The Death and Life of the 13-Month Calendar | Hacker News Reader

The Death and Life of the 13-Month Calendar

citylab.com

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In grade school I would hold out for about a month after the switch to Daylight Savings Time: anytime somebody asked me for the time, I would provide it with an hour offset to what they were expecting, and when they quoted a time in their system, I was vocal about correcting it to the original time zone.

Somehow I was the nuisance for doing this, even though I think it’s quite clear that _they_ were the ones making time-keeping more difficult here - everything was working out just fine until they decided to change the meaning of 2pm for half of the year.

If we’ve somehow got an entire society that can play gymnastics with time in this way, and claim to wrap their head around it, I don’t think changing the calendar is really a huge ask. But I think the only way to pull it off is for the government to mandate its use. There's just not enough interest in fighting the currents for this to reach critical mass otherwise.

That said, I’m not convinced of the value of this calendar. Months are constructs that don’t have much meaning, but so are weeks - we could ax them both and just quote dates in terms of the numerical day within the year, for example. Or we could keep around weeks, but divide the year into quarters instead of months — that seems the most business friendly thing, and people already tend to think of the year in terms of four seasons outside of business; I wonder if Kodak considered it. Or, we could keep around the idea of weeks but rearrange them to be 10 days long to better fit with our decimal number system (7 days on, 3 days off? I might be amenable to that).

I guess months are valuable for businesses which provide long-term services and bill by the month, like ISPs or credit cards. But I’m hesitant to rebuild our time system to suit a business use-case that’s particularly widespread _today_ without some plan on how to easily change it when it no longer is useful. DST was founded in a similar way, and now we’re stuck with it for way longer than it ever made sense to keep it around.

>If we’ve somehow got an entire society that can play gymnastics with time in this way, and claim to wrap their head around it, I don’t think changing the calendar is really a huge ask. But I think the only way to pull it off is for the government to mandate its use. There's just not enough interest in fighting the currents for this to reach critical mass otherwise.

While we’re at it let’s convert to the Metric System too. Rip all the bandaids off at once.

Only if we switch to Base-16 at the same time.

While I agree in theory, in practice it’s still a bigger problem, as actual infrastructure needs to be changed for the metric system.

As was proven with the recent change of the DST dates, most calendars are handled by computers these days. It would be relatively straightforward to change the calendar.

There would be problems though. Monthly payments for things, for example, would need to be adjusted. So there would still need to be significant lead time.

Other countries have done it in modern times, the UK for one.

I’m just saying we shouldn’t connect the two, not that it’s impossible.

Also, the UK is far smaller than the US, making the infrastructure probably a bit more tractable.

How about the metric time system?

1 day = 10 hours

1 hour = 10 minutes

1 minute = 10 second minutes

1 second minute = 10 third minutes

Or should it scale at 1:100? Why or why not?

The French [0] tried to implement this twice! They failed both times, and I think it's due to more than having everyone in the world (or country) relearn to hold time in their head. Ultimately I believe it becomes less practical in day-to-day usage. 12 (and obviously 60, as a multiple of 12) can be divided by 2,3,4, and 6, while 10 can only be divided by 2 and 5. This would be the most difficult change for people, as a quarter or third of an hour are important metrics for daily life (I understand that seconds expand the divisibility for the sake of quarters (thirds remain unattainable), but this can happen in our current system and it's not often people speak in eighths of hours). I think this is a more common usage than the expansion of seconds-to-minutes, hours-to-seconds, etc. (a use-case where the decimal system really shines). Though, perhaps with the simplicity of the scaling, people would change their perspective on how they think/speak about time! It's definitely interesting to think about.

As an aside, I think this makes for a lot of practical uses for the imperial system of measurement. In a scale-intensive environment (science labs, kitchens, etc.), I think it would be foolish to not use metric. However, with small, one-off projects (mostly w/r/t length) I think it makes great sense to use feet and inches for halves, thirds, and quarters.

[0] http://mentalfloss.com/article/32127/decimal-time-how-french...

I built and android app just like this that marks ten hours, ten minutes, ten seconds and ten ticks being each tick 0.864 ancient seconds. Midnight starts at 000 and noon at 500.

Link?

Not the original poster, but I have decimal time as part of my (free) Android French Revolutionary Calendar app.

https://play.google.com/store/apps/details?id=com.ttaxus.the...

or the source https://github.com/jhbadger/Thermidor-Android

You must be from the US, Liberia or Myanmar.

Or the UK, where they drive in miles and weigh themselves in Stones.

In the USA, you can buy soda in liters and most cars use metric wrenches.

