# Inherited Intelligence **URL:** \ **Category:** Factual Questions\ **Created:** [December 28, 1999, 4:19am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807 "1999-12-28T04:19:00Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![rjk](https://avatars.discourse-cdn.com/v4/letter/r/ed655f/32.png) [@rjk](https://boards.straightdope.com/u/rjk)\ **Post date:** [December 30, 1999, 11:55pm UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/21 "1999-12-30T23:55:00Z")
I just finished rereading “The Mismeasure of Man” by Stephen Jay Gould, a discussion of the many problems with IQ testing. He comes to a couple of relevant conclusions. First, there doesn’t seem to be good evidence for some quality of “general intelligence”; his remarkably clear explanation of factor analysis (the statistical method invented to demonstrate IQ!) shows that a multiple-abilities model is mathematically just as good. What we call IQ may just be an average of many different talents. Second, he says that the “nature-vs-nurture” debate is pointless because we develop as a result of complex interactions among many genetic and environmental factors, not the simple balance of forces implied by statements like “It’s 80% genetic!” or “It’s 80% environmental!”. * * * Bob the Random Expert “If we don’t have the answer, we’ll make one up.” ---
**Author:** ![Avumede](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/avumede/32/7235_2.png) [@Avumede](https://boards.straightdope.com/u/Avumede)\ **Post date:** [December 31, 1999, 12:08am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/22 "1999-12-31T00:08:00Z")
Just a few quick points: Children whose parents have very low IQ’s (70’s), can achieve tramatic results (as, IQ’s above 100) by being in a very stimulating environment from an early age. The same seems to happen for those with average parents, but to a much less extent. Also, being in school raises your IQ a few points. IQ will actually tend to drop after a summer vacation. We all know it’s true, don’t deny it! ---
**Author:** ![dlv](https://avatars.discourse-cdn.com/v4/letter/d/5f9b8f/32.png) [@dlv](https://boards.straightdope.com/u/dlv)\ **Post date:** [December 31, 1999, 12:09am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/23 "1999-12-31T00:09:00Z")
> [@](#): > > I just finished rereading “The Mismeasure of Man” by Stephen Jay Gould, a discussion of the many problems with IQ testing. I’m sorry that you wasted your time on this book. Mr. Gould has no credibility. You’re better off (re)reading the comic strips. ---
**Author:** ![rjk](https://avatars.discourse-cdn.com/v4/letter/r/ed655f/32.png) [@rjk](https://boards.straightdope.com/u/rjk)\ **Post date:** [December 31, 1999, 12:10am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/24 "1999-12-31T00:10:00Z")
## And of course I should say that many of the posters above raise points mentioned in the book: Diceman, glee, Jois, Moonshine, and Triskadecamus. Bob the Random Expert “If we don’t have the answer, we’ll make one up.” ---
**Author:** ![rjk](https://avatars.discourse-cdn.com/v4/letter/r/ed655f/32.png) [@rjk](https://boards.straightdope.com/u/rjk)\ **Post date:** [December 31, 1999, 12:13am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/25 "1999-12-31T00:13:00Z")
> [@](#): > > Mr. Gould has no credibility. Credibility with whom? Can you point us to some critique? * * * Bob the Random Expert “If we don’t have the answer, we’ll make one up.” ---
**Author:** ![Revtim](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/revtim/32/1042_2.png) [@Revtim](https://boards.straightdope.com/u/Revtim)\ **Post date:** [December 31, 1999, 2:59am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/26 "1999-12-31T02:59:00Z")
Perhaps the question can be resolved by asking, “are there genes/chromosomes that a child, male or female, always gets from only the mother?” I would guess no, but I don’t really know. (I think the DNA of the cellular mitochodria always comes from the mother, but I seriously doubt that has anything to do with intelligence). If someone can comfirm that there is no genetic material that always exclusively comes from the mother, then I think that would disprove the idea that intelligence (or anything, for that matter) always comes from the mother. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [December 31, 1999, 4:45am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/27 "1999-12-31T04:45:00Z")
