Are Humans Getting Cleverer?

William Kremer, BBC News, March 1, 2015

It is not unusual for parents to comment that their children are brainier than they are. In doing so, they hide a boastful remark about their offspring behind a self-deprecating one about themselves. But a new study, published in the journal Intelligence, provides fresh evidence that in many cases this may actually be true.

The researchers–Peera Wongupparaj, Veena Kumari and Robin Morris at Kings College London–did not themselves ask anyone to sit an IQ test, but they analysed data from 405 previous studies. Altogether, they harvested IQ test data from more than 200,000 participants, captured over 64 years and from 48 countries.

Focusing on one part of the IQ test, the Raven’s Progressive Matrices, they found that on average intelligence has risen the equivalent of 20 IQ points since 1950. IQ tests are designed to ensure that the average result is always 100, so this is a significant jump.

The gains have not been evenly spread. IQ has generally increased more rapidly in developing countries, with the biggest leaps seen in China and India. Progress in the developed world has been checkered–the data seem to indicate steady increases in the US, for example, but a decline in the UK.

The new research is further confirmation of a trend that scientists have been aware of for some time. In 1982, James Flynn, a philosopher and psychologist based at the University of Otago in New Zealand, was looking through old American test manuals for IQ tests. He noticed that when tests were revised every 25 years or so, the test-setters would get a panel to sit both the old test and the new one.

“And I noticed in all the test manuals, in every instance, those who took the old test got a higher score than they did on the new test,” says Flynn. In other words, the tests were becoming harder.

This became known as the Flynn Effect, though Flynn stresses he was not the first to notice the pattern, and did not come up with the name.

But if the tests were getting harder, and the average score was steady at 100, people must have been getting better at them. It would seem they were getting more intelligent.

If Americans today took the tests from a century ago, Flynn says, they would have an extraordinarily high average IQ of 130. And if the Americans of 100 years ago took today’s tests, they would have an average IQ of 70–the recognised cut-off for people with intellectual disabilities. To put it another way, IQ has been rising at roughly three points per decade.

This is a puzzle not just for the US, but for all countries demonstrating the Flynn Effect. “Does it make sense,” Flynn wrote in one paper, “to assume that at one time almost 40% of Dutch men lacked the capacity to understand soccer, their most favoured national sport?”

So what is going on? “There are lots of theories, none of which is particularly proven,” says Robin Morris.

One possible explanation has to do with changes in education.

In most of the developed world, more people are now in school for longer, and teaching methods have evolved, moving away from the simple memorising of names, dates and facts. It seems like a reasonable assumption that education is training people to think better.

But in fact, the evidence is mixed. There has been no clear correlation between the rising IQ scores and US school performance–in SAT tests, for example.

But school prepares children for sitting IQ tests in other ways–what the psychologist Arthur Jensen called “test wiseness”. Over time, students become used to the pressure of tests and they pick up examination-room tactics that improve their performance.

A vivid demonstration of this emerges from a study of raw IQ data from Estonia. When psychologists Olev and Aasa Must laid examination papers from the Estonian National Intelligence Test from the 1930s alongside papers from 2006, they found an increase in correct answers–and also incorrect ones. The more recent students knew that they would not be penalised for guessing and getting something wrong.

James Flynn believes test wiseness may have been a factor in IQ gains in the US in the first half of the 20th Century. However, since then the amount of IQ testing taking place has waned–and IQ increases have remained steady.

Flynn puts this continued progress down to profound shifts in society as well as education over the last century, which have led people to think in a more abstract, scientific way–the kind of intelligence measured by IQ tests.

He cites the work of Russian neuroscientist Alexander Luria, who studied indigenous people in the Soviet Union. “He found that they were very pragmatic and concrete in their thinking,” says Flynn, “and they weren’t capable of using logical abstractions or taking hypotheticals seriously.” Luria put the following problem to the head man of one tribe in Siberia: Where there’s always snow, the bears are white; there’s always snow at the North Pole–what colour are the bears there?

The head man replied that he had never seen bears that were any colour other than brown, but if a wise or truthful man came from the North Pole and told him that bears there were white, he might believe him. The scientific methods of hypothesising, classifying and making logical deductions were alien to him.

