control are deployed.
• High-intelligence people are often better at allocating attention and resisting interference, which makes them more stable under complexity.
• Low-intelligence individuals show bigger performance drops when the task presents competing demands or distractors.
This is why:
• low-complexity tasks look easy for everyone,
• high-complexity tasks reveal large differences.
One more personal observation:
I also have one more personal observation about smart people — and why they are often the very people who do not believe IQ differences exist or matter…
Ian Welsh
You’re talking about teaching people KT. I’m talking about using what is learned. I’m 3 standard deviations up. I’ve dealt with people 4 and 5 standard deviations and beaten them repeatedly because I have judgment and they don’t. If IQ was all that mattered that wouldn’t have happened, but it did. One particular individual was a polymath and polyglot – Phd level math, physics, biology and history, plus significant artistic accomplishments. I was still right about big calls they missed, but they were unquestionably higher IQ than I am. They had creativity and higher IQ, but I have better judgment.
And I’ve taught people from about 90 IQ on up.
How intelligence, judgment and creativity interact is something I’ve spent a lot of time on. IQ by itself is nice, but without judgment and/or creativity it just makes you Larry Summers.
We’re not talking about the 100 IQ normals, or the 120 “brights”, we’re talking about people who are in the game, which requires 2 standard deviations minimum. At 3 standard you’re a “poor man’s genius”, you can learn anything, but not everything. At 4, if motivated, you can do the polyglot/polymath thing.
Once you’re in the game, other things matter more than IQ.
Enough work/study of the right kind can shift someone a standard deviation up, as well.
KT Chong
Another observation: why many smart people think IQ “doesn’t matter”
Many people who insist that IQ doesn’t matter are, ironically, highly intelligent themselves.
Why?
They work with other intelligent people.
They socialize with intelligent people.
They went to selective schools, elite workplaces, filtered environments.
They live inside an IQ bubble.
Because of that, they’ve never had to seriously deal with genuinely low-IQ people. They’ve never had to:
• explain the same simple thing ten times,
• watch someone repeatedly lose track of a basic multi-step task,
• or see how quickly confusion and errors pile up under even modest complexity.
So to those smart people, IQ differences are abstract.
Or theoretical.
Or moralized away.
When everyone around you can learn after one explanation, follow rules, handle abstractions, and self-correct, it’s easy to believe:
“Everyone is basically the same”
“Differences are just effort or motivation”
“Environment explains everything”
But that belief collapses the moment you leave elite environments (like academia) and interact across the full cognitive distribution.
People who deny IQ differences usually lack exposure, not insight. They mistake selection effects for reality.
Ironically, the people most confident that “IQ doesn’t matter” are often the least qualified to judge — because they’ve never had to manage, teach, or train people who sit far below them cognitively.
Once you do, the differences stop being ideological. They become practical, unavoidable, and impossible to unsee.
Final Words:
I was in academia, surrounded by smart people.
Then I left and joined a startup, worked insane hours, and was surrounded by people who were even smarter.
Eventually, I burned out.
After that, I decided to slow down and just relax for a while. I went into social work.
That’s when I started to meet stupid people.
I didn’t even know that level of stupidity existed. It was an eye-opening experience.
For the first time, I was interacting daily with people who:
• couldn’t follow basic instructions,
• couldn’t hold simple sequences in their head,
• couldn’t connect cause and effect,
• and would repeatedly make the same mistakes no matter how many times things were explained.
That experience is why I know low-IQ people exist — and that they are not just “a little slower,” but qualitatively and drastically different from high-IQ people.
It’s offensive to say out loud.
But it’s my experience.
Ian Welsh
I’ve worked construction, trucking, moving, security and fast food. I’m familiar with stupid people.
In social work you don’t just meet stupid people, you meet a lot of people who are damaged. The average trucker has 90 IQ. They’re not bright. But they can do their jobs and have conversations.
KT Chong
Just to be clear: this does not mean I think society should discriminate against low-IQ people.
We have to come up with humane solutions so they’re not abandoned or left behind. No one asks to be born with lesser intelligence. That’s not their fault. In fact, they should be getting more help, not less.
But pretending they could be just as smart as everyone else? That’s actually harmful.
You put them in a competitive environment where the rules, the abstractions, the pace — everything is designed for someone else — and they’re gonna struggle just to keep their heads above water. They fail, over and over. They can’t keep up. Not because they’re lazy or unmotivated, but because the environment is stacked against them.
That’s not equality. That’s ideology disguised as virtue.
The reality is simple: people are different. Abilities are different. Denying IQ differences doesn’t help anyone. It just throws people into situations where they are set up to fail.
That’s my problem with liberals and progressives — they want to bend reality to fit their ideological rigidity.
Ian Welsh
I didn’t deny IQ or intelligence exists. I said it doesn’t matter as much as people think it does, which doesn’t mean it doesn’t matter at all. The article was about how heritable it is, and what the consequences are if it’s more or less hereditible.
Being smart matters, but it’s not the only thing that matters and intelligence without other abilities or virtues often runs you into a propeller at full speed.