Any “twins separated at birth” studies still can’t differentiate between genetic effects and effects due to the environment in the womb. The September 27, 1999 issue of Newsweek has an article on this, mostly focused on health effects, like how prenatal conditions are associated with diseases later in life. They only had a little bit on intelligence, beginning with “Research on how life in the womb influences the brain is only beginning.” I also recall reading or seeing on TV recently (sorry, no cite) that childhood (maybe only for girls?) lead exposure can cause depressed intelligence in **their** children. ## Yikes. _It is too clear, and so it is hard to see._ ---
**Author:** ![Konrad](https://avatars.discourse-cdn.com/v4/letter/k/f475e1/32.png) [@Konrad](https://boards.straightdope.com/u/Konrad)\ **Post date:** [January 2, 2000, 4:12am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/28 "2000-01-02T04:12:00Z")
It’s silly to say intelligence can only be inherited from one parent. There are so many genes that affect how your brain works that it’s almost impossible they’d all be on the tail end of the X-chromosome. (The only way something can be only inherited from the mother is if it’s located on the X-chromosome). It’s not like genes are that organized in the first place. There’s no “thinking department” or “beauty department” in our genes. It’s possible that more of your intelligence comes from your mother but it would have to be something specific, like the development of a certain part of the brain. Maybe something like spatial perception, but even that is unlikely. What is likely is that many defects that cause mental problems could be coded on the X-chromosome and therefore dependent on the mother. Maybe that’s what your doctor friend was talking about. ---
**Author:** ![dlv](https://avatars.discourse-cdn.com/v4/letter/d/5f9b8f/32.png) [@dlv](https://boards.straightdope.com/u/dlv)\ **Post date:** [January 2, 2000, 5:03am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/29 "2000-01-02T05:03:00Z")
> [@](#): > > Can you point us to some critique? Better yet, I can point you to John B. Watson’s _Behaviorism_ (p.104): > [@](#): > > Give me a dozen healthy infants, well formed, and my own specified world to bring them up in and I’ll guarantee to take any one at random and train him to become any type of specialist I might select - doctor, lawyer, artist, merchant-chief and, yes. even beggar-man and thief, regadless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestors. I am going byond my facts and I admit it, but so have the advocates of the contrary and they have been doing that for many thousands of years. Please note that when this experiment is made I am to be allowed to specify the way the children are to be brought up and the type of the world they have to live in. Orthodox Marxists (such as Mr. Gould) are supposed to believe that intelligence is 100% acquired and 0% inherited. Do you believe that? ---
**Author:** ![tomndebb](https://avatars.discourse-cdn.com/v4/letter/t/b9e5f3/32.png) [@tomndebb](https://boards.straightdope.com/u/tomndebb)\ **Post date:** [January 2, 2000, 5:41am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/30 "2000-01-02T05:41:00Z")
**dlv** : > [@](#): > > Orthodox Marxists (such as Mr. Gould) are supposed to believe that intelligence is 100% acquired and 0% inherited. Do you believe that? So your critique of Dr. Gould is based on what someone told you his political beliefs are _supposed_ to dictate to him? Sorry. I have disagreed with several conclusions that Gould has drawn and published, but your statements require something better than a leap from a hypothetical belief of what he _should_ propose to what you want him to have said. You have stated that he has _no_ credibility. You have provided no clearly erroneous conclusion that he has drawn and no criticism by any authority that can be shown to demolish Gould’s positions. * * * Tom~ ---
**Author:** ![rjk](https://avatars.discourse-cdn.com/v4/letter/r/ed655f/32.png) [@rjk](https://boards.straightdope.com/u/rjk)\ **Post date:** [January 3, 2000, 3:27am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/31 "2000-01-03T03:27:00Z")
Thanks, Tom, I couldn’t have said it better. (OK, probably not half as well!) ## In any case, dlv, my post wasn’t anything like Watson’s claim. Try rereading the second point. Bob the Random Expert “If we don’t have the answer, we’ll make one up.” ---