In the UK, you can buy pop in litres :)

>Or, we could keep around the idea of weeks but rearrange them to be 10 days long to better fit with our decimal number system (7 days on, 3 days off? I might be amenable to that).

Of all the things mentioned above this one won't be accepted by the general population, ever.

It was tried already in the revolutionary France, and is one of the few things that were rolled back.

> If we’ve somehow got an entire society that can play gymnastics with time in this way, and claim to wrap their head around it, I don’t think changing the calendar is really a huge ask.

It wouldn't even be the first time. September, October, November and December are _clearly_ meant to be 7th, 8th, 9th and 10th month. I always thought that July & August were the interlopers, being named after Emperors, but I read somewhere that I was wrong.

I share your frustration that there is a faction who seems to have dedicated their existence to making time as irregular as possible.

The history of the Roman calendar is somewhat unclear. The Julian reform is well-attested, as is the immediately pre-Julian calendar. This latter calendar is 12 months starting with January with day lengths of 29/28/31/29/31/29/31/29/29/31/29/29, plus an occasional intercalary month of 27 days whose insertion caused February to shrink to 23 days.

The Romans themselves maintained that before the Republican calendar, the year consisted of 10 months of alternating 30/31 days, with the winter months (of what would be January and February) consisting of a vague collection of days omitting a fixed month. But this explanation is dated essentially to people writing "what we used a millennium ago," and there's no attestation of this calendar much closer to its usage period.

In any case, it's definitive that the year used to start in March. When and why it transitioned to January is unclear. For what it's worth, even after most of Western Europe transitioned to using a Julian calendar, the starting date was quite inconsistent until very late. (England only switched in the 18th century, at the same time it adopted Gregorian calendar).

I had believed something similar. They are definitely remnants of a 10 month calendar, but July and August were existing months (Quintilis and Sextilis, respectively) renamed for the emperors. January and February appear to be the additions [0]. There is quite a bit of interesting history in the rest of that article about how the months have changed.

I can't remember if I'd read about a past society that did this, or it was an idea someone had proposed for a future one, but I love the idea of a 360 day year (12 months, 30 days each), with a 5 or 6 (leap year) day festival at the end commemorating the New Year. It would change birthdays for everyone born after January 30, which seems like it'd cause enough outrage to prevent it, but it's a fun thought!

[0] https://en.wikipedia.org/wiki/Roman_calendar#Legendary_10-mo...

Weeks are exceedingly important constructs! They're the whole reason any hare-brained scheme never amounted to anything.

They are used by religious communities. When your god says you must do something on Sunday or Saturday or Friday, you're not going to listen to anyone trying to tell you we don't need any of those. I mean you're fighting against multiple gods if you're trying to change the nature of weeks. Just like all the past attempts, you'll fail.

I am an atheist and I know this.

True. Even in my thoroughly atheist and liberal nation of birth I get payed double when I work on Sunday. I have no special feelings for it, Sunday or Monday its all the same to me. But thousands of years history and culture can't be erased easily.

I wonder why we haven't thought of a decimal calendar synced with the seasons like:

          W1 W2 W3 W4 W5 W6 W7 W8 W9
    SPR 1 10 10 10 10 10 10 10 10 10
    SUM 1 10 10 10 10 10 10 10 10 10
    AUT 1 10 10 10 10 10 10 10 10 10
    WIN 1 10 10 10 10 10 10 10 10 10 1 [1]

So we only have four months (seasons) and each has nine weeks of ten days each. Each season starts with a neutral day (equinox and solstice) then follow the weeks with ten days each. At the end of the year there is a universal holiday and an extra holiday for leap year.

We could also name all days of the week after the eight planets and the sun as initially intended (including moonday). We could have seven working days and three days off or three working days then two off then three more working days then two off per week.

Whatever, just wanted to leave a stinky brainfart in this room for posterity.

A season-based calendar, The World Season Calendar, was proposed by Isaac Asimov.

It consisted of four seasons, named A, B, C, and D, corresponding to Winter/Spring/Summer/Autumn in the Northern Hemisphere and Summer/Autumn/Winter/Spring in the Southern Hemisphere.

Each season looked like this:

  Sun Mon Tue Wed Thu Fri Sat
   01  02  03  04  05  06  07
   08  09  10  11  12  13  14
   ...
   85  86  87  88  89  90  91

That gives 91 x 4 = 364 days.

An extra day, called Year Day, occurs between D 91 and A 01 of the next year, and is not part of the 7 day week cycle. In leap years another extra day, also outside the week cycle, called Leap Day is added between B 91 and C 01.

