= 27d567bc2d48d9f40e9ccc20ea370b15)
gwern comments on Why Are Individual IQ Differences OK? - Less Wrong
You are viewing a comment permalink. View the original post to see all comments and the full post content.
= 783df68a0f980790206b9ea87794c5b6)
Loading…= b715d02e85f7b3b4ae65ca3d3e450868)
Subscribe to RSS Feed
Powered by Reddit
= f037147d6e6c911a85753b9abdedda8d)
You are viewing a comment permalink. View the original post to see all comments and the full post content.
Comments (526)
Why would you think this? Intelligence is metabolically expensive, and pays off only in the long run (consider how much of a life you can 'waste' getting an education). Putting people into a resource-pressured poor quality environment would seem to select for more immediately useful traits like aggression or growing up very quickly (and hence, investing in poorer quality body parts or less of them, like being shorter).
If there were a lot of resources on average but the environment fluctuated a lot, then there might be evolutionary pressure for intelligence: but this does not describe Africa too well and better describes very northern countries like Scandinavia where you can freeze to death but agriculture or fishing etc still yield lots of food. The book does discuss this theory and run some regressions in its favor. (I've always been a little dubious: it seems to me that it largely depends on European countries for most of its value...)
Gifted babies do things sooner - that's how early it shows up. Gifted children can learn to walk sooner, talk sooner, climb sooner, have rational thoughts sooner, etc. I'm not talking about marginally sooner. I'm talking about huge gaps like 1/3 sooner or 3 times sooner, and sometimes even 12 times sooner (William Sidis).
Gifted children tend to be bigger, not smaller - they develop faster. All these things would certainly give them an edge over the other children. They do grow up faster - otherwise what else describes child prodigies? They've reached an adult level of skill as a child. That does happen, you know.
Gifted people tend to be emotionally intense - and of course they may express that in any number of directions (sadness, happiness, anger) which lends itself to the idea that some portion of the gifted population may be easier to provoke to the point of aggression.
And there are different kinds of gifts, different sources of giftedness. Some gifted people only need three hours of sleep, for instance. I've met several bright people that require only three hours a night. That's five extra hours every day. Imagine that all your days are 1/3 longer, and how much of an advantage it would be.
What are these "resources" you keep mentioning? It's not like gifted children eat two elephants a week. They eat normal food.
Do you happen to remember the area of the book dealing with this theory?
All of your points may be true, but are not especially relevant. Philippe Rushton makes much hay in his lifecycle theory of how black kids grow up faster than white kids and much faster than East Asian kids, but that doesn't mean they're destined for genius any more than chimp infants growing up much faster than human infants means anything.
Fats, protein, calories, time-investment, sleep. Feel free to look through http://www.gwern.net/Drug%20heuristics for those (the sleep one IIRC is from Ericsson).
How do you know how much they eat? Have you weighed out their every meal and snack? Just a few hundred calories made the difference between life and death in Nazi concentration camps; how much more so in famines or droughts? Your intuitions from a fat Western First World environment are not very useful in this discussion.
I have, actually, with modafinil. It's not as impressive as one might think; if you weren't being productive with your original waking hours, getting some more is not necessarily going to revolutionize your life. Further, we know that sleep deficits are one of those things that are easy to fool yourself about: the chronically sleep-derived are deluded about whether they are paying any mental price for the sleep deprivation.
There are different speeds at which people grow up, it's not boolean. There are different levels of giftedness. Some are so gifted as to be called geniuses, some are more along the lines of talented, and there are plenty of people in between.
Food: Now that you've said "a few hundred calories makes a difference", I see that this could be a potential setback for them. That was a good point. I don't know whether they eat a bit more or less, though I know that they can experience reactive hypoglycemia if they don't space and balance their meals properly to avoid blood sugar crashes.
Sleep: Gifted children are more likely to need either more or less sleep than average. So far, I've met a bunch of gifted people that need less sleep, and none that need more. If sleep were a survival factor, then the gifted people who need less of it would theoretically just be more populous than the ones who need more. Obviously, the longer sleepers theoretically would not prevent shorter sleepers from surviving better.
It's not 100% clear to me whether brilliant people who sleep 3 hours a night experience sleep deprivation symptoms. However, when you're looking at something as extreme as a 5 hour difference, you'd think the person would unravel very quickly, if they needed those 5 hours. If they're paying a price for it, it's certainly not nearly as bad as the price an ordinary person would pay. A normal person would probably devolve into schizophrenia after a couple weeks of that. But these guys seemed bright and rational.
