# Why do some people have difficulty grasping exponential growth? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [November 24, 2011, 5:37pm UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987 "2011-11-24T17:37:24Z")\ **Posts on this page:** 12\ **Page:** 2
**Author:** ![John\_DiFool](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_difool/32/19543_2.png) [@John\_DiFool](https://boards.straightdope.com/u/John_DiFool)\ **Post date:** [November 25, 2011, 12:36am UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/21 "2011-11-25T00:36:32Z")
Here’s another one: if you could fold it 50 times over, how wide and long is the stack? Assume the original is 16 x 16 inches (and thus a square, so the final fold should create a square-I think). My estimate is a few microns wide. 😃 ---
**Author:** ![don\_t\_ask](https://avatars.discourse-cdn.com/v4/letter/d/e68b1a/32.png) [@don\_t\_ask](https://boards.straightdope.com/u/don_t_ask)\ **Post date:** [November 25, 2011, 2:29am UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/22 "2011-11-25T02:29:40Z")
I assume the OP is familiar with [the greatest shortcoming of the human race is our inability to understand the exponential function](http://www.youtube.com/watch?v=F-QA2rkpBSY)? ---
**Author:** ![Galileo](https://avatars.discourse-cdn.com/v4/letter/g/85e7bf/32.png) [@Galileo](https://boards.straightdope.com/u/Galileo)\ **Post date:** [November 25, 2011, 3:36am UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/23 "2011-11-25T03:36:49Z")
Yup. I thought of including a link to [Al Bartlett](http://www.AlBartlett.org/) in the OP but I decided against it. There’s also Kurzweil’s [Law of Accelerating Returns](http://www.kurzweilai.net/the-law-of-accelerating-returns): > [@](#): > > An analysis of the history of technology shows that technological change is exponential, contrary to the common-sense “intuitive linear” view. > … > You will get $40 trillion just by reading this essay and understanding what it says. ---
**Author:** ![BellRungBookShut-CandleSnuffed](https://avatars.discourse-cdn.com/v4/letter/b/bcef8e/32.png) [@BellRungBookShut-CandleSnuffed](https://boards.straightdope.com/u/BellRungBookShut-CandleSnuffed)\ **Post date:** [November 25, 2011, 3:59am UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/24 "2011-11-25T03:59:45Z")
> [@jz78817](#): > > it’s like that stupid shit that went around (and leaked out of) facebook a while back, the “1x1x1x1x1x1x1x1x1x0=?” thing. I absentmindedly nerfed it the first time _because I wasn’t arsed to look at it carefully and remember order of operations._ It’s one thing to not look at a stupid brain teaser thing carefully. It’s another to have to “remember” the order of operations. I agree that people don’t really remember factoring and such without kicking their brains into gear or going to look it up, but order of operations? PEMDAS? How do people who can’t remember that do anything with math? I can even see how parentheses and exponents might be hard to remember. But if you (the general you) can’t remember that multiplication/division comes before addition/subtraction, I’d say your schools failed you. It’s really one of the most basic concepts, on par with tipping at restaurants or dividing up portions or deciding what people need to pay on a receipt. And this is from someone who hated math and became an English major. Also, you apparently “nerfed” that equation above as well, because the “gotcha” equation was 1+1+1+1+1x0. The one you posted equals 0. Also, I don’t think [nerfed](http://www.urbandictionary.com/define.php?term=nerfed) means what you think it means. ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [November 25, 2011, 5:49am UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/25 "2011-11-25T05:49:21Z")
anything else you want to tell me I’m wrong about, **BellRungBookShut-CandleSnuffed**? ---
**Author:** ![Rachellelogram](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rachellelogram/32/8689_2.png) [@Rachellelogram](https://boards.straightdope.com/u/Rachellelogram)\ **Post date:** [November 25, 2011, 5:59am UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/26 "2011-11-25T05:59:01Z")
Why do some people have difficulty grasping exponential growth? Why do some people have difficulty grasping the difference between plural **s** and possessive **'s**? Why do some people have difficulty grasping geography? Why do some people have difficulty grasping social skills? \*Because people are different. \* > [@Galileo](#): > > Then I say (and you can imagine that the person is starting to get irritated by now) “We double the height _every_ time we cut the sheets in half. Right? So, let’s see what happens if we do this 10 more times. We were at one inch, then 2, 4, 8, 16, 32, which is about 3 feet, then 64, 128 (with is about 10 feet), then 20 feet, then 40, 80 feet. And we have 30 more times to go.” > > At this point, they’re pissed off and they don’t want to guess any more. Already the answer is way bigger than they thought, they’re feeling stupid, and they don’t know what to say next. I reassure them by saying that practically nobody gets the answer right because the problem is deceptively hard. You give a poor impression of yourself socially, if this is truly how you approach people in real life. Do you think of yourself as a modern-day Socrates, or something? :rolleyes: ---
**Author:** ![Max\_the\_Immortal](https://avatars.discourse-cdn.com/v4/letter/m/6de8d8/32.png) [@Max\_the\_Immortal](https://boards.straightdope.com/u/Max_the_Immortal)\ **Post date:** [November 25, 2011, 6:17am UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/27 "2011-11-25T06:17:33Z")
> [@Galileo](#): > > (The example works better with inches rather than with millimeters.) How do you figure? ---
