Do you still count on your fingers? | Hacker News Reader

Do you still count on your fingers?

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38 pointsHooke90 comments

I count difference between small numbers and enums on my fingers.

This includes e.g.

  - the distance between months
  - the distance between wall clocks

It's simpler for me to say "The number of months between March and September is... April, May, June, July, August, September, six." than "The number of months between March, 3, and September, 9, is 9-3 = 6," because I don't cache the numeric value of the months. Maybe I would if I were a Chinese speaker, where September's name is 九月 jiǔ yuè = nine month.

For wall clocks that wrap around midnight, it's simpler to count because it removes dealing with negative numbers.

I count the number of days in a month on my knuckles.

The months after July are named after numbers, but the names are from the old calendar when the year started in March.

The months after August are named after numbers.

July and August form the Caesarian section.

Ah, so October is the official month of births as it comes after this "c section". Pun intended.

/!\ Months are intervals and suffer from the off-by-one problem.

If you count from the 15th to the 15th, fine.

But if you start on March 1st, finishing in September means 7 months, not 9-3=6. That’s when my fingers help me visualize full months.

Yeah, I think that might well be why I stick to finger counting, so I don’t accidentally count the offset as the first step.

September is a funny choice to use as an example, because it is named after a number (sept-: prefix, 7). The wrong number, though.

So remembering this little tid bit would do more harm than good

All of the months with numerical prefixes are wrong by the same offset, though. So as long as you remember that as well, it can be useful. Particularly since they're the last ones and thus take the longest to count to.

This is because September used to be the seventh month. March was the new year and coinsided with spring planting, the spring equinox. At some point we switched from a solar calendar to a lunar one and that's when the new year month changed. Source for all this is the dead sea scrolls, see the book "Ancient Mysteries of the Essenes" for a deep dive on our calendar.

Sept, Oct, Nov, Dec. My favourite months, wish they still where 7-10.

I thought the reason is because they added two months named July and August after emperors, which offset all the numbers by 2. (Sept, Oct, Nov, Dec - 7, 8, 9, 10)

That happened later, well after January and February had been added. I think the twelve month Roman calendar was from pre-history so we don't know when or why it was done. July and August were Quintilis and Sextilis, five and six.

Yeah, seems like I mixed my calendar history up. Reading this set me straight: https://en.m.wikipedia.org/wiki/Roman_calendar

Thanks for the reply, it led me to look into it deeper.

so, for those who haven't heard it yet...

why do programmers get Halloween and Christmas confused?

because oct(31) == dec(25)

Same with Quartember, Quintober, Sextober, October, November, and December.

I check my knuckles if its 30/31 days in a given month. Start counting months on first knuckle while including the depth between knuckles as well. Height means 31, depth means 30.

I still do this as well. I never understood why the little poem was so popular. At that point it’s just coming down to rote memorization, as pretty much any month can be used in any order and it will still sound right.

The thing one does need to remember with the knuckle method is to count the end twice before going back the other way. July and August are both 31. I suppose this isn’t an issue if 2 fists are used, but I was taught to use one, so I could use my finger to track and feel the peaks and valleys.

What's wrong with the poem?

  Thirteen days have November
  April, May, and December.
  All the rest have thirty nine
  except for February when the weather is fine.

Works for me.

Never realized I could use my finger tips for doing the same.

I do this as well. It's very handy (no pun intended).

Although in general I also count the difference in months on my fingers, this particular example from March to September just automatically pops a "six" because they are both ends of financial quarters. "Three months after Feb?" I need to count. "Three months after March? That's the next quarter, so June."

As a fun reminder of how different people are, the months to me are basically only their numeric value, and if someone starts taking about October I think to myself "October? Oh ya, the 10th month, got it."

I even sing the 'abcdefg' song to infer letter sort order.

I generally lose track somewhere after P.

I generally lose track somewhere after "cookie monster": https://www.youtube.com/watch?v=lYIRO97dhII

For long time I thought that I don't know alphabetical order. Unless I realized it's on telephone numpad, and I know that.

I do this too. I can also start at L if my intuition tells me the letter(s) I'm testing come after L. But that's it - I have to start at L or A. I don't know why L and not some other letter.

The reason for L is probably because of the rhythm of the usual way the song goes. l, m, n... are rushed together because "elemenopee" is easy and fun to say quickly.

  ... a 
  b c d
  e f g
  h / i
  j / k
  l m n o p
  q / r / s 
  t / u / v
  w / x
  y and z

I don't even need the song for the first couple lines these days!