We’d all ending up working 8 days a week... https://en.m.wikipedia.org/wiki/Eight_Days_a_Week

I like this idea. The novelty of “what day is holiday X this year” has long worn off.

Also found weird the author goes to so much trouble to explain then insults it in the last sentence.

The transition would be painful, but it would make so much stuff easier that we should just do it.

We would end up doing away with calendars. You would just know that the 16th is a monday.

Yeah, there's a bunch of stuff we should do to make things better in the long term. Unfortunately we seem to be stuck with short term thinking and can't even manage to transition away from daylight savings or imperial units or the penny...

This calendar would cause the seven-day week to get out of sync. I was curious about this some time back and couldn't find an exact history, but it certainly seems like the seven-day cycle has been maintained continuously for millennia - probably dating from Babylonian and early Jewish practice, then spreading to Europe via Christianity, without skipping/adjustments. The shift to the Gregorian calendar, for instance, removed days but kept the cycle of weekdays - in continental Europe, 4 October 1582, a Thursday, was followed by 15 October 1582, a Friday.

Wouldn't this proposal cause nations that adopt it to shift their weekdays from nations (and religions) that don't, at the rate of one a year?

> Wouldn't this proposal cause nations that adopt it to shift their weekdays from nations (and religions) that don't, at the rate of one a year?

Yes, and this is the primary problem with the 13mo/yr proposal, even more intractable than the constant month/day conversions between countries that would result. The "1 day of rest per week" (which is inseparable from the 7-day cycle) is very important to a large segment of the world's population, especially Muslims, Jews, and Christians.

Bingo! That's the whole crux of the problem there. You can't get rid of the 7-day cycle for religious reasons.

So when you try to create a universal calendar that satisfies all the religious constraints, you end up with ... something so close to what we already have that it's not worth the hassle.

Well, just subtract the week-month alignment and "Year Day" and you're good. I don't see any problem with adding a 13th month with 29 days instead of 28 -- where religions and countries want specific monthly calendars, they already have their own maintained forks.

Although the below nursery rhyme would be deprecated. That might be enough to kill it :)

    30 days hath September
    April, June, and November

    All the rest have 31
    But February alone

    Which hath 28 days square, and
    29 in each leap year

That or the fact that a lot of people are superstitious about the number 13.

That nursery rhyme is deprecated for the simple fact that it doesn't actually rhyme.

Where doesn’t it? Note “thirty-one” and “alone” are an eye rhyme. Should have spelled it out.

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

Also I’m not sure if I should have put the last “and” at the beginning of the last line.

First, a nursery rhyme is for kids so if it only "rhymes" on paper, then it's going to be missed by the audience (and it's only a rhyme in a metaphorical sense anyway). Besides that, square and year don't rhyme either when spoken or written. Further, while November and September may technically rhyme, they don't sound very rhymey to me. Maybe just because the -ber ending is so common in months and the part of the words that differ are three syllables back.

We already have leap years that add a day. The months have different lengths, so the days of the week fall on different dates all the time. More like it's always been out of sync, and this would bring it _into_ sync.

Yes - it would bring a lot of things into sync, but the tradeoff is that you wouldn't be guaranteed that seven days after a Monday is another Monday. That is true and has been true since before the Julian calendar even existed, as far as I can tell.

Strict 7-day weeks were a Jewish thing from sometime before 500 BC, unrelated to the Roman calendar. Even in other cultures that split time into weeks based on lunar phases, weeks were adjusted to match the moon (a lunar week is ~7.4 days).

From what I understand the Romans didn’t adopt a 7-day week as a core part of the calendar until after the emperor had converted to Christianity. See https://en.wikipedia.org/wiki/Nundinae

Yes, but leap years don't interfere with the fixed weekly succession of 7 named/numbered days.

I'm torn between preferring this (13x28+1) or a Coptic/Ethiopian calendar (12*30+5). Having each week start on the same day of the week is nice, but 12 months has advantages, too, and at least the first day of each month is consistent from year to year.

The Maya had 18 20-day months plus a 5-day intercalendary period.

A bit of a thought experiment: Do we really need years? In the past a calendar based on how long it took to make an orbit around the sun was useful for agricultural and other planning. Now we could have a 500 day cycle if we wanted to for some reason. Or maybe a hundred day cycle. Our ability to plant crops wouldn't be effected. There are many more variables involved now in determining when to plant or harvest than the Earth sitting at roughly the same spot as the last planting or harvest time. The Islamic calendar has long be out of sync with the solar calendar but still holds importance in Islamic culture. I'm sure there are others that likewise don't strictly abide by the solar year.