**Author:** ![Galileo](https://avatars.discourse-cdn.com/v4/letter/g/85e7bf/32.png) [@Galileo](https://boards.straightdope.com/u/Galileo)\ **Post date:** [November 25, 2011, 1:07pm UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/28 "2011-11-25T13:07:52Z")
> [@rachelellogram](#): > > Why do some people have difficulty grasping exponential growth? > … > \*Because people are different. \* Okay, but that’s not an explanation. > [@](#): > > You give a poor impression of yourself socially, if this is truly how you approach people in real life. Do you think of yourself as a modern-day Socrates, or something? :rolleyes: I’ve tried this about 6 or 7 times, one-on-one only with people who I was close to and who I knew would be good-natured enough to put up with it. The entire process takes about five minutes. Several of the people found it entertaining, but some did not. I was sensitive to the fact that some people were getting a bit irritated and I’m pretty sure that I didn’t offend anyone. Most of the time, I introduced the brain teaser within a broader discussion of exponential growth (e.g. population growth or compound interest in an investment portfolio) and I used it as an example of how outlandish and unintuitive some results can be. ---
**Author:** ![Galileo](https://avatars.discourse-cdn.com/v4/letter/g/85e7bf/32.png) [@Galileo](https://boards.straightdope.com/u/Galileo)\ **Post date:** [November 25, 2011, 1:12pm UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/29 "2011-11-25T13:12:31Z")
> [@Max\_the\_Immortal](#): > > How do you figure? The question asks how high the stack will be and, although you could express the answer in inches, it is more meaningful to express it in larger units. It’s more difficult to go from inches to miles than it is to go from millimeters to kilometers. That’s all. ---
**Author:** ![SecondJudith](https://avatars.discourse-cdn.com/v4/letter/s/b5ac83/32.png) [@SecondJudith](https://boards.straightdope.com/u/SecondJudith)\ **Post date:** [November 25, 2011, 2:08pm UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/30 "2011-11-25T14:08:12Z")
> [@Galileo](#): > > Everyone that I’ve asked will offer an answer that is not even close to the right answer. So, I’ll say something like this: > Let’s count how many sheets we have after each time that we cut the sheets in half. > (I start counting on my fingers, starting with my left thumb.)… > > Then I say (and you can imagine that the person is starting to get irritated by now)… > > At this point, they’re pissed off and they don’t want to guess any more. Cripes, I don’t blame them. Who are these people you’re asking and what situation are you asking it in? If we were hanging out drinking beer and suddenly someone came out with a patronising maths lecture and wouldn’t let it go, I’d be pissed off too. Is this what you do for fun? > [@Galileo](#): > > I reassure them by saying that practically nobody gets the answer right because the problem is deceptively hard. :rolleyes: I’m sure the condescension is thoroughly appreciated. ETA: > [@Galileo](#): > > Most of the time, I introduced the brain teaser within a broader discussion of exponential growth (e.g. population growth or compound interest in an investment portfolio) and I used it as an example of how outlandish and unintuitive some results can be. Seriously, I’m really quite curious as to how these conversations start. Do you just launch into this? ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [November 25, 2011, 2:12pm UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/31 "2011-11-25T14:12:30Z")
If you haven’t yet encountered it, read John Allen Paulos’ book **Innumeraxcy**. It’s many years old now, but it was a NYT bestseller, and its evaluation of the math skills of the general public is still spot-on. > **[Amazon.com: Innumeracy: Mathematical Illiteracy and Its Consequences:...](https://www.amazon.com/Innumeracy-Mathematical-Illiteracy-Its-Consequences/dp/0809058405)** > > Amazon.com: Innumeracy: Mathematical Illiteracy and Its Consequences: 9780809058402: John Allen Paulos: Books Not only do people have trouble with the exponential function, they have real difficulty with probability, essentially equating “one in a million” with 1% and the like. I suspect most people don’t understand that the Decibel scale and the Richter scale are really logarithmic, or understand them. ---
**Author:** ![Galileo](https://avatars.discourse-cdn.com/v4/letter/g/85e7bf/32.png) [@Galileo](https://boards.straightdope.com/u/Galileo)\ **Post date:** [November 25, 2011, 2:23pm UTC](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987/32 "2011-11-25T14:23:52Z")
> [@SecondJudith](#): > > If we were hanging out drinking beer and suddenly someone came out with a patronising maths lecture and wouldn’t let it go, I’d be pissed off too. Is this what you do for fun? Please read my response above to \*\* rachelellogram\*\*. I’ve never done this while hanging out with friends drinking beer, although I can imagine raising the question with a particular group of friends. > [@](#): > > Seriously, I’m really quite curious as to how these conversations start. Do you just launch into this? Some people actually discuss things about science, politics, finance, and even math. Not sure what you’re curious about. [Previous page](https://boards.straightdope.com/t/why-do-some-people-have-difficulty-grasping-exponential-growth/603987.md?page=1)