Einstein and Feynman didn't start to talk until they were 3.
Huh. I didn't know that. My parents thought I was deaf until one day I started talking - in full and coherent sentences.
How common is that?
This old Language Log post discusses some fictional, real and apocryphal cases.
I couldn't give a figure for it but it is a common enough occurrence that my Asperger's Syndrome textbook notes it as a possible outcome.
I had originally read that on the WIkipedia article about Feynman, which links to http://en.wikipedia.org/wiki/Language_delay, which cites http://pinker.wjh.harvard.edu/articles/media/1999_06_24_newyorktimes.html (which I haven't read yet, but I'm going to).
One example: the population is Ashkenazi jews, and the environment is the racist world we live in. It's not clear how much is cultural and how much is genetic, though.
What? If you have in mind things like the Holocaust, remember that the causation goes the other way around. Success breeds resentment, rather than resentment breeding success. Jews are a market-dominant minority, and across the world market-dominant minorities are subject to violence and resentment.
Jewish intelligence is likely due to their particular economic and social position in the middle ages, where they had long-range trust networks that facilitated moneylending and trade, as well as a religious prohibition from marrying with the locals that meant they would specialize more towards their ecological niche. (And it seems likely that they picked that niche because it was a particularly pleasant one, not that they were forced into it by oppression.)
Thanks, it's good to know about market-dominant minorities.
I'm not sure what to do with this information...it seems to accurately describe the situation but is also very disturbing, for two reasons: First, it sounds like blaming the Jews, in that if they were a model (politically-weak) minority instead of a market-dominant minority they wouldn't have been scapegoated for Germany's economic problems, which is terrible (but I'm pretty sure you just are trying to describe the real world, with no value judgments whatsoever meant). Second, I am apparently one of the oppressors of today. Most Americans don't think much about the poor people who make the stuff they buy, or who get exploded by the weapons their military develops.
"Is" doesn't lead to "should", and there's no legal obligation to seek out opportunities to save lives, and I don't have enough power now to make a meaningful difference, but it's really hard to say "I don't care what other people think; I'm going to do what I want!", when every normal American day I burn enough money to support a few impoverished families. If I gave up some luxuries, I could save peoples' lives, but if I give in to that it means the end of my dreams, and would not necessarily do the most good. Most people choose not to think about these things.
Is it time to jump off the slippery slope? I falsely equate being selfish with being evil, because it feels like the cost of embracing selfishness is, to quote Steven Pressfield, to "wind up alone, in the cold void of starry space, with nothing and no one to hold on to." But, being unselfish ends with my death with nothing meaningful changed, and refusing to choose, while easy, is a non-option. I need to not die, and to know the meaning of life, and I want to help others to the extent possible. Owning my place in the real world is painful but seeking oblivion through distracted and unhealthy living, because of my unwillingness to own my place as a subordinate fiend, is worse.
The Ashkenazi Jews are still a small population, though. And intelligence may be an reproductive advantage in their niche, but that's only one niche. If you don't like the example of the Holocaust, consider the Khmer Rouge going after anyone who seemed intelligent.
The Khmer Rouge were dramatic, but I'd bet money that simpler forces have played a greater role in the evolution of intelligence since the Neolithic. As you say upthread, intelligence is metabolically expensive, and it seems likely that it shows some fairly steep diminishing returns in a subsistence farming environment -- particularly since its gains there are distributed over large populations. If a mutation gives you a chance of dying in a childhood famine and a much smaller chance of coming up with an agricultural innovation that might save your kids (and the rest of your village, but your mutation doesn't care) from dying of childhood famine, it's no advantage from a gene-centered point of view.
(On the other hand, if being good at Torah study is sexy in your subculture, then sexual selection might make up the difference.)
That's true comparing chimps to humans. I am not sure that's true comparing an IQ70 human to an IQ130 human.
Why wouldn't it be? Some of that increase might come from gains in efficiency, but precisely because brains are metabolically expensive, I'd expect most of the low-hanging efficiency gains in mammalian brains to be mined out already. Brute-force gains are limited by more than just energy, but I'd expect most architectural improvements to come with energy tradeoffs, too. When you get right down to it, something's got to do the computing.
Is there any evidence for it?
