Would it be possible to convince the world to have 13 months with 28 days rather than having 12 months with different numbers of days every month?

Disregarding historical reasons for our current situation at the moment, here are my ideas why this would be useful.

It would be much more reasonable in my opinion, since the week has 7 days, so one would always know at which day one would have appointments just by knowing the date. Also, one would be able to plan into the future much easier, or look back to past events.

Even if one would argue with the moon phases, I think it wouldn't be a good argument, as one cycle take approximately 29.5 days, which doesn't fit with 30 and 31 days anyway.

I was wondering how it might be possible to implement this in our current society. Like how would one go about bringing public attention on this topic?


closed as off-topic by Renan, Gryphon, Giter, Confounded by beige fish., Mathaddict Mar 13 at 16:51

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    $\begingroup$ "Would it be possible to convince the world to have a new standard" xkcd.com/927 $\endgroup$ – Renan Mar 13 at 15:36
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    $\begingroup$ We have a hard enough time getting rid of daylight savings time; this would be a non-starter in current society. How to do it? Step 1: acquire dictatorial powers. $\endgroup$ – Gene Mar 13 at 15:42
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    $\begingroup$ you are not the only one to have this idea $\endgroup$ – Kepotx Mar 13 at 15:49
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    $\begingroup$ You do realise that people are still arguing about the pound vs kilogram, 200+ years after the latter was first standardised? $\endgroup$ – nzaman Mar 13 at 16:59
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    $\begingroup$ @F1Krazy, sadly worldbuilding.SE is often mistaken as the dump of SE: whatever doesn't fit a community is addressed here, just because. $\endgroup$ – L.Dutch Mar 14 at 6:43

The biggest problem with this idea is that it completely fails to take into account the way people use the calendar.

12 is a wonderful number, it divides easily many ways. You can divide your year into halves, thirds, quarters, sixths, twelfths, without really thinking.

13 is prime and hence useless.

This is why the idea will never get any traction.

  • $\begingroup$ It should be pointed out that the Calendar was originally 10 months (Hence September, the Seventh Month, Octoberm the Eighth Month, November, the Ninth Month, and December, the Tenth Month). However, 2 Roman Emperors decided that, like the gods Janus and Mars, of the goddess Juno , they too deserved a Month named after them. And not a dreary month at the end of the year - a bright cheerful and sunny summer month. So Julius Cæsar and Cæsar Augustus brought us up to 11 in 44BC and 12 in 8BC $\endgroup$ – Chronocidal Mar 13 at 16:11
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    $\begingroup$ @Chronocidal: "2 Roman Emperors decided etc.": This is fantastically wrong. Originally, named months stopped at June; then came numbered months, 5th (Quinctilis), 6th (Sextilis), 7th (September) and so on. Quinctilis was renamed July in honor of C. Julius Caesar, then Sextilis was renamed August in honor of Octavianus Augustus. Those were simple renamings, they did not add months. There is the shadow of a grain of truth in what you say; yes, loooong before emperors there were just 10 months, with the days between December and March not being allocated to a specific month, just "winter time". $\endgroup$ – AlexP Mar 13 at 16:23
  • $\begingroup$ @Chronocidal: The months September, October etc. are 7th, 8th etc. is because originally the year began in March. Fun factoid: until 1725, the English reckoned the years as beginning on 25 March. $\endgroup$ – AlexP Mar 13 at 16:26
  • $\begingroup$ I would not say that because 13 is prime it is useless. Kalam language, Kobon language both use a prime based number system. en.wikipedia.org/wiki/List_of_numeral_systems $\endgroup$ – Tolure Mar 13 at 16:33
  • $\begingroup$ @Separatrix I would think that this is pretty much the main, if not the only reason why 12 would be favorable to other numbers. But as already stated, it was probably not introduced because people needed two extra months to divide the year nicely. $\endgroup$ – Pink Panther Mar 13 at 17:30

It goes Viral

Trump, Trudeau, Warren Buffett, Snoop Dog, Weird Al, Bill Gates, and 20 other famous people (yes I know my list is western biased, this is not intentional) that anyone would at least know one of them is having a great party. All these people are arguing about what would be the best calendar out there.

At the end of it all, everyone is in agreement that to make calendars great again we need to change to [insert your system]. This video / audio recording / newspaper recount of what happened gets perceived by most people on earth. Towards the end you have a global shift towards your new system.

As long as the loud few care about your new system then eventually this should trickle down.


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