Probably also for memorization. If the song were linear, letters would all cuddle together in the little children’s mind.

It’s quite funny that, as a French native, we are all taught exactly the same song! Same pace, same tone, same elemenopy, but later in life, somehow y’all just smash tough/thorough/through/trough letters together, and we go on with our hon/hen/heim.

> same elemenopy

Why? The song actually works with French names of letters!

  a b c d e f g /
  h i j k l m n /
  o p q r s t u /
  v www x y-y z

with doublé-vey sung with a swing rhythm (♪. 𝅘𝅥𝅯 ♩)

I've been able to start at A, E, L, or T, and your explanation makes sense.

I usually know a letter is near one of those four, but not if it is before or after, so if I am looking for P for example, I'll start with T for a bit, realize I've gone too far, and start over at L in hopes of finding it.

So did "twinkle twinkle little star", or the alphabet song come first

I'm convinced my kids thought lmno was a single letter for a while.

Supposedly “ampersand” comes from when the alphabet song/rhyme used to end in “and ‘per se’ and”. School kids mushed it together into “ampersand”, and over time it became the name for &.

My almost 2-year-old does, and its name is "bah"

I still do this as well, I distinctly remember a time in my life where that song didn’t make sense to me though for a weird reason.

The l,m,n,o,p part is often sung very quickly so to my 5(?) year old brain I never understood where this “elemenopy” business came in and what it had to do with the alphabet. One day it clicked but for a while there I was just along for the ride!

I can relate to this kind of confusion. When your brain expects useful information encoded in a detail, BUTT the author just did it for some trivial reason.

I have had this same encounter (in Arabic though). And I still vividly remember when it all made sense (that would be 24 years ago)

It is delightful to be in a foreign country where English is not primary language but is taught and hear/see a little child rattling off the 'abcedefg' song.

I don’t count on my fingers, but that, I do. I can think through to some subset of the order to find a target letter but it’s usually faster to just run through the song quickly in my head, from the beginning, so that’s what I do.

I mean, it’s like 4s worst-case to find the letter anyway. I can “sing” it in my head fast. Not something I really need to work on making faster.

I like to think of the English alphabet as a singly-linked list.

I can mostly start at any letter, but it has to be forwards.

They can be a miniature sort-of-abacus. Keeping track of a number while you're scanning a lot of other things that occupy your mind. You can even sort of hold both the 10¹ digit and the 10⁰ digit on your hands if you're used to it, by semi-extending fingers or other methods, counting up to 100 and "physically" keeping the number in "memory".

Most of the time it's not necessary but if I'm particularly tired I use it sometimes.

This is pretty much it. I'll use my fingers if I don't want to keep a number in working memory.

The mini-abacus is how I use them as well. I was in a math competition where you were not allowed to use any scratch paper or make any stray marks on the test nor could you attempt to correct your mistakes with an eraser or trying to turn a 7 into a 9 or similar. There was nothing against counting on fingers, so there are time where I still calculate with my finger tips

I actually learned to count on binary with my fingers at some point. So i can technically count to 32 on one hand and 1024 using both.

It's been useful a handful of times (less than 5 times, not 32).

But it's fun, and not that hard once you learn the pattern.

Teaching people how to do 4 in finger binary is always a hit, too.

https://en.wikipedia.org/wiki/Knuckle_mnemonic

I still use this all the time

When my hands are occupied, I visualize the knuckles and count them. It's still easier than remembering the calendar.

What's the highest number you can count on your fingers?

When I need to do something repeatedly for a large number of times, I use my thumb to count the joints of my fingers, where the right hand is the "ones" and the left hand the "tens" column. In practice, I only go up to a hundred (ie. I use the first three fingers on each hand while counting - three on each finger, for 1-9), because decimal. But, the same system could get to 12x12 or 13x13.

A really neat alternative is to count on your fingers using binary. The right thumb is 0, the pointer 2, the middle finger 4, the ring finger 8, etc.

Amazingly, this gets you to over 1000 on your two hands, which is a really neat trick in the right setting. (Casually counting aloud off you fingers is great way to break the ice when you use binary - it is familiar but unexpected, dumb but smart.)

Yes, I do, all the time.

Even more than that, I use my fingers to multiply. When I was in grade school, I had a mental block about memorizing my multiplication tables. I just couldn't do it (and I still don't have most of them memorized, but much more now than then).

My teacher ended up teaching me a finger trick to let me quickly compute any multiplication from 6x6 to 10x10 and I use it to this day. This "one weird trick" was one of the most important things I learned when I was a young lad.

