Comment by Xirdus | Hacker News Reader

Comment by Xirdus | Hacker News Reader

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> So why do you believe someone with 180 IQ is that much smarter than 100, if you agree there are no metrics to back it up?

Because that's how it works for most other learnable, trainable skills that aren't dependent on physical limits of the body, and I don't see why intelligence would be any different. Yes I'm still saying intelligence isn't physical.

I know IQ is (used to be?) age-adjusted. I wasn't talking about IQ there, I'm talling about raw intelligence. Child prodigies beat adults at chess, at maths, at programming, you name it - and it's happening way more commonly than head/brain size variation would allow for it.

I never said entirely trained. For somebody who just spent 10 whole paragrahs across 3 comments (+/- 50%, like I said I wasn't really reading) chastising me for not reading carefully, you sure fumbled this one.

Think of intelligence like playing piano. Most people can't play piano. But most people can learn to play piano, to some extent. How good they are depends mostly on how much they've been learning, but everyone has some point they just can't push past through no matter how much they try. Usually that point is pretty low, way before the general audience is willing to pay for watching. For a tiny minority, that ceiling is much higher and the growth they get from practice is much faster too - we call these people talented or naturally gifted.

And then there are the piano prodigies who absolutely shred the keyboard at the age of 5. There are enough of them that you can't explain it away with abnormal growth of any relevant body organ. That's what I mean when I say head circumference variation is too small in children to explain the number of child geniuses, if intelligence is entirely biological.

IQ measures whatever intelligence happens to be. It's just an assumption that the kind of intelligence that helps with IQ tests is entirely biological, and only under that assumption IQ measures the biological component only. But that assumption is likely wrong, considering you can train to score better at IQ tests (it's a fact). Either intelligence isn't biological, or IQ metric sucks at isolating the biological component - feel free to assume the latter.

Oh you misunderstood me; I wasn't making any claims about what you said, I was only pointing out the logical conclusion that measuring acquired skills is not measuring intelligence, it would only be measuring effort & interest. I'm trying to point out why the training part of IQ or intelligence is the far less interesting part. The more trainable it is, the more nobody cares. What many people want to know is what's the capacity for intelligence; what's the ceiling on training. Think about it: the single most valid and important use case for intelligence testing is deciding how to adapt the educational curriculum for children.

BTW I'm not the one repeatedly bringing up the 20% thing, I'm trying to drop it.

You are arguing that intelligence is primarily trained and not primarily a physical trait, no? You did make a claim about a two orders of magnitude intelligence difference between IQs of 180 and 100, right? You seem to agree that "intelligence" is a combination of genetics and training, is that correct? And you believe the variance in IQ scores is mostly due to training and not genetics, or what?

This is somewhat going in circles now. I've agreed multiple times that IQ scores are somewhat trainable, and you're ignoring the facts that 1) it's only a little bit trainable not a lot, and 2) that people generally tend to have a stable IQ measurement over their lifetime (adults moreso than kids), and 3) that the goal of IQ tests is to try to factor out training to some degree, which is why it used to divide by age and now measures only rank. Cultural bias was a huge a valid criticism of earlier IQ tests, and they've taken steps to avoid relying on knowledge.

I'd certainly love to hear a more interesting argument or any evidence at all for you two orders of magnitude claim, but I can accept you're telling me your opinion and not something defensible. What we have agreed on is that IQ doesn't measure intelligence, it measures rank. One way or another, that fact could fully explain the outcome of the article we're commenting on.

> Child prodigies beat adults at chess, at maths, at programming, you name it.

FWIW, that's not really true in any meaningful way, and to some degree it contradicts what you're saying about training intelligence. The child outliers are not beating the adult outliers. Some children can outperform the average adult, but what has that got to do with anything? Some adults can also outperform the average adult. If children are outperforming adults, and they've had less training time, then how do you explain the superior performance? What is a naturally gifted child prodigy, if not evidence of physical traits?

> You are arguing that intelligence is primarily trained and not primarily a physical trait, no?

No I'm not. Not as stated.

You are correct in that the more trainable intelligence is, the less people care about IQ. Coincidentally, people's caring about IQ has been falling drastically the last couple decades.

> What is a naturally gifted child prodigy, if not evidence of physical traits?

It's evidence that it's not a physical trait at all. At least not the kind that scales with size (and therefore would have a relatively narrow variance among adults with both the median and the modal value in the dead center between 3rd and 97th percentile, while undergoing a massive change around the time of puberty, so much so that reaching average post-puberty score before puberty is near impossible).

Obviously everything ultimately comes down to neural connections powering the brain. Knitting, bull riding and playing piano are just as much physical attributes as intelligence. We live in a physical world after all. But that makes the term "physical trait" quite useless. So instead, I'm choosing to interpret physical trait as anything that is almost entirely determined by measurable aspects of a person's physical body. And intelligence just isn't it.

Did you mean to say "intelligence is primarily genetic" instead? That I would agree with.

> Did you mean to say “intelligence is primarily genetic” instead? That I would agree with.

Perhaps I did mean to say child prodigies are evidence of the heritability of intelligence; that it suggests intelligence has a large, possibly majority, genetic component, if kids are outliers without much training.

