5 ms·

Even if we can't measure it, what makes it so hard to believe that intelligence is inheritable? Is height inheritable? Yes. Is eye color inheritable? Yes. Is sk

by honm 16y ago

Even if we can't measure it, what makes it so hard to believe that intelligence is inheritable? Is height inheritable? Yes. Is eye color inheritable? Yes. Is skin color inheritable? Yes. Is physical strength....? Yes. Why wouldn't a human characteristic that has provided one of the biggest advantages through evolution not be inheritable too?

Almaviva 16y ago
What if we postulate a general factor "b" that correlates with a superior body, is that inheritable? It's not that certain characteristics of the brain aren't inheritable, it's that "intelligence" is very diffuse and hard to define. It's not even so clear that what many of us would call intelligence is mainly an evolutionary advantage, either.
Symmetry 16y ago
The author isn't saying that intelligence isn't heritable. He just showed that we can measure heritability in things that don't exist (the sum of a persons weight and height in some units) as well as things that exist like their actual weight and height. Therefore, the fact that g is heritable doesn't mean that its a thing that exists. Except I think the author would point out that there isn't just _one_ heritability for things like height because height would be much more heritable in environments where everyone has adequate nutrition as opposed to in environments where nutrition was a matter of luck, for instance. All of this assumes a certain philosophical veiwpoint on what it means to "really exist" which I don't agree with, but which I do recognize as coherent.
ramses 16y ago
Because that would contradict their political ideology.
- honm 16y ago
  Yes, I think that might be it. Unfortunately, there isn't much evidence any side can put on the table. Genetics will advance a lot in the coming years, so that might put an end to the debate and that ideology will be shattered. If that same ideology impedes that we study heritability in the West, I'm sure China will still study it.
Groxx 16y ago
Is height entirely inherited? No, diet makes extraordinary differences. Is physical strength entirely inherited? No, exercise builds muscle. There are of course factors on both sides, but for mental / physical strength I'll happily argue for landing waaaay towards the what-you-do-with-it, not-what-you-have side.
- honm 16y ago
  Where I live you honestly can't say that diet stunts people's growth. That would apply in places where food isn't readily available, but certainly not in the western world. From looking at people I know I can tell you too, that the differences in muscle size is more related to how much muscle they had before going to the gym than how much time they spend there. Can you start going to the gym and get stronger than your friends who don't go? No. Out of 10 friends maybe you'll pass 1 or 2 of them in strength, but that's it. That is what I have seen but I'd say it is pretty far from what you suggest.
  - tygorius 16y ago
    Can you start going to the gym and get stronger than your friends who don't go? No. Presumably your circle of friends consists of people who are already physically active. Even so, I doubt your assessment concerning strength training. Looking at the people around me, I'm guessing fewer than 5% (not 80%) of them are up to 100 pushups [http://www.hundredpushups.com/ http://www.hundredpushups.com/]
  - Groxx 16y ago
    You presume a) everyone has access to healthy food as kids, and b) strength training is nearly ineffective. What, you forgot about the massive population of poor the world has, western included? Or how many in the western world eat crap, because it's easier than making things for ourselves? Height is largely determined by what your parents feed you, once you're able to be on your own you're essentially fully grown. I know a decent number of people whose parents were either relatively poor, and they subsisted on mac & cheese frequently, or were largely idiots when it came to food and raising kids. And many of them are noticeably shorter than average. My wife, for instance, is just barely over 5 feet, and her family-then-single-father fell into both categories until he joined the military. As to the second... I have absolutely no idea where you get that idea from. Maybe everyone around you weight-trains outside of the gym frequently, or you've never done so for an extended period of time? You're absolutely nuts, though.
tokenadult 16y ago
The example of the German monozygotic twins Otto and Ewald, both well nourished but sportsmen who pursued different sports, show that physique is exquisitely sensitive to environmental influences even between two individuals who share a genome and a prenatal environment in the same mother's womb. Take a look at the photos. http://www.marksdailyapple.com/control-gene-expression/ http://www.marksdailyapple.com/control-gene-expression/ http://www.joebower.org/2010/05/we-inherit-and-we-also-become.html http://www.joebower.org/2010/05/we-inherit-and-we-also-becom... AFTER EDIT: I'm asked in a reply below what my point was, and it's partly to point out that the term "heritable" means something far, far different from "determined by genes." There are whole books http://www.amazon.com/Nature-Nurture-Environmental-Influences-Development/dp/0805843876 http://www.amazon.com/Nature-Nurture-Environmental-Influence... http://www.amazon.com/Genes-Behavior-Nature-Nurture-Interplay-Explained/dp/1405110619/ http://www.amazon.com/Genes-Behavior-Nature-Nurture-Interpla... http://www.amazon.com/Dependent-Gene-Fallacy-Nature-Nurture/dp/0805072802/ http://www.amazon.com/Dependent-Gene-Fallacy-Nature-Nurture/... by professional geneticists, medical doctors, and psychologists patiently refuting the confusion in most popular literature about what "heritability" means, but the main point in this thread is that Shalizi is correct, and many psychologists are wrong, about what heritability figures mean in relation to IQ.
- xiaoma 16y ago
  Not really sure what your point is there. It's natural two people with virtually identical genes subjected to vastly different training would have different body-types. It's also natural that two people with vastly different genes would respond differently to virtually identical training. Consider someone like this boy vs his classmates: http://www.sciencentral.com/articles/view.php3?type=article&article_id=218392292 http://www.sciencentral.com/articles/view.php3?type=article&...

by honm 16y ago

Almaviva 16y ago

What if we postulate a general factor "b" that correlates with a superior body, is that inheritable? It's not that certain characteristics of the brain aren't inheritable, it's that "intelligence" is very diffuse and hard to define. It's not even so clear that what many of us would call intelligence is mainly an evolutionary advantage, either.