**Author:** ![dlv](https://avatars.discourse-cdn.com/v4/letter/d/5f9b8f/32.png) [@dlv](https://boards.straightdope.com/u/dlv)\ **Post date:** [January 3, 2000, 3:57am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/32 "2000-01-03T03:57:00Z")
This is pointless. ---
**Author:** ![Cooper](https://avatars.discourse-cdn.com/v4/letter/c/50afbb/32.png) [@Cooper](https://boards.straightdope.com/u/Cooper)\ **Post date:** [January 3, 2000, 6:21am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/33 "2000-01-03T06:21:00Z")
Glee: I’m not sure I saw where you disagreed with me. Basically you expressed frustration that what people mean by ‘intelligence’ is not better understood, defined and articulated. Well, to a degree I share this frustration. If it is your contention that IQ tests do not tell us anything relevant about a person’s intelligence, then I disagree. ---
**Author:** ![NanoByte](https://avatars.discourse-cdn.com/v4/letter/n/ecc23a/32.png) [@NanoByte](https://boards.straightdope.com/u/NanoByte)\ **Post date:** [January 3, 2000, 9:08am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/34 "2000-01-03T09:08:00Z")
13er, in re the definition of intelligence: Psychology, by definition, can **never** be a(n objective) science. The mind is not the brain. Moonshine, as to same: > [@](#): > > . . .the working definition we used was that intelligence was what an IQ test measured. This works just fine for most discussions, . . . I guess that’s why I take “most discussions” with a grain of salt. That’s like saying the amount of gasoline in your tank is whatever your gas gauge says. So when you run out of gas, all you have to do is feed the gauge a little more current from your battery, and thereby save money at the pump. I was a member of [Mensa[/url"] for a while. They really believed those tests put them somewhere. I really wasn’t convinced; most were pretty phony. Some believed in a mystical [url=http://www.webcom.com/zurcher/thegfactor/about.html]‘g’ factor](http://www.us.mensa.org/). One guy there even designed his own IQ test and got it published in Omni Magazine quite some time ago, thereafter selling results of their mailed-in tests based on it to Omni readers. . .until the USPS got after him for not delivering the test results in a reasonable time. Seems to me those tests mostly measure a sort of ego. . .whatever **that** is. It’s a nice game to play, I guess. > [@](#): > > its not intelligence itself that is being discussed, but the differences between people, and between people and animals or computers. You actually believe existing IQ tests test “the difference” between people, animals and computers? The difference in what? I mean, a camera hooked up to a pattern-recognition program can measure differences in these things, can it not? How does your dog do on the Wechsler or Stanford-Binet anyhow? Which is brighter, a PC or a Mac. . .or a 100-w light bulb? I think the latter could “shed more light”. . . I fail to see the difference in the degree of value of IQ tests dependent on whether the test is testing 1) “intelligence” or 2) testing the relative effects of nature versus nurture **on** intelligence. Jois: The subject is intelligence, not how to be politic. Say, BTW, what does your dog charge for medical consultations? I don’t have one. 😉 ‘Intelligence’ is a subjective concept, as we apply it to humans; it **can’t** have meaning in the realm of scientific objectivity. Genome is when you finally get to the end of the Iditarod Trail. Cooper, as to what intelligence is: How do you know “John” isn’t in a class of mentally challenged folks who experience intelligent people as stupid? Yeah, OK, well, whatever I say here **must** be “consistent with vague opinions” of **somebody**. 