“Now virtually all formal schooling, when you get past the sixth grade into high school and college, means that you take hypotheses seriously,” says Flynn. “This is what science is all about. And you’re using logic on abstract categories.”

And this kind of thinking doesn’t only occur in school.

As Flynn pointed out in his Ted Talk on the Flynn Effect, in 1900 only 3% of Americans performed “cognitively demanding” jobs–now the figure is 35%, and the work itself is far more intellectually demanding than it was a century ago. Families are also smaller, so children are exposed to more adult conversation at the dinner table than in the past. “Hothouse parenting”–pushing your kids to achieve goals from an early age–may also be a factor. And when it comes to older people, a lower disease burden may have an effect on their performance in tests.

Such effects have diminishing returns after countries become fully industrialised, Flynn says, which may explain why in some North European countries, including France and Scandinavia, IQs have flatlined or diminished slightly. He admits that the pattern in Europe is a little baffling, but he has an idea why IQ scores continue to rise in the US. “I think America is a society where economic and environmental differences are much greater than they are in Scandinavia. And for example black Americans have terrible schools, and they have had terrible conditions to live under.”

A few other possible causes for the Flynn Effect have been put forward, some of them very intriguing.

One, proposed by Arthur Jensen but yet to be investigated, points to the spread of electric lighting. The thought is that light from bulbs, TV screens and the like may have contributed to cognitive development in a similar way that artificial light stimulates growth in chickens.

Then there is the theory that today’s world is more visual than the world of 100 years ago. The Raven’s Progressive Matrices–the subject of the recent international study into the Flynn Effect by Wongupparaj, Kumari and Morris–requires people to pick out patterns from an array of stripes and squiggles. This particular test has seen the biggest IQ increases of all. Perhaps television, video games, advertisements and the proliferation of symbols in the workplace have made it easier for us to decode pictorial cues and identify patterns?

There is also a debate surrounding nutrition. In a 2008 article in Intelligence, Richard Lynn notes that measures of infants’ mental development increased in the UK and US at rates correlated to the increasing IQs of slightly older children. It’s difficult to see how Flynn’s theories are enough to explain this. “Are infants thinking more scientifically today?” he asks rhetorically.

Lynn argues that pre-natal nutrition is a determinant of birth weight, which is in turn correlated to higher IQs. A shortage of one particular nutrient–iodine–is known to stunt intellectual development in growing children. A 2005 paper examining iodine deficiency in China found that children’s IQ scores were higher in areas where there was no iodine deficiency, and it increased after a programme of supplements started.

So explanations of the Flynn Effect abound–but what precisely does it signify? Do these steadily improving results indicate that the IQ test is not, after all, measuring intelligence? Or are people really cleverer than their forefathers?

“I don’t think smarter has anything to do with it,” says Flynn.

“Today we have a wider range of cognitive problems we can solve than people in 1900. That’s only because society asks us to solve a wider range of cognitive problems. People in 1900 had minds that were perfectly adequate for remembering first cousins once removed, they were perfectly adequate for ploughing a farm, they were perfectly adequate for making change in a store. No-one asked them to do tertiary education.

“It’s like a weightlifter and swimmer. They may have the same muscles when they were fertilised in the womb, but they would have different muscles at autopsy, wouldn’t they? So today at autopsy, certain portions of our brain, for example those which use logic and abstraction, would have been exercised more and look differently. Other portions of the brain would have shrivelled a bit.”

It may be, then, that certain abilities–problem-solving or reasoning ability, say–have improved but a general, underlying cognitive ability has not changed. This general ability is fundamental to the way many scientists view intelligence. Although little is actually known about it, there is supposed to be a general, hereditary quality that makes an individual who is good at giving fine speeches more likely to be good at Sudoku too. The problem is that this general cognitive ability is exactly what IQ tests are supposed to measure–in fact, of all the components of the IQ test, the Ravens test was supposed to be the truest measure of it. If people aren’t becoming fundamentally more intelligent, IQ tests aren’t doing what they’re supposed to do.

But Robin Morris is prepared to entertain the possibility that there may, over time, have been a real increase in general cognitive ability.

“It seems to me that it’s reasonable to think that intellectual functioning could increase over time in more developed societies,” says Robin Morris.

But do we actually notice in our midst a higher proportion of geniuses than there were in earlier generations?

