How We Know That Humans Are Getting Smarter [Excerpt]

In this excerpt from his new book, James R. Flynn explains how he came to understand how our minds have gained in cognitive skills during the 20th century















Share on Tumblr

Some years ago, acting as an archaeologist, I amassed a large body of data showing that IQ tests had gotten easier. Over the twentieth century, the average person was getting many more items correct on tests like Raven's and Similarities. The response of intelligence- or g-metricians was dual [Editor's note: See here for an exploration of the "general intelligence" factor g]. First, they distinguished IQ tests as measuring instruments from the trait being measured, that is, from intelligence (or g if you will). Second, they noted that in the absence of an absolute scale of measurement, the mere fact that the tests had gotten easier told us nothing about whether the trait was being enhanced. IQ tests were only relative scales of measurement ranking the members of a group in terms of items they found easy to items they found difficult. A radical shift in the ease/difficulty of items meant all bets were off. At this point, the g-metrician decides that he cannot do his job of measurement and begins to look for an absolute measure that would allow him to do so (perhaps reaction times or inspection times).

However, as a cognitive historian, this was where I began to get excited. Why had the items gotten so much easier over time? Where was the alteration in our mental weaponry that was analogous to the transition from the rifle to the machine gun? This meant returning to the role of archaeologist and finding battlefields of the mind that distinguished 1900 from the year 2000. I found evidence of a profound shift from an exclusively utilitarian attitude to concrete reality toward a new attitude. Increasingly, people felt it was important to classify concrete reality (in terms the more abstract the better); and to take the hypothetical seriously (which freed logic to deal with not only imagined situations but also symbols that had no concrete referents).

It was the initial artifacts that caused all the trouble. Because they were performances on IQ tests, and IQ tests are instruments of measurement, the roles of the cognitive historian and the g-metrician were confused. Finding the causes and developing the implications of a shift in habits of mind over time is simply not equivalent to a task of measurement, even the measurement of intelligence. Now all should see that different concepts dominate two spheres: society's demands—whose evolution from one generation to the next dominates the realm of cognitive history; and g—which measures individual differences in cognitive ability. And just as the g-metrician should not undervalue the non-measurement task of the historian, so the historian does nothing to devalue the measurement of which individuals are most likely to learn fastest and best when compared to one another.

I have used an analogy to break the steel chain of ideas that circumscribed our ability to see the light IQ gains shed on cognitive history. I hope it will convince psychometricans that my interpretation of the significance of IQ gains over time is not adversarial. No one is disputing their right to use whatever constructs are best to do their job: measuring cognitive skill differences between people.

But an analogy that clarifies one thing can introduce a new confusion. The reciprocal causation between developing new weapons and the physique of marksmen is a shadow of the interaction between developing new habits of mind and the brain.

The new weapons were a technological development of something outside our selves that had minimal impact on biology. Perhaps our trigger fingers got slightly different exercise when we fired a machine gun rather than a musket. But the evolution from preoccupation with the concrete and the literal to the abstract and hypothetical was a profound change within our minds that involved new problem-solving activities.



13 Comments

Add Comment
View
  1. 1. TTLG 11:25 AM 9/28/12

    Interesting topic, but this excerpt was not enlightening, nor give me any confidence that this book will enlighten me on it. So I am going to pass on this one.

    Reply | Report Abuse | Link to this
  2. 2. schopenhauer1962 11:33 AM 9/28/12

    I read a lot of scientific articles, SA, Science books and the works of Immanuel Kant, mathematical proofs but this article is absolute gibberish to me.
    If people are getting smarter, why is it that young people entering the university are not really getting smarter ? Some of them lack the most basic skills, they know their way arounf the internet, "smart"phones, tablet pc's, etc ... but they lack the skills people had in the eighties. Standards are lowered in high schools to let a certain amount of students pass. They know every aspect of a certain video game, but do not ask them to solve a simple mathematical equation, ask them basic language skills ... And what is IQ really ? People train nowadays for a lot of tests, what is the validity of such tests ? What's the validity of a brain scan ? Do we really know the relation between blood flow/concentration and the activity in certain parts and what does that mean ? What are we comparing ? I know it's all hypothesis ...

    Reply | Report Abuse | Link to this
  3. 3. learningengineer 12:40 PM 9/28/12

    I guess if I had to sum up the article it would be this, "It's the culture stupid." Our culture worships technology and people who can quickly adapt to it. Our culture does not worship the math or communications skills required to build the technology we worship. IQ scores bare this out. It would seem that this could be used to point out the ineffectiveness of schooling in increasing intelligence.

    Reply | Report Abuse | Link to this
  4. 4. jtdwyer 03:02 PM 9/28/12

    I generally agree with the preceding commentators.

