Hacker News Reader

Comment by jhbadger | Hacker News Reader

Doesn't anyone remember the old poem?

Thirty days hath September, April, June and November; All the rest have thirty-one, Excepting February alone. Which only has but twenty-eight days clear And twenty-nine in each leap year.

View on HN

I was taught the knuckle mnemonic, which I really like: https://en.wikipedia.org/wiki/Knuckle_mnemonic

I've always thought that this poem is useless as a mnemonic because a lot of the months have the same number of syllables and rhyme with each other. So remembering the poem is no easier than remembering the months directly.

The playground joke was "thirty days hath September; all the rest I can't remember"

30 days hath Septober, April, June and no wonder; all the rest have peanut butter, except for Grandma who has a red wagon.

to me the point of the poem is that it reminds you that there are 3 classes (30,31,feb) and the rhythm tells how many months are in each class. Remembering 4 booleans for which 4 are the 30 day months is easier than remembering 12 arbitrary integers (unrealistic worst case uncompressed memorisation technique)

I've never heard of it and it seems completely useless unless you're good at rote memorization (in which case you probably wouldn't need it): not only do some months have the same number of syllables and rhyme with each other, but also the order of the months in the poem seems completely arbitrary.

The knuckle mnemonic is how I learned it and while it doesn't help with remembering February, it's at least fairly foolproof because it still works if you get directions mixed up.

Songs and poems are easier to remember, at least for most people.

I can never remember it. I use the much less helpful method of knowing Julius and Augustus Caesar were megalomaniacs, so they have 31 days. February is special, and that just leaves 9 months of guessing.

That's actually not a bad place to start. If you know that months alternate 31 and less-than-31 days, then:

- working backwards from July you get May, March, and January have 31 days; -

- working forwards from August you get October and December have 31 days

Now you just have to remember that February is special.

Thanks. I feel like someone taught this to me when I originally learned the "Caesar must be best" method, but I lost the useful bit over time. Let's see how long it lasts this time!

Curious, in Spanish there's something similar. There are several variants, but the one I learned when I was a kid was

"Treinta días trae noviembre, con abril, junio y septiembre. Veintiocho, sólo uno, y los demás treintayuno".

It has the limitation that it doesn't tell you explicitly about February, but that one is easy to remember. Some people mock that mnemonic because they say that it seems harder to remember that the months themselves, but in my case, it has served me well.

Obviously there are similarities beyond chance, so I wonder which came first: the English version, the Spanish one, or maybe another from which both were inspired?

Wikipedia (https://en.wikipedia.org/wiki/Thirty_Days_Hath_September) mentions a Latin version:

  Junius Aprilis September et ipse November
  Dant triginta dies reliquis supadditur unus
  De quorum numero Februarius excipiatur.

But I'm not sure if this counts as the same poem or just another poem with the same information in it.

Googling turns up a French version "trente jours ont novembre" but I don't know if this is actually taught in French-speaking places.

French here, and father of kids in primary school.

Never heard of it.

We are using the knuckles version.

The Italian version is basically identical to this Spanish one:

  Trenta giorni ha novembre
  Con april, giugno e settembre;
  Di ventotto ce n'è uno,
  Tutti gli altri ne han trentuno.

I learned it a bit differently, although the first part about February is a bit clunky:

Thirty days hath September, April, June, and November All the rest have thirty-one, except February which has 28 Leap year comes one year in four, and February has one day more.

this is how i learned it as well, and still use it to this day

i find the knuckle mnemonic interesting but very difficult to use but i've only been trying it for the last 5 minutes

maybe its a visual issue and the same reason the poem has served me better

I have a shorter version:

Thirty days hath September, and the rest I can't remember.

But only on the century if it is divisible by 400.

https://www.explainxkcd.com/wiki/index.php/1595:_30_Days_Hat...

Reply on news.ycombinator.com