Is there any evidence against it? Not to play reference class tennis here, but given the choice between magic efficiency gains and continuing a curve that we can project out from the lower primates, the latter seems like the more reasonable null.
It seems like a relatively straightforward empirical question whether BMR correlates with IQ. I have no idea if it does, but maybe somebody who knows more neuroscience will chime in?
I would definitely expect metabolic cost to vary with brain size or neuron count or something, but AFAIK that varies relatively little between humans (compared to humans vs other primates). It's much less clear that better software or architecture is also more expensive.
No, not really. You can point to increased number of neurons, increased brain energy consumption, etc. for humans compared to primates very easily. I don't think you can point to the same thing for IQ130 humans compared to IQ70 humans. I don't have any hard data, but it doesn't seem to me that all the extra-smart people have unusually large heads and eat more than usual.
I don't buy the argument that the evolution must have optimized for intelligence already. The ability to e.g. hold a complicated structure in your mind wasn't particularly valuable for a pack of proto-humans in the African savannah.
Not optimized for intelligence, optimized for neural efficiency. Wikipedia tells me that most mammals devote single-digit percentages of BMR to brainpower, but for anatomically modern humans it's closer to 25%. Maybe more in childhood; Wikipedia doesn't say but the brain-to-body-mass ratio there is higher. When you've got an overambitious monkey burning a quarter of its calories keeping its freaky big monkey brain happy, there are very good reasons for evolution to explore all the corners that it can easily cut, as long as they don't exist in a state of ridiculous abundance. And since we know of at least one population bottleneck in the Paleolithic, I'm pretty sure food scarcity was a thing at that stage.
Did you look for any?
Quoted from here, the paper is here (they should have quoted the correlation of 0.38, which is what you get when you weight by sample size).
It's obvious that mental tasks do consume glucose. Jensen mentions metabolic correlations here, but not which direction they go in. This paper suggests that IQ and cerebral glucose metabolic rate are inversely correlated, and that after learning a new task more intelligent individuals showed larger decreases, but it looks like it has a very low n and I'd want to draw conclusions from review papers rather than individual investigations. I would not be surprised if the brain efficiency hypothesis dominates, and that higher IQ individuals get more bang for the buck instead of burning more to get more. I also hear more about cooling costs than calorie costs with regards to brain metabolism, but that may be because cooling costs fits with the observed data of smarter people evolving in colder places with higher latitudes.
Or, having access to paper and pen, it may actually be less valuable now than it was for a pack of proto humans. (The environment was pretty complicated even back then - competing tribes, complex network of alliances within a tribe, the habits of different animals, etc etc. But you couldn't put it down, you had to keep it all in your mind)
If there was no metabolic difference between building an IQ70 brain and an IQ130 brain, why would there be any effects from micronutrient deficiency?
Remember, expensive isn't limited to adult basal metabolic rates, there are other ways to be expensive; for example, a better brain could suck up tons of iron, iodine, and protein in childhood, requiring lots of meat and fat and seafood, and if a fetus or child's metabolic needs are not met, whups, there goes some myelination (fat), some non-cretinism (iodine), some energy and lassitude (iron and protein)...
Also cranial capacity is in fact correlated to iq
Well, hypothetically, if we have a chip fab, and it has a "micronutrient deficiency", it can produce noisier circuits that don't consume less power, or which would even consume more power.
It would seem that there are some basic requirements which need to be met to build the brain correctly, requirements that are proportional to the brain volume, with no gains from exceeding those requirements. One could further hypothesise that those requirements are met in almost all "IQ130" brains.
Sure. Chip fabs probably even have 'micronutrient deficencies' in a very similar way - if you can't get enough of the exact right exotic element or mineral for say doping semiconductors, the engineers can probably work around it but won't get as power-efficient or fast a chip. (Now I'm imaging correlating chip fab 'brain damage' to global commodity prices...)
I don't think deficiency in dopants can ever arise, though, as they're used in incredibly tiny amounts.
For micro-nutrient deficiencies the issue is often not so much with obtaining the micronutrient as with the lack of craving for it. We can smell iodine, but we don't crave it when deficient, so we didn't have seaweed and the like as a high value spice which everyone craves.
But they need to be extremely pure and in the right form to be used. (If just having the raw material was enough, no one would ever die of thirst drinking salt-water and plants would never lack for nitrogen.)
Maybe we can smell very large quantities of iodine, but can one really smell deficiency-relevant amounts in seaweed?