Okay, so you’ve been objecting to ‘physical traits’ but agree with ‘genetic’… What is the difference in your mind between those? I see them as, broadly speaking, the same thing. Physical traits are phenotypes, no? Genetics is the biological component I’ve been talking about all along, and heritability is defined as that which is genetic, i.e., not explained by the environment or chance, i.e., not due to training.

Knitting, bull riding, and playing piano are neither intelligence, nor are they physical attributes. They are learned skills. It seems some people may have genes that may help them learn these skills faster than other people, but these are not ‘physical traits’ in any way shape or form, and your commentary on that term isn’t making sense to me right now. If you think piano playing is a ‘physical trait’, that could explain much of the miscommunication in this thread.

But musical skills are largely genetic. https://pmc.ncbi.nlm.nih.gov/articles/PMC4073543/

I still refuse to call playing piano a physical trait.

I must have misunderstood you above, we completely agree there; piano playing is not a physical trait.

We are finally getting somewhere, it’s too bad this got too deep before finding a basis for productive conversation. The paper you linked is very interesting, I would just note that your strong claim with the qualifier “largely” in your statement is not supported by the paper. The paper does not demonstrate musical skills are primarily or ‘largely’ genetic, it only suggests there may be some heritability of music perception. At least some of genes it mentions are nothing more than hearing anatomy, so of course they affect music, but they also affect basic speed and any audio. It’d be wise to not overstate what that paper is saying.

I could link to a bunch more studies that find more direct genetic links to musical aptitude in particular rather than musical perception in general. But I'd rather skip the busy work and jump straight to the point where we both agree to the following.

1. Musical talent is hereditary to a significant degree.

2. Musical talent is NOT a physical trait.

3. Therefore, being hereditary is not a proof of being a physical trait, despite the literal physical differences in DNA sequence.

Deal?

#1 is not a justifiable statement as written, #2 is true, #3 needs better terminology. Genetics does determine physical traits (physical traits are defined as phenotypes), heredity is about genetic variation. If you agree musical ability or intelligence are significantly genetic, then it follows that musical ability or intelligence must be attached to, associated with, or correlated with physical traits of some kind.

In light of your acceptance of intelligence having a significant genetic component, I wanted to re-evaluate the discussion from the top. You pushed back on my attempts to discuss genetics and made strong claims about training being important for intelligence, and now you’re making strong claims about genetics being important. I don’t know where that leaves us. My original point, recall, was that genetic variation doesn’t support the popular high-IQ narrative of so called super geniuses. Genetics cannot explain your claim of 100x difference in intelligence, and the only thing we’ve talked about that does explain it is training, which is not genetic, and, we both agree, boring.

There is a world of difference between "is a physical trait" and "is attached to, associated with, or correlated with physical traits". The way I see it, saying that intelligence is correlated with physical body features is admitting that intelligence is not a physical trait itself after all.

The first reason I insist on the difference is because absolutely everything indirectly depends on physicality of the biological body. Spirituality aside, there isn't a single thing about humans that doesn't depend on the shape or size or chemistry or electrical charge of something somewhere. This makes "physical trait" an utterly useless category, one that clearly includes playing piano, and I really don't like that.

The second reason I insist on the difference is because the correlation doesn't have to be linear. There's no reaso why it can't be quadratic or logarithmic or exponential or hyperbolic or whatever. Being a literal physical feature imposes normal distribution with tight variance. Merely being correlated does not. If you still want to argue geniuses are not that much more intelligent than average people, you'd need more evidence than simple hereditability.

When you say "intelligence is a physical trait", I hear "there is a part of parts of the brain that have a certain total volume/mass/density/number of neurons/synapses/neural pathways/etc., and that number is the literal definition of intelligence". It's how it works for every other thing that we call a physical trait. If you didn't mean it like that, maybe you should have used a different terminology from the get go.

Now excuse me while I go looking for 10-15 more citations on the genetic component of musical ability that you're definitely not going to dismiss as irrelevant for one reason or another.

It seems like you maybe missed the part in the middle of the thread where I said you’re right about IQ scores and what we call intelligence not being a so called physical trait. I’m not arguing that at this point and haven’t been for a while, because it became clear we are talking about different things. I’m looking for more mature terminology at this point, established phrases and concepts we can agree on, because this is too sloppy of a discussion. You’re making assumptions and jumping to a weird conclusion about what ‘physical traits’ means and I don’t agree that it’s useless, other than that the term has somewhat poisoned this discussion and is preventing progress. Physical traits are phenotypes, and phenotypes are an extremely useful notion in a discussion of genetics vs environment vs chance.

Your statement about correlation being an admission of not being a physical trait sounds naive to me; it’s ignoring the existence of polygenic traits.

Another source of terminology confusion here is the difference in what we mean by ‘intelligence’, and it’s probably way more important than what ‘physical attribute’ means. I really meant something different by ‘intelligence’ than you mean, and that’s my fault for not clarifying I was trying to focus on heritability and factor out learned skill.

I would love to see additional references about music and heredity, I’m looking forward to it.

You know you both have been locked in this unproductive 2-person thread for days now right?

It wasn't unproductive at all! Can't you see we just about worked out a consensus?

OK, ok, my bad, carry on! :)

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