    I certainly haven't made a study of this subject, but several questions come to mind when comparing IQ test results over the past ~100 years. Of course, at the turn of the 20th century may people lived in rural communities who were not likely to receive much education. As I understand, even urban children were required to work at an early age. Nowadays, by comparison, while many may not be interested in education, most receive at least a modist amount of schooling. Moreover, since the past 50 years young children have spent much of their time watching TV programs and more recently playing video games. While these activities might not seem to be beneficial to IQ test scores, I think they contribute more than did manual child labor.

    Secondly, as I understand, IQ test scores are evaluated not for the general population, but for the population of those tested. Who takes IQ tests? I don't really know, but any measured change in IQ test scores over time reflects not on the general population but on the select population that takes IQ tests. Have the reasons people (are required to) take IQ tests changed over the past ~100 years? Again, I don't know, but I strongly suspect that they have, and the characteristics of the subpopulations taking IQ tests have changed significantly.

    Reply | Report Abuse | Link to this
  5. 5. Unksoldr 03:55 PM 9/28/12

    I see no evidence that mankind as a species is getting 'smarter' looking around at the world it would appear we're getting 'dumber'.

    Reply | Report Abuse | Link to this
  6. 6. jh443 07:39 PM 9/28/12

    I have recently returned to college after a 30+ year absence. If my observations are any indication, people may or may not be getting smarter, but they are certainly educated with less success than when I was young. Kids are entering college with reading / math skills that don't measure up to what our generation had upon graduating grade school! I'm beginning to wonder if it really is the FCAT (Google it) that's the problem, or the current generation's inability to perform at the required level.

    Reply | Report Abuse | Link to this
  7. 7. jtdwyer in reply to jh443 08:04 PM 9/28/12

    Valid point. However, I suspect this book is analyzing 'proper' IQ tests, excluding any results from achievement tests. The article states:
    "Over the twentieth century, the average person was getting many more items correct on tests like Raven's and Similarities."

    http://en.wikipedia.org/wiki/IQ_tests#Modern_tests
    states: "Well-known modern IQ tests include Raven's Progressive Matrices, Wechsler Adult Intelligence Scale, Wechsler Intelligence Scale for Children, Stanford-Binet, Woodcock-Johnson Tests of Cognitive Abilities, and Kaufman Assessment Battery for Children."

    It goes on to say that "The correlation between IQ test results and achievement test results is about 0.7." Also see:
    http://en.wikipedia.org/wiki/Achievement_test

    While achievement tests are often given to entire student populations to test specific skills taught in schools, I don't think that very many people take the more generalized IQ tests - which is I think the basis for the author's study and my earlier comment about possible changes in the selection criteria for sample populations taking IQ tests over time...

    Reply | Report Abuse | Link to this
  8. 8. CliffClark 10:39 PM 9/29/12

    Who is smarter? Everyone? Or just a small proportion of people? Given that we now know each brain "wires itself" in response to input and brains are plastic, what would this mean even if true? If each brain is indivually adaptive/adapted, the intelligence measured must be a consequence of the environment the developing brain finds itself in. How many people in the world take intelligence tests, and what proportion of the world population is therefore captured. What about the malnourished 1 - 1.5 billion people who, it is said, will never even come close to their physical or intellectual potential? What about the growing numbers of people who suffer from fetal alcohol syndrome? From autism? From other conditions that may affect brain development and intellectual achievement, some of which may results from increasing pollution or toxins in the environment of industrialized nations? What about the failure of educational systems in many developed countries to teach metacognition or critical thinking skills with the result that, whatever trend there is to improved marks on intelligence tests, many people remain slaves to their cognitive biases? The writer of the fragment placed before us for our consumption seems to either ignore many of these issues or, worse, not be aware of them.

    Reply | Report Abuse | Link to this
  9. 9. luhng 03:35 AM 9/30/12

    i do not believe for one minute that a bullet i
    hitting a target gives an accurate measure of one's intelligent factor. This is called hand eye coordination. If one can play a video game accurately (hand eye coordination) then the individual should be put in on the firing range. Intelligence is acquired through repetition and study along with self hypnosis which provides a path to the subconscious through the conscious. We as humans all have the ability to understand and gain knowledge. We all have the ability to use more than the said 10% brain power. yet most choose not to. While the few of us choose more.☺

    Reply | Report Abuse | Link to this
  10. 10. okburt75 06:12 AM 9/30/12

    My understanding of IQ tests is that 100 is taken as the mean result. Thus if everyone taking the test is super smart the mean would still be 100, the same if all taking the test were not so smart. Comparing tests would appear to be apples vs oranges. As pointed out in the above comments, it doesn't appear that our young people are super smart. More likely they are just better at playing games.