😉 The one back there who mentioned that the twin didn’t go to Uzbekistan: It seems to me that, if you raise one twin in a very abnormally uninstimulating environment, you’re doing a very different test than one in which you raise that one in an equally stimulating but very **different** environment from the other twin, but I’ve forgotten what the measure of difference was. Was it only “intelligence”, as measured by one or more certain intelligence tests? glee: I think you have something to put Mensa out of business – charisma tests. I mean, the that’s more or less what the media operate with, isn’t it? If you advertise on them, you can outnumber Mensans overnight! Shirley Uj: Well, I never took “physcology”, but that word you use, ‘coworkers’, always bothers me. Nobody ever tells me how one orks a cow. How exactly is that done? Now, professors. . .if you want to be professed to, OK. . .but the truth may lie elsewhere. Jois on schooling and testing: In junior high I once had an English teacher, who, upon finding out that I did well in other subjects, gave me an F for work I would’ve otherwise been given a C. (Well, having been caught reading a math book in her class once didn’t help either.) I had a like regard of history teachers. In high school, I couldn’t stand the egotism of one, which upon some clashing, resulted in my advisor substituting study hall for me. English and history teachers are dements, period. 😉 Avumede: I like your word ‘tramatic’ – a cross between ‘dramatic’ and ‘traumatic’, I guess. I used to drop my IQ once in a while. It used to bounce, but the years have now made it a bit soggy. rjk: Those who make up the answer don’t **need** any IQ. I mito- had a -chondria once, but I think I left it in my other jeans. dlv, on Watson: So, Watson left out engineers. Doctors and lawyers are not specialists; they’re just fast talkers. You can’t make inanimate matter do what you want and give you money just by talking to it. (Spoken by an retired engineer.) Ray (My other self is not a twin.) ---
**Author:** ![NanoByte](https://avatars.discourse-cdn.com/v4/letter/n/ecc23a/32.png) [@NanoByte](https://boards.straightdope.com/u/NanoByte)\ **Post date:** [January 3, 2000, 9:17am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/35 "2000-01-03T09:17:00Z")
Damn! I though I could get by with UBB URLs if they were short. No way. Those things are totally fouled up. In my last post, where there is a long link, there were supposed to be two. They are: [Mensa](http://www.us.mensa.org/) and [g factor](http://www.webcom.com/zurcher/thegfactor/about.html) Ray ---
**Author:** ![Lucretia](https://avatars.discourse-cdn.com/v4/letter/l/13edae/32.png) [@Lucretia](https://boards.straightdope.com/u/Lucretia)\ **Post date:** [January 4, 2000, 3:27am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/36 "2000-01-04T03:27:00Z")
A pschycologist friend of mine once told me about something called “reversion to the mean”, where the children of super-intelligent parents tended to be average or only slightly above average in intelligence, instead of overwhelmingly geniuses themselves, as you might expect if intelligence had a major inheritance component to it. ---
**Author:** ![Jois](https://avatars.discourse-cdn.com/v4/letter/j/ea666f/32.png) [@Jois](https://boards.straightdope.com/u/Jois)\ **Post date:** [January 4, 2000, 7:03am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/37 "2000-01-04T07:03:00Z")
Nanobyte said:In junior high I once had an English teacher, who, upon finding out that I did well in other subjects, gave me an F for work I would’ve otherwise been given a C. (Well, having been caught reading a math book in her class once didn’t help either.) Well, teachers of 6th, 7th, & 8th grades often voice the opinion that school should recess after 5th grade and not resume until 9th. There is a certain unloveliness about kiddies that age or so they say. Gifted teachers for that same age group feel that money and resources could be put to better use, again by omitting services to that age group. However I’m sure you were lovely and quite undeserving of that F. ---
**Author:** ![NanoByte](https://avatars.discourse-cdn.com/v4/letter/n/ecc23a/32.png) [@NanoByte](https://boards.straightdope.com/u/NanoByte)\ **Post date:** [January 4, 2000, 9:42am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/38 "2000-01-04T09:42:00Z")
As I recall, my adviser got me out of that one two, I think. > [@](#): > > There is a certain unloveliness about > kiddies that age or so they say. I’d say they end up getting teachers for that age group that are a good match. 😉 Yeah, I wasn’t roudy at all, just not a budding author. Ray (How I Wasted my Summer Vacation on a Dark and Stormy Night) ---