Instead of having a celebration on the day that the Earth is roughly in the same place in its orbit around the sun as it was when you were born, why not celebrate in increments of thousands of days you've been alive? Maybe broken down into once every hundred day celebrations before hitting the 5000 day celebration so children will experience them more often? I understand that some countries have a "Name Day" for the different common names in their culture, which is a celebration on par as one's birthday. We are very use to anchoring things to the orbital position on the Earth relative to the sun but we no longer live in a time where such things are of primary importance.

And don't even get me started on the possibilities of alternates to the primary school system being divided up into thirteen grades. Could each six week grading period (or a grading period of some other length) be its own grade? Do we really need to have so much of our culture and society tied so closely to the agricultural needs of the past?

Actually I think we do need years. It is kind of nice to know that the snowy season is typically dec-feb. That the warm summer months are July and August. And so on. Without having to do some mental arithmetic

Yes I think this is true.

I’m curious how future humans will relate.

You could imagine an intergalactic mission in which the calendar was kept as a keepsake from earth.

And if a new planet is colonized, would we work to stay in sync with earth in some way? Keep the same basic names but morph them?

What happens when two different civilizations meet with different calendars (we have some historical data on that).

if you’re talking intergalactic, you have relativistic time shearing effects to deal with as well.

You could do that without explicit years if you had a base 12 system.

The Mesoamerican long count calendar (which I'll call the Mayan calendar for short) counts days in a nearly-base-20 system. The nearly is because the second digit only counts up to 18 instead of 20, which means the nominally-400s-digit is actually counting near-years of 360 days. No intercalation was done to account for the year's length, and it's not because the Mesoamericans were dumb. The short count calendar was 18 months of 20 days with an extra 5 intercalated days (called Wayeb' in Yucatec Mayan), and there's no evidence for any kind of leap year correction, although the Mayans certainly did know that the year was around 365.25 days.

> A month is a wholly irrational division of time. It has no relation to anything in astronomy, ...

Well, except for its name. And its basis in the phases of the Moon.

https://www.etymonline.com/word/Month

A year or two ago I wrote a thing to generate up to date versions of these calendars based on the design of the 1928 Kodak one. https://github.com/dzucconi/a-month-is/blob/master/app/javas... & http://work.damonzucconi.com/a-month-is/?year=2018 (can change the year with the query parameter)

I love the idea, but in all honesty it would be a real problem making the week start on Sunday.

In all countries I've been but the States the week starts on Monday, not Sunday.

I love the logic behind it... although I guess quarterly planning would get a little annoying, since 13 isn't divisible by 4 or any number.

You have Jan 1 - Apr 7, Apr 8 - Sol 14, Sol 15 - Sep 21, and Sep 22 - Dec 28 (+ year day). Not the end of the world... but not exactly elegant either.

Planned month for paying down technical debt.

Just give everyone a month off. I see no problem with this :)

In my office, we run out projects based on calendar weeks. I keep thinking why can't we take this idea to the general public. It would make life a little bit simpler without having to bother about months and its irregular amount of days.

If this is what it will take to impose a 4-day work week then sign me up. :)

Explanation in the style of cpggrey https://www.youtube.com/watch?v=57G1Q8BW6Mw

Maybe I missed it in the article, do the four seasons start the same time every year? I assume they are adjusted, especially with Sol coming in the middle of Summer.

It's a 365-day calendar with the same leap-year rules as the Gregorian calendar, so yes, it should stay synchronized to the seasons.

I’m all for ditching the superficial Gregorian calendar, but do we really need inventing new one from scratch? There’s plenty of calendars out there, just pick one.

Not actually in favor of ditching the Gregorian calendar, but if you’re going to do it, this isn’t the worst proposal I’ve ever seen and at least one (formerly) major US corporation was able to make it work for them internally for just over 60 years. It wouldn’t make a difference if the calendar was from 1902 AD or 1902 BC as long as it could work for society. They’re all pretty much made up. You draw some lines in the sand till you have a calendar, denominate a few standard units of time labeling some of them with the names of the gods or Kings or Emperors or whoever and count upwards from there.

My only problem with making the switch to any different calendar is no matter how uniform or predictable, you’re breaking something that works pretty decently well to replace it with something that might be different, but probably isn’t actually better.

A calendar is a calendar is a calendar. We’ve gotten pretty good as a society, as a civilization, marking time on the Gregorian calendar, ticking off holidays and making plans around our availability. A change like this would benefit a small number of people at a large up front cost to society, and the supposed benefits for the masses at large ring more as superficial justifications to get this imposed by the government than any kind of genuine benefit.

lousy Smarch weather

Year-day would be the day when all computers stop. Truly an exceptional day!

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