# Why do we pretend days, weeks, months exist? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [October 1, 2018, 9:43pm UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288 "2018-10-01T21:43:26Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [October 2, 2018, 1:40am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/21 "2018-10-02T01:40:47Z")
> [@Kimstu](#): > > Weeks are more arbitrary and more variable, although the 7-day week is probably at least partly inspired by the real and measurable lunar phases of new moon, full moon and half moons. The Ancient Romans used an eight day week. They also used really bad calendars. ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [October 2, 2018, 1:43am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/22 "2018-10-02T01:43:58Z")
Tomorrow is Tuesday. Proof: I’m having tacos tomorrow. QED. ---
**Author:** ![Spectre\_of\_Pithecanthropus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spectre_of_pithecanthropus/32/12343_2.png) [@Spectre\_of\_Pithecanthropus](https://boards.straightdope.com/u/Spectre_of_Pithecanthropus)\ **Post date:** [October 2, 2018, 2:15am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/23 "2018-10-02T02:15:01Z")
> [@Chronos](#): > > Because they do exist. Next question? Well, except for weeks, which are almost entirely artificial. But the other two are recurring astronomical events, as is the year. A month was basically the time it took the moon to go through a complete cycle of phases, or as we say in our more enlightened times, to complete its orbit around the earth. To make up the deficiency a day or two was added to eleven of the twelve months, and February lost a day or two just to make everything come out nearly “right” (i.e., a year being twelve months long). ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [October 2, 2018, 2:24am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/24 "2018-10-02T02:24:43Z")
I keep up with it so I’ll know when my birthday is. 😉 I’ll let you all in on it when it’s time. Gifts are appreciated, of course. ---
**Author:** ![Kimstu](https://avatars.discourse-cdn.com/v4/letter/k/ecd19e/32.png) [@Kimstu](https://boards.straightdope.com/u/Kimstu)\ **Post date:** [October 2, 2018, 2:33am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/25 "2018-10-02T02:33:21Z")
> [@begbert2](#): > > Based on how ‘seconds’ got named, a third would be 1/60th of a second. Which, obviously, it a measure of time we desperately need. We’ve already got it. In fact, not only “thirds” but “fourths”, “fifths”, etc., already exist as technical terms in English to refer to those fractional places in **any** sexagesimal (base-60) units, not just time units. Here’s [an example from a navigational table](https://books.google.com/books?id=Y2pbAAAAQAAJ&pg=PA257) in the 1760 _Astronomia Accurata; Or the Royal Astronomer and Navigator_ by Robert Heath: > [@](#): > > Hence, to find the proportional Sexagesimal true to Seconds, the Fourths may be rejected, or omitted, in the Computation, and as far as Thirds only retained. ---
**Author:** ![Folly](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/folly/32/3219_2.png) [@Folly](https://boards.straightdope.com/u/Folly)\ **Post date:** [October 2, 2018, 2:37am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/26 "2018-10-02T02:37:53Z")
> [@Dallas\_Jones](#): > > It is a convenient way to keep track of when we should bathe next. Well, that explains months, but what about the rest of them? ---
**Author:** ![Kimstu](https://avatars.discourse-cdn.com/v4/letter/k/ecd19e/32.png) [@Kimstu](https://boards.straightdope.com/u/Kimstu)\ **Post date:** [October 2, 2018, 2:38am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/27 "2018-10-02T02:38:19Z")
> [@Spectre\_of\_Pithecanthropus](#): > > A month was basically the time it took the moon to go through a complete cycle of phases, or as we say in our more enlightened times, to complete its orbit around the earth. :dubious: Ai-yi-yi. No, a lunar month is a **synodic** cycle, i.e., a return to the same relative positions of the moon, earth and sun. Not a complete revolution of the moon in its own orbit or **sidereal** cycle. The former takes slightly more than 29.5 days and the latter less than 27.5 days, so you can’t really use them interchangeably. ---
**Author:** ![Machinaforce](https://avatars.discourse-cdn.com/v4/letter/m/aeb1de/32.png) [@Machinaforce](https://boards.straightdope.com/u/Machinaforce)\ **Post date:** [October 2, 2018, 4:14am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/28 "2018-10-02T04:14:10Z")
The planning but makes sense and at least it’s not out of thing air but it has solid backing. I guess I have been interactioning with too many folks who “question everything” ---
**Author:** ![PlaceboTarget](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/placebotarget/32/1073_2.png) [@PlaceboTarget](https://boards.straightdope.com/u/PlaceboTarget)\ **Post date:** [October 2, 2018, 5:48am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/29 "2018-10-02T05:48:37Z")
> [@Machinaforce](#): > > Why do we act like these things exist? Isn’t it just changes in light? How do we divide such things in a manner like that? How do we decide how many days in a month? Would it apply if we weren’t on earth? Culture and civilization is broadly speaking the result of innumerable ideas that humans make up or come up with to satisfy their needs and cravings. Other animals pretend too but to a smaller extent. Due to their superior capacity of reflection, human beings can entirely reshape the social metabolism of their communities so that they can better control the environment and thus they eventually wind up living in an impossibly intricate web of conventions whose architectonics keeps them together as a group and controls them as individuals. ---
