# Developing a 'mental abacus'
**URL:** https://boards.straightdope.com/t/developing-a-mental-abacus/548153
**Category:** Factual Questions
**Created:** [July 27, 2010, 4:31am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153 "2010-07-27T04:31:51Z")
**Posts on this page:** 11
**Page:** 1
### Author:  [@rhysf](https://boards.straightdope.com/u/rhysf)
#### Post date: [July 27, 2010, 4:31am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153/1 "2010-07-27T04:31:51Z")
I saw an example of this on Griff Rhys Jones’s “Greatest Cities of the World” when he was in Hong Kong. Primary school kids were adding and subtracting strings of three figure numbers almost instantaneously in their heads while Griff was failing to keep up using a calculator.
I like the idea of possessing this skill but I’ve never used an abacus nor do I have any idea how difficult it would be to develop a mental abacus, but if eight-year-olds can do it, I’m guessing it’s achievable for the average adult with enough time on their hands.
Does anyone here have any experience with this? How hard is it to become proficient enough with an abacus that you no longer need a physical abacus any more? Are there differnt types of abacuses that are more or less suitable to this?
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### Author:  [@Indistinguishable](https://boards.straightdope.com/u/Indistinguishable)
#### Post date: [July 27, 2010, 4:37am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153/2 "2010-07-27T04:37:57Z")
Er, if it’s in your head, why does it have to be based on the mechanics of an abacus? Would you be open to any other method of carrying out mental arithmetic?
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### Author:  [@rhysf](https://boards.straightdope.com/u/rhysf)
#### Post date: [July 27, 2010, 4:53am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153/3 "2010-07-27T04:53:00Z")
Sure, so long as it’s fast and no harder to learn.
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### Author:  [@Indistinguishable](https://boards.straightdope.com/u/Indistinguishable)
#### Post date: [July 27, 2010, 5:02am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153/4 "2010-07-27T05:02:22Z")
Thing is, all an abacus does, essentially, is keep track of beads in a ones column, a tens column, a hundreds column, and so on, and you go through the columns adding/subtracting and carrying/borrowing in essentially the same way as you would probably already do arithmetic on paper or in your head anyway. If you have better visual memory than, uh, digit-string memory, then imagining the abacus could perhaps be helpful for keeping track of what’s going on, but I can’t see how it would make anything any faster.
So I’m afraid I don’t know what it is about the abacus method of mental arithmetic which makes it supposedly so fast, beyond, I imagine, practice. But you can practice anything, and you already presumably have a hell of a head start practicing however you currently do mental arithmetic.
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### Author:  [@Rhythmdvl](https://boards.straightdope.com/u/Rhythmdvl)
#### Post date: [July 27, 2010, 5:24am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153/5 "2010-07-27T05:24:55Z")
The rods on my mental abacus are very loose. Any time I try and add more than a couple digits together, they slip out and beads fall all over the place. Horrible. It’s fairly crippling, in that I can do some fairly complex math on paper but am utterly lost when it comes to mental math agility.
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### Author:  [@rhysf](https://boards.straightdope.com/u/rhysf)
#### Post date: [July 27, 2010, 5:25am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153/6 "2010-07-27T05:25:31Z")
I don’t know how why it works either, but, at least anecdotally, it does appear to be much faster than the way most people do mental arithmetic.
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### Author:  [@Superhal](https://boards.straightdope.com/u/Superhal)
#### Post date: [July 27, 2010, 6:15am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153/7 "2010-07-27T06:15:23Z")
Adding two 3 digit numbers in your head is simple. Add from left to right. Glance over if anything will carry. If not, it’s the sum.
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### Author:  [@rhysf](https://boards.straightdope.com/u/rhysf)
#### Post date: [July 27, 2010, 6:24am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153/8 "2010-07-27T06:24:24Z")
> [@Superhal](#):
>
> Adding two 3 digit numbers in your head is simple. Add from left to right. Glance over if anything will carry. If not, it’s the sum.
Right, but the kids in this show were doing it instantaneously. The teacher was rapidly reading out a list of numbers, each being subtracted or added to the last, and the moment he stopped, they all put their hands up with, presumably, the correct answer (at least, whoever he asked had the correct answer). I found it pretty impressive, especially in kids that young.
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### Author:  [@Koxinga](https://boards.straightdope.com/u/Koxinga)
#### Post date: [July 27, 2010, 6:59am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153/9 "2010-07-27T06:59:17Z")
I learned the [“chisanbop”](http://en.wikipedia.org/wiki/Chisanbop) method of adding and subtracting when I was a kid. Was that what the HK kids were doing?
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### Author:  [@Wendell\_Wagner](https://boards.straightdope.com/u/Wendell_Wagner)
#### Post date: [July 27, 2010, 7:35am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153/10 "2010-07-27T07:35:39Z")
There are a number of methods of mental calculation:
> **[Mental calculation](https://en.wikipedia.org/wiki/Mental_calculation)**
>
> Mental calculation consists of arithmetical calculations using only the human brain, with no help from any supplies (such as pencil and paper) or devices such as a calculator. People may use mental calculation when computing tools are not available, when it is faster than other means of calculation (such as conventional educational institution methods), or even in a competitive context. Mental calculation often involves the use of specific techniques devised for specific types of problems. People...
It’s not clear that the chisanbop method is any better than a number of others. Also, it’s not necessary to learn how to use an abacus (or even to have ever even seen an abacus) to lean chisanbop. Being good at mental calculation is a matter of learning a mental technique (or inventing it yourself). This takes some significant amount of time. Given the existence of calculators these days, why bother?
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### Author:  [@Hilarity\_N.Suze](https://boards.straightdope.com/u/Hilarity_N.Suze)
#### Post date: [July 27, 2010, 8:24am UTC](https://boards.straightdope.com/t/developing-a-mental-abacus/548153/11 "2010-07-27T08:24:08Z")
This guy (Art Benjamin) is kind of amazing. [Link](http://www.ted.com/talks/arthur_benjamin_does_mathemagic.html)