“That’s the baffling aspect,” Morris admits. “How could it go up so much but there aren’t all these very very smart people floating around? And that is a bit of a puzzle. But then, people have started to say, ‘Maybe there are more bright people floating around and they’re kind of hidden away because of the way science has become very specialist. They’re working in their own particular field and they’re doing amazing things–they’re acting as geniuses–but they’re not necessarily identified as such.'”

It’s an odd thought. There are more and more geniuses out there, if this theory is correct–but many of them are unrecognised.

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  • JackKrak

    More toys than years ago? More access to everything, opportunities that past generations didn’t have? More amenities, comforts, conveniences and cures? Absolutely.

    Smarter? Not a chance.

    • Marilyn Rosen

      My son is only a year and when he gets access to phone or computer, he plays around with it and figures some of it out. I’m careful about him getting to my phone but it’s amazing what they do.

      • ghettovalley

        Slightly related, there are videos on YouTube of babies attempting to swipe magazines as you would a smartphone or tablet. Some of them get very frustrated with the magazine since obviously it doesn’t work. Personally, I want my children to know the joy of owning and reading actual books. I think that many in this country let their children use the internet completely unfiltered and unsupervised from an early age and it will almost certainly have an extremely detrimental effect on the future of our country and the moral character of our descendants.

        • Marilyn

          I agree with you on that. I have a ton of books and magazines and my son loves them. I have a friend who suggested I use a app for games while on we go on vacation (my husband won’t fly til they get rid of TSA) but I figure we play games in the car like counting the red cars we see and stuff like that

  • JohnEngelman

    There has been no clear correlation between the rising IQ scores and US school performance–in SAT tests, for example.

    – William Kremer, BBC News, March 1, 2015

    Since the school year of 1986-87 white scores on the SAT have improved somewhat. Black scores, which were always much lower than white scores, have hardly improved at all. In order to benefit from an improved environment one must have the talent to benefit.

    • WilmotRobertson

      Yup. The analogy I always use to understand the effect the environment will have on a particular individual is that of condensation nuclei. For a snowflake to form, it must have a nuclei on which to crystallize like dust or some other particle. Nature is the nuclei, nurture is the crystal that forms on it. Without the nuclei there will be no crystal.

      • awb

        You can educate intelligence , you can not create it.

        • WilmotRobertson

          Well put.

  • Tarczan

    It’s hard to imagine that an organ that has slowly evolved over millions of years will suddenly (in 100 years) exhibit a change as drastic as the change 20 IQ points indicates.

    • Usually Much Calmer

      It all depends on the sort. Imagine a population of frogs with cold tolerance Gaussian distributed around 15 degrees with standard deviation of 10 degrees.

      The day after a 5 degree night, the population of frogs is suddenly vastly different. So the mean is vastly different.

    • WhiteGuyInJapan

      Not so sure about that. Microevolution can take place rather quickly (in evolutionary terms). Cochran and Harpending wrote The 10,000 Year Explosion documenting the rapid evolution of our brains and our behavior as we moved from hunter/gatherers to farmers and city-dwellers. The Industrial Revolution is even more recent and has clearly shaped our lives and thinking in previously unimaginable ways.

      As Wade put it: “human evolution has been recent, copious and regional”.

  • LHathaway

    “Perhaps television, video games, advertisements and the proliferation of symbols in the workplace have made it easier for us to decode pictorial cues and identify patterns”?

    This man stole my idea . . . !

  • superlloyd

    Despite the Flynn effect, the racial gap between Whites and blacks is as consistent as ever. I standard deviation or a bit more for over a century despite numerous, fruitless attempts to eradicate it.

  • IstvanIN

    Maybe all these computer-type products that children are surrounded by are speeding up there development?

  • dd121

    General intelligence is in the genes. All the other effects are smoke and mirrors.

  • USofAntiWhite

    Just about everything in this article is backwards, the opposite of the truth. With the exception of the part about IQs in The UK dropping; Pakistani and South Asian immigration will have that outcome.

    • superlloyd

      Don’t forget the near retarded negroes who number some 2 million alone.