I found this webpage that explains it: http://mathsonline.org/pages/tablesFingers.html

I have to count on my fingers to calculate time and dates. Dunno why, but I can’t get it right otherwise

Off-by-one errors?

Except on leap years

If you were missing any fingers, it might lead to an interesting perspective on imaginary numbers.

It's a useful communication gesture if the topic of conversation calls for it.

Once you visualise a calculator in your head there's no need to count on fingers. But I've recently learned that there are people incapable of visualizing anything at all, so there's that.

you visualize a calculator and it gives you the correct answers when you type in various problems?

I will commonly count things in safety critical situations with my fingers. Usually accompanied by pointing. And with a second party watching.

A very common technique used in Hindu/Buddhist Japa Meditation is to count the phalanges/creases in each finger including the tip thus making 4x5=20 count in one hand. For each 20 count of the right hand use 1 phalange/crease of the left hand and thus you can easily count upto 20x20=400 in a single complete cycle.

Occasionally for routine small counting.

What I did find interesting is that I've used it more for Japanese especially when I'm in Japan. I've been very slowly learning Japanese and of course counting in Japanese. So if I'm ordering food someplace I try to either count (yen) change or figure out the amount of an item I'm ordering.

I remember when I moved to the U.K. and asked at my new workplace for some memory sticks. - How many do you need? - Two. And I raised two fingers accordingly. - Here, in the UK, you don't do that with your fingers.

That day I learnt something new about cultural differences.

Yes you do, you just do it palm facing the person you're talking to (known locally as the "victory sign").

“V for Victory” isn’t just a hand gesture, it was a WW2 meme of defiance. Curiously, Churchill used both hand orientations.

Who the hell signals two with your palm facing you? That's the only way you can get in trouble.

I do. Whenever I'm holding my fingers up to indicate a number, I do it with my palms facing me. I'm in the US, though, where there is no special meaning for the two-fingers-raised hand gesture no matter which way your palms face.

I get embarrassed counting on my fingers during exams. I can't seem to kick this habit.

During exams? Don't worry about it. Your fingers are a pretty effective L3 cache.

What's more embarrassing: counting on your fingers, or doing worse than you could've because you were worried about what other people think?

I'm feeling insecure about my math skills because I struggle with it.

Then deliberately struggling more isn't going to help you.

It's possible that you've reached the limit of your mental arithmetic ability (at least for now), but even professors of mathematics can struggle with mental arithmetic. Mental arithmetic is mostly important in school, and while shopping, but it's not really important for doing maths (especially not now we have calculators).

IIRC some cultures use a nifty method where the right hand is the ones column, the left hand is the tens column, and the thumb indicates five (sort of like an abacus).

Then each hand can represent 0 to 9, and together they go to 99.

Yes, counting rests (sections where I'm not playing) when playing in the band. That way, my fingers keep going even if I'm distracted by other things.

I suppose you could say I'm counting time, rather than things.

anybody remember this being pushed, K-TEL record style?

https://en.wikipedia.org/wiki/Chisenbop [circa.US 1977]

Yes! I use Chisanbop for basic counting, but I never learned the advanced stuff.

No, I count with my toes on both sides: 1 is all left toes and 2 is all right toes, 3 left again and so on. With a small break after each even number. I guess one could call it a tic.

I’ve noticed I count syllables on my fingers when writing in meter.

Sumerians counted to 12 on one-hand.

https://en.m.wikipedia.org/wiki/Sexagesimal

well technically you can count to 31 on one hand

The sexagesimal system used by the ancient babylonians and sumerians is believed to involve counting using the finger bones of our hand

I often count by a rhythm feel for smaller numbers. Maybe subdivide into rhythms of four and then count each of them manually.

When I want to count two things at the same time, sometimes I will count one of them by hand.

I count rests in orchestra by counting in finger binary, 31 on one hand is enough for a cello.

I still count days in months using my fingers. :)

I still use the knuckles method I learned as a kid.

Yes, in binary. Addition and multiplication.

This reminds me of something from the early Internet.

There was a video (Flash?) of someone counting in binary on one hand, with acapella background music that sounded (to my untrained ear) like maybe some Nordic folk song.

If anyone has a link, I'd love to see it again.

Update: I've learned that the song is "Ievan Polkka".

I'm still hoping someone has a link to the video though, just for nostalgia.

Yes. And, I count in binary to stop myself speaking in bullshit meetings.

chunking

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