I used to learn abacus and had do it for 2 years..
I am not sure if its me but I could've easily done 2 digit calculations in literal seconds... using the abacus model
Then our classes of abacus were shut and the thing is, that now I found myself a slight degradation because with abacus there was an assured confidence but then after abacus I used to blunder tiny things like 6+7=15 and 7*6 and other things.
Maybe my personal experience with abacus was how it ended. I had it for 4 semesters and got 4 medals in abacus for getting full marks but I still believe that it made my common maths, which it meant to improve a little weaker because well now although I don't pull up an abacus in my mind, I still have all the learning of basic things like 6+7=13 and other stuff but for some utter magical reason, learning abacus made me confuse it.
Overall it was a great experience though, seeing my cousins surprised that I was doing 2 digit numbers like 42x 37 calculation in 10 seconds in my mind while playing pass ball at 5th grade, maybe that was one of my peak achievements as I guess I have forgotten abacus completely...
I also remember one of my cousin saying that abacus looks like a music instrument and he used to make a little music out of it. Maybe fun times indeed. I remember it was the same day that I discovered the badlands biome in minecraft, maybe I was in 4th grade. Gold is really common in badlands, I remmeber going into the cave if I am correct.
Edit: also I meant not any hate towards abacus or maybe its just skill issue from my side and I just felt like saying it. I don't know why but for the most part although I still do these mistakes, I used to do it on a much higher frequency after stopping abacus and then covid hit and although I was a strong math student logically, I used to do some mathematical blunders.., for the most part they happen rarely now but still they sometimes do exist when my brain gets into too much auto pilot mode and I usually just prefer to solve calculations in the end because of this in any question or whatever, and maybe only just simplify things at most in intermediate steps so that I do least amount of mistakes possible. I usually don't think about this too much but I used to think that damn I am bad at this and used to remember the abacus past but then I saw some comments on reddit etc. saying that there were whole calculus phd teachers who sometimes did silly mistakes and maybe it was okay... felt really better about myself.
I've looked into this before. I gave up. It had little utility, even in daily life because humans make mistakes regularly. I have a mathematics degree so it's not like I can't do it but I quote one of my tutors "better to use a calculator than fuck it up and find out a page of working later". So I use a calculator.
I've got a soroban but never got around to learning it. Definitely should pick that up again.
When I was at Uni (electrical engineering) I noticed that the Chinese students would reach for their calculator way less than western students and assumed that was because of the abacus.
Side note: they tried to shape a control theory subject (everyone was getting 100%) by disallowing calculators in tests. It was rough having to do things like long division for the first time in decades. Still everyone got 100% haha.
Author here. Very surprised to see this on HN years after I stopped!
Also, thanks for the UI critique, points taken! The design decision was to hide nitty gritty detail about the background unless the reader was extra interested, in hopes of making an article with gradual / adjustable depth so readers who aren't as interested can get a tl;dr for each section (I still don't know how a nice UI to do this, although LLMs make the idea more in reach now).
Thanks for your articles. About your "The surprising benefits of disciplined, deliberate self-logging", I couldn't understand and it seemed cryptic how you're logging? The biologger.md is throwing 404. Could you explain?
Wow, thanks for digging! Looks like I haven't committed that file! It's an incomplete description of the android app that I wrote to output the jsonl in the self-logging piece going through some comparisons of existing options in 2019 and design decisions for the app. In short, it's like myfitnesspal tailored to my use case. 3 years later, the data is still a sprawl, but the logging strategy is stable.
Why the custom computer keyboard? Why not practice on a real soroban? They cost about US$10. You need to practice the finger motions, after all. They're not bad for addition and subtraction. For adding up small numbers, such as at a store checkout, a soroban is still useful. Multiplication, division, don't go there.
With a soroban and a slide rule, you can do most basic engineering problems.
Most people seem interested in this for mental math, but I think the correlation between Asia and mental math + abacus is spurious. All high level success in mental math comes down to is grinding/memorization, logic, and the knowledge of a handful of tricks. For instance somebody in this thread mentioned people finding impressive that they could multiply 42x37 in 10 seconds and attributed it to abacus work as a child. But this is really easy to do just using logic:
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Step 0 (plan) : We're multiplying 42x37. We need to find some simple (multiple of ten) numbers that are really close to the answer here, and then either subtract or add what's left over from our estimate. The most straight forward way to do this is to turn the problem into 42x40 - 42x3.
