Why Smart People Are Actually Dumb

The human brain is a weird thing. When confronted with a new, uncertain situation, it virtually always abandons careful analysis and instead resorts to a host of mental shortcuts that almost always lead to the wrong answer. Turns out, the smarter you are, the more likely you are to make such mistakes.

A new study, published in the Journal of Personality and Social Psychology, suggests that you can be insanely intelligent and still fall foul when it comes simple problems because of deviations in judgment known as "cognitive bias".

To work all this out, a team of researchers form the University of Toronto gave 482 students a questionnaire of classic bias problems to complete. An example question runs along the lines of:

A bat and ball cost a dollar and 10 cents. The bat costs a dollar more than the ball. How much does the ball cost?

If you're rushing, you might blurt out that the ball costs 10 cents. It doesn't: it costs five. If you got it wrong, your brain made some shortcuts if thought made sense but abandoned maths along the way. (If you're sitting there incredulously assuming that anyone getting that wrong is a dumbass, you'll be interested to know that more than 50 per cent of students at Harvard, Princeton and M.I.T. give the incorrect answer.)

The researchers also measured a phenomenon called "anchoring bias", but what they were really interested in assessing was how the biases correlated with intelligence. So they interspersed tests with with cognitive measures, such as SAT and Need for Cognition Scale questions.

The results are unnerving. Firstly, awareness of bias in one's thinking doesn't help. As the researchers explain, "people who were aware of their own biases were not better able to overcome them". Dammit.

Turns out that intelligence makes things worse too. Writing in the Journal of Personality and Social Psychology, they explain that "more cognitively sophisticated participants showed larger bias blind spots". In fact, that finding is held across many different biases, and individuals who deliberated longer seemed to be even more susceptible to making mistakes. Double dammit.

So what's going on? Why are smart people seemingly so dumb some of the time? Sadly, nobody really knows. The best hypothesis yet suggests that it's tied up to the way we perceive ourselves and others. Basically, the way we process information, so some researchers suggest, makes it far easier for us to spot biases in other people than it is for us to notice ourselves making the exact same mistakes.

As a result, it's not clear whether there's anything that can be done about shaking off the problem. I'd suggest a drink to take the edge off your intelligence, but even then I can't guarantee that would make things any better. [Journal of Personality and Social Psychology via The New Yorker]

Image: Lasse Kristensen/Shutterstock


    British scientists?

    Smart and intelligent people have too much knowledge sometime and they know that 2*2 is not always 4. That's why hearing clop they might imagine zebra and make a mistake.

    BTW, those who answered 10 cents ARE DUMBASSES, despite educational establishments they are visiting.

      it describes that the ball and bat are $1.10 maybe the ball is a dollar and the bat is 10 cents wow.

        No. It says that the bat costs $1 more than the ball. Therefore the ball has to cost 5c and the bat has to cost $1.05

    While I admit that the study produced an intriguing result, it does raise some questions in my mind as to the applicability to the wider population and practical applications...

    Harvard, MIT, Princeton... all notably from the United States, which I would hardly call a paragon of mathematical education. I would definitely like to see a replication of this experiment in cross-cultural studies having a look at Chinese, Indian, African, and Europeans.

    There's also the notion that smart people might check their responses more often. Blurting out "10 cents" may be what they do more often, but do they realise that this is wrong more often than those with "less intelligence"? My initial thoughts were 10c, but I quickly checked that answer and found it added to $1.20, which means it was wrong so I change my answer accordingly.

      I'm more interested to know why the general public perceive intelligent individuals as unable to make simple and negligent mistakes. "We're only human" applies to all of us regardless.

      American Ivy League schools are actually the institutions of choice for the 'best and brightest' from all over the world, and MIT in particular has a VERY strong applied and theoretical maths background. Unfortunately, since the US doesn't really fund education publicly, the smart folks entering on merit are mixed in with a lot of less talented but more financially equipped students. It's the rich kids' tuition fees that keep the Ivy League going, and the scholarship kids keep the reputation high... But I digress - these schools will certainly contain an international selection of top students - but not exclusively.

      I suck at maths but I understood this... it is a bit of a trick question I guess.

    Simultaneous equations for the win :-)

    I read it as "a bat AND ball costs $1.10" and pictured one of those bat and ball packs you see at toy stores. So how much is the ball? $1.10, because you have to buy both. Anyone else think the same?

      just :)

    x + y = 110 cents
    x = y + 100 cents

    (y + 100) + y = 110

    2y = 10

    y = 5

    (bat) - (ball)
    105 - 5 = 100 cents => bat is a dollar more than the ball

    However, if you were to say the ball costs 10 cents, the problem is 100 + 10 = 110
    the difference between the cost of the bat and the ball is definitely less than 100 (a dollar). Hence the above :)

    So... I got it right. Does that mean I'm not smart?
    Suspicions confirmd.

    "makes it far easier for us to spot biases in other people than it is for us to notice ourselves making the exact same mistakes."

    A Jewish carpenter said something like this over 2000 years ago he was eventually executed by an authoritarian regime. Potentially dangerous claims to make if history is anything to go by ;)

      You believe that to be history?