**Author:** ![NanoByte](https://avatars.discourse-cdn.com/v4/letter/n/ecc23a/32.png) [@NanoByte](https://boards.straightdope.com/u/NanoByte)\ **Post date:** [January 4, 2000, 9:45am UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/39 "2000-01-04T09:45:00Z")
How **could** I have been rowdy if I couldn’t even spell it? Ray ---
**Author:** ![dlv](https://avatars.discourse-cdn.com/v4/letter/d/5f9b8f/32.png) [@dlv](https://boards.straightdope.com/u/dlv)\ **Post date:** [January 4, 2000, 2:10pm UTC](https://boards.straightdope.com/t/inherited-intelligence/5807/40 "2000-01-04T14:10:00Z")
> [@](#): > > A pschycologist [sic] friend of mine once told me about something called “reversion to the mean”, where the children of super-intelligent parents tended to be average or only slightly above average in intelligence, instead of overwhelmingly geniuses themselves, as you might expect if intelligence had a major inheritance component to it. The problem with orthodox Marxists (like Mr. Gould) and left-wingers in general is that they prefer to describe about their vision of the world according to their theories/political views, as opposed to pracical experiments and real-world observations. Numerous studies found a very strong correlation between parents’ IQ and children’s IQ (even in situations where the children were adopted and raised by adoptive parents with a different IQ). There’s also very strong correlation between monozygotic (identical) twins adopted and raised separately. You can find references, e.g., in the infamous _Bell Curve_. The PC crowd (such as Mr. Gould) are not happy with these studies primarily because they also showed a material difference in the average IQ of different races (Asians on the average scored higher on IQ tests than whites, who in turn showed higher IQ than blacks). They label these findings “racist” and assert than IQ has nothing to do with “intelligence” and/or that there’s no such thing as “intelligence”. To paraphrase Mr. Gould and his ilk, since Asians and Whites tend to perform better than blacks at taking IQ tests, such tests can’t possibly measure anything significant. Your psychologist friend reminds me of the behaviorist I quoted (and probably agrees with him). The histrionics of the Gould defenders on this forum remind me of a couple of historical anecdotes. In the 1930s, mathematicians knew in theory how to build a modern-like computer (Babbage designed one 100 years before) but couldn’t get the funding to build one until WW2. Turing showed theoretically that a computer can’t answer certain questions. His mathematical proof upset Marxist philosophers who, following Karl Marx, posulated that a Babbage-like computer should be able to solve _all_ problems. The Soviets actually jailed and executed several mathematicians for following Turing and Wiener and embracing the “bourgeois false science of cybernetics”. Following WW2, the Soviets’ official party line was that the Univac and other early computers were phoney (since they didn’t work according to Marxist theory) and there’s actually a person hiding inside the box typing out the answers, and throwing the switches than control the blinking lights. In the same timeframe, the Soviets executed several prominent geneticists for following Darwin/Mendel/Morgan’s teachings instead of Lamarck’s. (Have you ever heard of Trofim Lysenko? If not, do a web search on him. Gould is a Stalinist with about as much ethics/credibility/integrity as Lysenko.) Marxists also denied some aspects of Einstein’s relativity theory (and some still do) because it contradicted certain philosophical opinions expressed by Karl Marx and Frederick Engels. Aristotle postulated than heavier objects fall to the ground faster than lighter objects. Galileo got into trouble with the Catholic church, among other things, for trying to verify this assertion experimentally: he threw objects from a tower and measured the time it took them to reach the ground. (In case you don’t know, he found that the mass made no difference.) [Previous page](https://boards.straightdope.com/t/inherited-intelligence/5807.md?page=1) [Next page](https://boards.straightdope.com/t/inherited-intelligence/5807.md?page=3)