Step 1: 42 x 40 = 420 x 4 = 400 x 4 + 20 x 4 = 1600 + 80 = 1680
This process generalizes to basically any two numbers. And some otherwise scary sounding numbers make it really easy. For instance what's 87x99? It sounds hard but it's crazy simple because it's just 87x100 - 87 = 8700 - 87 = 8700 - 80 - 7 = 8620 - 7 = 8613, solvable in a second or two with practice. This is a 100% transferrable skill that will easily put you in the 'stupid human tricks' level of mental math - quite a fun 'trick' to have when teaching math!
For reference and comparison, one of the other mental math systems is the Trachtenberg system. Soroban is much faster, but Trachtenberg is quite reasonable to teach people of any age.
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[ 3.7 ms ] story [ 35.8 ms ] threadI am not sure if its me but I could've easily done 2 digit calculations in literal seconds... using the abacus model
Then our classes of abacus were shut and the thing is, that now I found myself a slight degradation because with abacus there was an assured confidence but then after abacus I used to blunder tiny things like 6+7=15 and 7*6 and other things.
Maybe my personal experience with abacus was how it ended. I had it for 4 semesters and got 4 medals in abacus for getting full marks but I still believe that it made my common maths, which it meant to improve a little weaker because well now although I don't pull up an abacus in my mind, I still have all the learning of basic things like 6+7=13 and other stuff but for some utter magical reason, learning abacus made me confuse it.
Overall it was a great experience though, seeing my cousins surprised that I was doing 2 digit numbers like 42x 37 calculation in 10 seconds in my mind while playing pass ball at 5th grade, maybe that was one of my peak achievements as I guess I have forgotten abacus completely...
I also remember one of my cousin saying that abacus looks like a music instrument and he used to make a little music out of it. Maybe fun times indeed. I remember it was the same day that I discovered the badlands biome in minecraft, maybe I was in 4th grade. Gold is really common in badlands, I remmeber going into the cave if I am correct.
Edit: also I meant not any hate towards abacus or maybe its just skill issue from my side and I just felt like saying it. I don't know why but for the most part although I still do these mistakes, I used to do it on a much higher frequency after stopping abacus and then covid hit and although I was a strong math student logically, I used to do some mathematical blunders.., for the most part they happen rarely now but still they sometimes do exist when my brain gets into too much auto pilot mode and I usually just prefer to solve calculations in the end because of this in any question or whatever, and maybe only just simplify things at most in intermediate steps so that I do least amount of mistakes possible. I usually don't think about this too much but I used to think that damn I am bad at this and used to remember the abacus past but then I saw some comments on reddit etc. saying that there were whole calculus phd teachers who sometimes did silly mistakes and maybe it was okay... felt really better about myself.
I've got a soroban but never got around to learning it. Definitely should pick that up again.
When I was at Uni (electrical engineering) I noticed that the Chinese students would reach for their calculator way less than western students and assumed that was because of the abacus.
Side note: they tried to shape a control theory subject (everyone was getting 100%) by disallowing calculators in tests. It was rough having to do things like long division for the first time in decades. Still everyone got 100% haha.
https://www.ee.torontomu.ca/~elf/abacus/feynman.html
And HN discussion: https://news.ycombinator.com/item?id=27934887
Also, thanks for the UI critique, points taken! The design decision was to hide nitty gritty detail about the background unless the reader was extra interested, in hopes of making an article with gradual / adjustable depth so readers who aren't as interested can get a tl;dr for each section (I still don't know how a nice UI to do this, although LLMs make the idea more in reach now).
It's really clean and good.
With a soroban and a slide rule, you can do most basic engineering problems.
-----
Step 0 (plan) : We're multiplying 42x37. We need to find some simple (multiple of ten) numbers that are really close to the answer here, and then either subtract or add what's left over from our estimate. The most straight forward way to do this is to turn the problem into 42x40 - 42x3.
Step 1: 42 x 40 = 420 x 4 = 400 x 4 + 20 x 4 = 1600 + 80 = 1680
Step 2: 42 x 3 = 40 x 3 + 2 x 3 = 120 + 6 = 126
Step 3: 1680 - 126 = 1680 - 100 - 20 - 6 = 1580 - 20 - 6 = 1560 - 6 = 1554
-----
This process generalizes to basically any two numbers. And some otherwise scary sounding numbers make it really easy. For instance what's 87x99? It sounds hard but it's crazy simple because it's just 87x100 - 87 = 8700 - 87 = 8700 - 80 - 7 = 8620 - 7 = 8613, solvable in a second or two with practice. This is a 100% transferrable skill that will easily put you in the 'stupid human tricks' level of mental math - quite a fun 'trick' to have when teaching math!