Symmetry 16y ago

The author isn't saying that intelligence isn't heritable. He just showed that we can measure heritability in things that don't exist (the sum of a persons weight and height in some units) as well as things that exist like their actual weight and height. Therefore, the fact that g is heritable doesn't mean that its a thing that exists. Except I think the author would point out that there isn't just _one_ heritability for things like height because height would be much more heritable in environments where everyone has adequate nutrition as opposed to in environments where nutrition was a matter of luck, for instance. All of this assumes a certain philosophical veiwpoint on what it means to "really exist" which I don't agree with, but which I do recognize as coherent.

ramses 16y ago

Because that would contradict their political ideology.

honm 16y ago
Yes, I think that might be it. Unfortunately, there isn't much evidence any side can put on the table. Genetics will advance a lot in the coming years, so that might put an end to the debate and that ideology will be shattered. If that same ideology impedes that we study heritability in the West, I'm sure China will still study it.

Groxx 16y ago

Is height entirely inherited? No, diet makes extraordinary differences. Is physical strength entirely inherited? No, exercise builds muscle. There are of course factors on both sides, but for mental / physical strength I'll happily argue for landing waaaay towards the what-you-do-with-it, not-what-you-have side.

honm 16y ago
Where I live you honestly can't say that diet stunts people's growth. That would apply in places where food isn't readily available, but certainly not in the western world. From looking at people I know I can tell you too, that the differences in muscle size is more related to how much muscle they had before going to the gym than how much time they spend there. Can you start going to the gym and get stronger than your friends who don't go? No. Out of 10 friends maybe you'll pass 1 or 2 of them in strength, but that's it. That is what I have seen but I'd say it is pretty far from what you suggest.
- tygorius 16y ago
  Can you start going to the gym and get stronger than your friends who don't go? No. Presumably your circle of friends consists of people who are already physically active. Even so, I doubt your assessment concerning strength training. Looking at the people around me, I'm guessing fewer than 5% (not 80%) of them are up to 100 pushups [http://www.hundredpushups.com/ http://www.hundredpushups.com/]
- Groxx 16y ago
  You presume a) everyone has access to healthy food as kids, and b) strength training is nearly ineffective. What, you forgot about the massive population of poor the world has, western included? Or how many in the western world eat crap, because it's easier than making things for ourselves? Height is largely determined by what your parents feed you, once you're able to be on your own you're essentially fully grown. I know a decent number of people whose parents were either relatively poor, and they subsisted on mac & cheese frequently, or were largely idiots when it came to food and raising kids. And many of them are noticeably shorter than average. My wife, for instance, is just barely over 5 feet, and her family-then-single-father fell into both categories until he joined the military. As to the second... I have absolutely no idea where you get that idea from. Maybe everyone around you weight-trains outside of the gym frequently, or you've never done so for an extended period of time? You're absolutely nuts, though.

tokenadult 16y ago

The example of the German monozygotic twins Otto and Ewald, both well nourished but sportsmen who pursued different sports, show that physique is exquisitely sensitive to environmental influences even between two individuals who share a genome and a prenatal environment in the same mother's womb. Take a look at the photos. http://www.marksdailyapple.com/control-gene-expression/ http://www.marksdailyapple.com/control-gene-expression/ http://www.joebower.org/2010/05/we-inherit-and-we-also-become.html http://www.joebower.org/2010/05/we-inherit-and-we-also-becom... AFTER EDIT: I'm asked in a reply below what my point was, and it's partly to point out that the term "heritable" means something far, far different from "determined by genes." There are whole books http://www.amazon.com/Nature-Nurture-Environmental-Influences-Development/dp/0805843876 http://www.amazon.com/Nature-Nurture-Environmental-Influence... http://www.amazon.com/Genes-Behavior-Nature-Nurture-Interplay-Explained/dp/1405110619/ http://www.amazon.com/Genes-Behavior-Nature-Nurture-Interpla... http://www.amazon.com/Dependent-Gene-Fallacy-Nature-Nurture/dp/0805072802/ http://www.amazon.com/Dependent-Gene-Fallacy-Nature-Nurture/... by professional geneticists, medical doctors, and psychologists patiently refuting the confusion in most popular literature about what "heritability" means, but the main point in this thread is that Shalizi is correct, and many psychologists are wrong, about what heritability figures mean in relation to IQ.

xiaoma 16y ago
Not really sure what your point is there. It's natural two people with virtually identical genes subjected to vastly different training would have different body-types. It's also natural that two people with vastly different genes would respond differently to virtually identical training. Consider someone like this boy vs his classmates: http://www.sciencentral.com/articles/view.php3?type=article&article_id=218392292 http://www.sciencentral.com/articles/view.php3?type=article&...