        Actually Dr Doom, regardless of whether you believe Jesus is God or not, most historians treat the bible as a historical document and recognise its value as a source of historical information about the man Jesus. I had several lecturers at university (and friends who studied at other universities experienced the same thing) who supported the use of the bible as a historical source (and we all attended public, very secular universities). Whether you believe Jesus' divine claims is another matter entirely. Nomea made an interesting observation :P

    It's called inertia. Our brain analyses the problem, looks for existing circuits. If we have a circuit in our brain already, we'll use it, even if it is the wrong one. If we don't, we have to expend extra effort to generate the new circuit. It's a bit like caching really. Saves time and effort, at a cost to accuracy. but probably worth it over time

      BTW, it took me about 1 minute of thinking to get the answer. My excuse is that my brain needed to wire up new circuits!

        fizzzz :P

      That's not called inertia, nor is it what inertia is.

        ok, resistance, laziness, being 'smart' about expending energy. I'm not talking about hte scientific term

        Someone seems to be taking offence to opinions :)

          Duh!! That was for Flux... who seems to be on the offensive...

    Also, this kind of study probably only measures 'right' and 'wrong' answer. I would posit the more intelligent people would have a better 'wrong' answer, than less intelligent people whose wrong answer is probably 'more wrong'. Think this distinction is important. It's like a person being asked to estimate how many cars there are in Sydney. A less intelligent person might just grab a figure, say 1 million. Whereas a more intelligent person is more likekly to come up with a guesstimate that involved a bit more thought than that (like applying car usage rates by the population).

    I got it wrong, and I had to read Karthik's comment to understand why.
    I didn't consider the 'more' aspect, I stopped at 'the bat costs a dollar'.

    Okay, clearly I'm quite stupid...
    Karthik wrote
    x + y = 110 cents
    x = y + 100 cents - x is obviously 100c
    (y + 100) + y = 110 - y is obviously 10c
    2y = 10 - where the hell does 2y come from there is only one y in the equation and 2 x y would be 20?
    y = 5
    (bat) – (ball)
    105 – 5 = 100 cents => bat is a dollar more than the ball
    I'm not saying that the maths is wrong, but it dont make sense to me. X = 100, y = 10

      Pretty straightforward:

      x = bat
      y = ball

      if x + y = 110 cents ( bat + ball = 110 cents)
      then x = 100 + y ( bat = ball + 100 cents)

      to solve for y:
      (100 +y) + y = 110
      100 + 2y = 110
      2y = 10

      Ball costs 5c

      This comment has been deemed inappropriate and has been deleted.

        This comment has been deemed inappropriate and has been deleted.

        You're doing the simultaneous eqn wrong - if you want y to cancel out you have to ADD eqn 1 to eqn 2, thus 2*x = 210. You can't just futz the answer when you see it's wrong, and if you can't get this one you'll never get the hang of higher math (vector and matrix algebra springs to mind).

          This comment has been deemed inappropriate and has been deleted.

            Scrolling up shows you can grasp the substitution method, but it certainly doesn't excuse your methodology here. What fascinates is that you KNOW you got it wrong but rather than finding your error and editing your answer you just kept typing, stream of consciousness style... I simply presumed you had no idea where you went wrong.

            I'm thrilled you're employed, though.


    This is why you shouldn't use plain English in your math problems. Interpretation is a Bi*ch...

    My girlfriend got it by using maths, I got it wrong by guessing 1 dollar.

    Thinking about it now, if the bat cost 1 dollar and the ball 10 cents, the bat would cost 90 cents more than the ball and not a dollar.

    Dunno, why I am sucked into this :P

    Boy: Walks into a Sports store
    Store Manager: How can I help you?

    Boy: I would like to buy this ball
    SM: That will be 'y' cents

    Boy: I think, I will take this bat as well
    SM: "It costs a dollar more than the ball, thank you" *** IMPORTANT

    Boy: Walks home happily
    Mum: That's nice, so how much did you pay for the ball?
    Boy: 'y' cents
    Mum: And how much for the bat?
    Boy: A dollar more than 'y'
    Mum: That is?
    Boy: 100 cents + y cents for the bat

    ball = y cents
    bat = 100 + y cents
    total = 110 = bat + ball = (100 + y cents) + y cents
    110 = (100 + y cents) + y cents
    110 = 100 + 2 of y cents

    Woohoo = 5 cents

    Moral of the story:
    I should just have just bought the ball and a soft cone at MickyDs!!!

      If you just scroll up John just clarified it.

      Thank god you already employed because if you lose that job, you'll never get another one.

    Why are some smart people so dumb? It's called Multiple Intelligences.

    You may be fantastic at maths but suck at spelling, be fantastic with computers but suck at playing a muscial instrument.. it's a pretty good theory.

    I wanted to create a story board. Have a problem, don't read it :)

    if the ball cost 5 cents then the bat is now 1.05 a dollar and 5 cents more instead of being just a dollar more

      If the ball costs 5c and the bat costs $1.05, then the bat costs one dollar more than the ball.

      5c ball+$1 = $1.05 bat

      The bat does not cost a dollar extra (as you put it). It costs a dollar more than the ball.

    This comment was deemed inappropriate and has been moderated.

    This article doesn't really tell us much. It tells us all these conclusions but not how the researchers reached those conclusions - just that they did. Going by the sole example you've given - the ball/bat question and that smart people often give the incorrect answer - you could say it just means those people aren't very careful and put too much confidence in their own ability and don't double-check the answer before they give it.

    I have read explaination over and over and over, but I don't get it..
    Two items. A bat and BALL. there is no plural. two items, equalling $1.10
    The bat claims to be $1 more than the ball, leaving the only item left to be $.10
    It doesn't say that the bat cost $1.05c, they say A dollar more.

    I went down the shops and bought a loaf of bread and milk for $1.50
    the bread cost me $1 more than the milk.
    the milk cost $.50c.
    ^^^^^^^ is all i see in the bat and ball..

    someone please put this in elementary terms.. my villager mind doesn't get it.

    i just got it.. fml

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