    Reply | Report Abuse | Link to this
  11. 11. Crasher 05:58 PM 10/1/12

    I don't tink we are becoming smarter but that the expression of 'intellengence' may be changing to reflect changes in the world and how we need to interact with it. People may now handle the IQ tests better but is this coming at a cost of other 'intelligence' related functions. As an example we seem to be losing some old fashioned basic abilities, eg the ability to understand and do basic maintenance on a car, or some other modern devices that we use everyday. This may be from my own personal experience but I have heard many people remark about the same. Perhaps we are absorbing a lot of higher learning at the cost of the basics.
    Just a thought....

    Reply | Report Abuse | Link to this
  12. 12. hastigo 02:54 PM 10/5/12

    To the editors...
    Sort of unfair to the author in leading off with these relatively uninformed & very 'spot' opinions.

    He begins with an analogy to make as clear as he can & beforehand the complexities of mensuration of this capacity (these cognitive capacities).
    And then goes to a thesis which he does well...however little <b>I</b> may understand the tricks of the playing field which is home to these arguments.
    [I am simply NOT a neuro-, cognitive scientist and have little personal business or acquaintance ON that field.]

    I do think he might have 'dumbed down' his brief but believe he got the job done.

    Simple version..as our brains-in-evolution are presented with (ever?)more complex cognitive issues they physically
    - all the pertinent 'plug-ins' and 'cabling' [DTI stuff, white matter connectivity] - evolve to deal with the problem(s) presented.

    When you need to hunt your (our) brain(s) will evolve to do this ever better, your descendants will persist better.
    When the problem is a four-way stop or a complex traffic robot or any such more abstract issue:
    Say, getting an electrical power switch rewired to get your refrigerator up and cooling again...or worse, a
    computerized control issue to accomplish the same thing..or whatever...
    That 10 pounds of brain will get right to work anatomically/physiologically & later evolutionarily
    reworking its innards to deal with these survival challenges.
    [By the way: None of this begins to address any real-time epigenesis which may be operative.]

    And as we individually & culturally engage in our persistently ever more complex machinations
    that lovely & ever-malleable organ goes right along in ordering itself to deal with ANY problems as they present.

    The author's was a very good presentation.

    jamesT.

    Reply | Report Abuse | Link to this
  13. 13. hastigo 02:57 PM 10/5/12

    [may be twice submitted..page unresponsive]
    To the editors...
    Sort of unfair to the author in leading off with these relatively uninformed & very 'spot' opinions.

    He begins with an analogy to make as clear as he can & beforehand the complexities of mensuration of this capacity (these cognitive capacities).
    And then goes to a thesis which he does well...however little <b>I</b> may understand the tricks of the playing field which is home to these arguments.
    I am simply NOT a neuro-, cognitive scientist and have little personal business or acquaintance ON that field.

    I do think he might have 'dumbed down' his brief but believe he got the job done.

    Simple version..as our brains-in-evolution are presented with (ever?)more complex cognitive issues they physically
    - all the pertinent 'plug-ins' and 'cabling' [DTI stuff, white matter connectivity] - evolve to deal with the problem(s) presented.

    When you need to hunt your (our) brain(s) will evolve to do this ever better, your descendants will persist better.
    When the problem is a four-way stop or a complex traffic robot or any such more abstract issue:
    Say, getting an electrical power switch rewired to get your refrigerator up and cooling again...or worse, a
    computerized control issue to accomplish the same thing..or whatever...
    That 10 pounds of brain will get right to work anatomically/physiologically & later evolutionarily
    reworking its innards to deal with these survival challenges.
    [By the way: None of this begins to address any real-time epigenesis which may be operative.]

    And as we individually & culturally engage in our persistently ever more complex machinations
    that lovely & ever-malleable organ goes right along in ordering itself to deal with ANY problems as they present.

    The author's was a very good presentation.

    jamesT.

    Reply | Report Abuse | Link to this
Leave this field empty

Add a Comment

You must sign in or register as a ScientificAmerican.com member to submit a comment.
Click one of the buttons below to register using an existing Social Account.

More from Scientific American

Follow Us:

See what we're tweeting about

Scientific American MIND

More »

Free Newsletters


Get the best from Scientific American in your inbox

Solve Innovation Challenges

Powered By: Innocentive

  SA Digital
  SA Digital

Science Jobs of the Week

Email this Article

How We Know That Humans Are Getting Smarter [Excerpt]

X
Scientific American Mind

Subscribe Today

Save 66% off the cover price and get a free gift!

Learn More >>

X

Please Log In

Forgot: Password

X

Account Linking

Welcome, . Do you have an existing ScientificAmerican.com account?

Yes, please link my existing account with for quick, secure access.



Forgot Password?

No, I would like to create a new account with my profile information.

Create Account
X

Report Abuse

Are you sure?

X

Institutional Access

It has been identified that the institution you are trying to access this article from has institutional site license access to Scientific American on nature.com. To access this article in its entirety through site license access, click below.

Site license access
X

Error

X

Share this Article

X