    • Leelywhite

      This article proves we’re getting stupider. Recently the “Spectator” magazine reproduced an entrance exam for grammar schools in Britain from a hundred years ago. Today university students would battle to pass it. How many young people today know how to parse a sentence?
      I’m reminded of the IQ test in “Idiocracy”: if one basket has three marbles, another has 5 marbles and yet another seven marbles, how many baskets have you got?

  • RacialRay

    There are such vast differences in cognitive ability between the various demographics that make up the aggregate known as “Americans” that conclusions such as are drawn here become meaningless. How can you compare “Americans” of 1950, before the modern immigrant wave reached our shore with “Americans” of today? Break it out by race and national origin and tell us again if “we” are really getting any smarter or not.

    At least separate the apples and oranges from the coconuts.

  • TruthBeTold

    IQ has generally increased more rapidly in developing countries, with the biggest leaps seen in China and India.

    Hasn’t it been reported that the Chinese are known to cheat on tests?

    Could the gains in Chinese IQ plausibly attributed to some degree of cheating?

    • Sick of it

      Selective sampling is the biggest problem over there.

      • WilmotRobertson

        I think that makes most sense.

    • Ultimate187

      Unlikely. Their scores are consistent with their behavior and high overall functioning in real life.

    • 李冠毅

      Perhaps. Or more likely, it was due to samples unrepresentative of the national populace. I’ve read about a case in which the national IQ score of China was rejected as false because the test takers were all from Shanghai, an elite Chinese city. But then again, China has over 1 billion people. Testing even a small percentage of that is going to be costly and time consuming.

      • John Smith

        No way I can believe 158, especially averaged amongst 1.2 billion.

        • WhiteGuyInJapan

          158? No way. The mean IQ for the East Asian nations ranges between 105-108. 158 is well into genius level.

          • John Smith

            Exactly – we know that isn’t true by meeting Chinese people in places other than academia (and even there it beggars credibility), like the local Chinese Buffet restaurant.

          • WhiteGuyInJapan

            I travel a lot around Asia and there are always swarms of Chinese tourists around. Crowding up hotel lobbies and climbing up 11th century Khmer stupas. Shockingly rude people.

            Having said that,manners is highly dependant on culture and may not have much to do with intelligence. One can be smart and rude at the same time. Likewise, I have met people who are not particularly bright but who are well-mannered.

        • Sick of it

          They would not have lost to the British Empire if that were true.

          • 李冠毅

            Actually, history is more complicated than that. Try reading up on the Mongol invasion of China and Europe.

    • Oil Can Harry

      Probably the main reason for the rise in IQs in the developing world is environmental: less malnutrition and parasites.

  • TruthBeTold

    IF there are any increases in IQ I attribute them to better nutrition, greater amounts of intellectual stimulation in the general environment and an increasing comfort and familiarity with test taking.

    I do believe you can raise an IQ score by a few points simply by taking tests and learning how to take tests better.

    However you can’t take someone with an average IQ and make him a genius.

    • ShermanTMcCoy

      But, but, but, that’s what I see in all the Hollywood movies!

  • blah1130am

    I think it’s motivation to do well on the tests. People ascribe more meaning to IQ now than they did before and try harder when they’re given the test.

  • Sick of it

    “Flynn puts this continued progress down to profound shifts in society as
    well as education over the last century, which have led people to think
    in a more abstract, scientific way–the kind of intelligence measured by
    IQ tests.”

    Flynn, apparently, is too stupid to see the actual world around him.

  • Ultimate187

    Better nutrition, better healthcare, better education (maybe) all exert a positive eugenic effect on society. Our increasingly knowledge-based world will also select for a more intelligent populace. Over time offspring may indeed be naturally smarter than their parents.

    • Sick of it

      Better healthcare/prenatal care for all means we will continue to be swamped by the sheer number of low IQ people brought into the world. We have many jobs today which require an actual brain…that are being outsourced to morons in India. Kids today are more likely to breed with dumber people because it makes them feel good.

  • WR_the_realist

    I’m not really sure what to make of the Flynn effect, but one thing is obvious — if we’re 30 IQ points smarter than our great grandparents then our great grandparents must have been gibbering idiots. But they weren’t. So something is wrong here.

    Luria put the following problem to the head man of one tribe in
    Siberia: Where there’s always snow, the bears are white; there’s always
    snow at the North Pole–what colour are the bears there?