**Author:** ![BobBitchin](https://avatars.discourse-cdn.com/v4/letter/b/7ea924/32.png) [@BobBitchin](https://boards.straightdope.com/u/BobBitchin)\ **Post date:** [October 2, 2018, 7:54am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/30 "2018-10-02T07:54:19Z")
> [@burpo\_the\_wonder\_mutt](#): > > iswydt ;)Far out, man!:D:cool: I was so slick, man…I slid that one past myself, man.:smack:😃 ---
**Author:** ![Filbert](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/filbert/32/3433_2.png) [@Filbert](https://boards.straightdope.com/u/Filbert)\ **Post date:** [October 2, 2018, 8:01am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/31 "2018-10-02T08:01:40Z")
> [@elfkin477](#): > > Humans find it easier if we can agree on a name for an otherwise arbitrary block of time. Can you see what difficulty there would be in trying to coordinate to get things accomplished _with other people_ if we either had independent terms for a segment of time **or** no concept of time at all? You’ve met my hippy friends? ‘Five minutes’ can mean anything up to half a day… ---
**Author:** ![Sparky812](https://avatars.discourse-cdn.com/v4/letter/s/eb9ed0/32.png) [@Sparky812](https://boards.straightdope.com/u/Sparky812)\ **Post date:** [October 2, 2018, 11:24am UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/32 "2018-10-02T11:24:53Z")
> [@Machinaforce](#): > > The planning but makes sense and at least it’s not out of thing air but it has solid backing. > > I guess I have been interactioning with too many folks who “question everything” I hear ya… and also … why can’t we fill the world with silly love songs? What’s wrong with that? I’d like to know. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [October 2, 2018, 1:12pm UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/33 "2018-10-02T13:12:04Z")
> [@Ukulele\_Ike](#): > > Time was invented by the railroad companies in 1848, so they could tell if they were running on time. I thought it was Mussolini who invented that. Or that other guy-- what’s his name. ---
**Author:** ![JB99](https://avatars.discourse-cdn.com/v4/letter/j/439d5e/32.png) [@JB99](https://boards.straightdope.com/u/JB99)\ **Post date:** [October 2, 2018, 1:14pm UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/34 "2018-10-02T13:14:32Z")
> [@elfkin477](#): > > Humans find it easier if we can agree on a name for an otherwise arbitrary block of time. Can you see what difficulty there would be in trying to coordinate to get things accomplished _with other people_ if we either had independent terms for a segment of time **or** no concept of time at all? Have you ever been to the Middle East? ---
**Author:** ![RTFirefly](https://avatars.discourse-cdn.com/v4/letter/r/c77e96/32.png) [@RTFirefly](https://boards.straightdope.com/u/RTFirefly)\ **Post date:** [October 2, 2018, 1:17pm UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/35 "2018-10-02T13:17:52Z")
> [@Gatopescado](#): > > How else would we know when "Garbage Day’ is? 😕 In the Age of Trump, _every_ day is garbage day! 😉 ---
**Author:** ![RTFirefly](https://avatars.discourse-cdn.com/v4/letter/r/c77e96/32.png) [@RTFirefly](https://boards.straightdope.com/u/RTFirefly)\ **Post date:** [October 2, 2018, 1:20pm UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/36 "2018-10-02T13:20:56Z")
> [@Sparky812](#): > > I hear ya… and also … why can’t we fill the world with silly love songs? What’s wrong with that? I’d like to know. Excuse me, but I’m going off in search of something to drive that godawful song from my head. :eek: ---
**Author:** ![Sparky812](https://avatars.discourse-cdn.com/v4/letter/s/eb9ed0/32.png) [@Sparky812](https://boards.straightdope.com/u/Sparky812)\ **Post date:** [October 2, 2018, 1:45pm UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/37 "2018-10-02T13:45:55Z")
> [@RTFirefly](#): > > Excuse me, but I’m going off in search of something to drive that godawful song from my head. :eek: My apologies 😃 Maybe [this one](https://www.youtube.com/watch?v=DZN_8M4OpMo)is more appropriate? ---
**Author:** ![Fear\_Itself](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fear_itself/32/19637_2.png) [@Fear\_Itself](https://boards.straightdope.com/u/Fear_Itself)\ **Post date:** [October 2, 2018, 2:08pm UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/38 "2018-10-02T14:08:13Z")
> [@kayaker](#): > > Tomorrow is Tuesday. Proof: I’m having tacos tomorrow. QED. \ Tomorrow is Wednesday. ---
**Author:** ![Great\_Antibob](https://avatars.discourse-cdn.com/v4/letter/g/e47c2d/32.png) [@Great\_Antibob](https://boards.straightdope.com/u/Great_Antibob)\ **Post date:** [October 2, 2018, 2:18pm UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/39 "2018-10-02T14:18:15Z")
Well, at least the [French Revolutionary Calendar](https://en.wikipedia.org/wiki/French_Republican_Calendar) never caught on (lousy Thermidor weather!). ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [October 2, 2018, 2:21pm UTC](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288/40 "2018-10-02T14:21:14Z")
> [@Fear\_Itself](#): > > \ Tomorrow is Wednesday. Ahhhh, Proof: Margarita special at my favorite bar. QED [Previous page](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288.md?page=1) [Next page](https://boards.straightdope.com/t/why-do-we-pretend-days-weeks-months-exist/822288.md?page=3)