    The head man replied that he had never seen bears that were any
    colour other than brown, but if a wise or truthful man came from the
    North Pole and told him that bears there were white, he might believe

    That strikes me as a very sensible answer.

    • libertarian1234

      “So something is wrong here.”

      There certainly is. Flynn is a crusty old bigot whose claims are nonsense.

  • libertarian1234

    “…… they found that on average intelligence has risen the equivalent of 20 IQ points since 1950.”

    I don’t believe that even for a minute.

    In fact going back into the 19th century looking at tests taken by 8th graders reveal they were as advanced and knowledgeable as high school seniors are today, and that wouldn’t be possible if their average I.Q.’s were lower.

    There are other yard sticks that make that claim bogus, also.

  • Reynardine

    Flynn Effect is a politically correct way of trying to express differences that would otherwise be difficult to explain.

  • ghettovalley

    Are humans getting cleverer? Maybe certain varieties of humans. Others seem to be moving in the opposite direction. What is human? Where do we draw the line between man and beast? At what point did hominids become men? At what point do we classify a regressed man as an animal? Sometimes I wonder if blacks are a little more different than we’re led to believe.

    • ElComadreja

      I don’t wonder at all.

  • PostBunnie

    Better nutrition also has my primary vote. Then there might be more familiarity with various problem solving techniques. Kids tend to do things faster with more “gut” feelings, especially with all the Lightning reflex video games. Doing the tests faster adds points to some tests right? Or some of the questions become too common. (I know I see pattern and logic puzzles posted on Facebook. And some have been similar in form to IQ test questions)

    I believe g is mostly hereditary, but I’m still planning on doing all the standard “boosts” for my babies. (Extended Breastfeeding, reading together, variety of external stimuli) Maybe with all the “super baby” pressure does work.

    • Sick of it

      Once they are old enough to eat it, feed them meat. Actual meat which came from an actual animal. This sort of thing should be obvious, but there are so many weird vegan types today who don’t realize they are destroying their children.

  • John Smith

    The results of the 2008 and 2012 elections say otherwise.

  • Alden

    It’s more clever, not cleverer.

  • Bill Moore


    My mother, born in 1907, and only went to third grade, when she was in her 80s, could multiply a three digit number by a two digit number in her head in less than a couple of seconds (e.g., 23×367). And she could do it while washing dishes.

    She lived on a farm most of her life, and had 10 children.

    I think the folks in the USA are getting less intelligent (maybe not less intelligent, maybe less educated). Try discussing geography, history, or math with any high school student. You will be appalled.

    I went into a store and made a hundred copies. The copies were five cents each, with a six percent sales tax. The computer was down. The young woman who was the cashier was told by the owner (who was working on the computer) to make a note of each sale, and they could enter each sale into the computer system after he got it working.

    When I stepped up to cashier, she tried to compute the cost. She figured it out on a note pad and came up with $15.75. I told her that was not correct. She tried several times (each computation took a couple of minutes), was wrong every time, and a line formed behind me, mostly older folks.

    The sixty and seventy year old people in the line behind me started calling out “five dollars and thirty cents”. Finally, the owner, looking up from the computer, told her that the correct amount was five dollars and thirty cents.

    Bill Moore

  • Garrett Brown

    How is the Flynn effect still happening with the amount of dygenic immigration happening?

  • WhiteGuyInJapan

    Yes! Even with increases in environmental IQ, genetic IQ will be constant. Imagine every American gets an extra 5 points on their IQ. The Asian>white>black scale would still stand. Even with mean IQ scores of 110/105/90, the racial demographics at Google would not change much.

  • EpiphanyStrachan

    People are becoming more intelligent but not smarter- there is a big difference.

  • Augustus3709

    Fascinating Topic. Some of it is hard to imagine though. They’re saying the average White person of 100 years ago was the same intelligence of the average Black person today. I find that hard to believe. But then again, could it be true? Whites were significantly more religious, and also capable of group-think and mass mob activity.

    Do they take into consideration that French and Scandinavian IQs are dropping due to immigration? Or is it actually due to industrialization. What would that mean? Access to machinery and automation causes the brain to diminish? Could be plausible.

    Moving forward we should try to maximize both aspects of thought; the abstract and the practical. Standard schooling should include things like homemaking and handiwork.