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History behind the Japanese Days of the Week

milindindia

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30 Jul 2019
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I was wondering what the history behind the days of the week in Japanese, that are 月曜日 (Monday)、火曜日 (Tuesday)、水曜日 (Wednesday)、木曜日 (Thursday)、金曜日 (Friday)、土曜日 (Saturday) and 日曜日 (Sunday), containing the Kanjis of Sun, Fire, Water, Tree, Gold, Soil and Sun, is.

Also, coincidentally I noticed,
月 = Moon
火星 = Mars
水星 = Mercury
木星 = Jupiter
金星 = Venus
土星 = Saturn
日輪 = Sun (Well, this is generally called 太陽, isn't it? That must have a different story behind it.)
which use the same Kanji respectively.

Can someone tell the story, legend, history or mythology behind this?
 
In September of last year we had an article placed on this site with some slight updating, and there is information in that article that might prove of some research value to you, milindindia.


EDIT: And the link for the discussion: Article - The Japanese Calendar
 
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In September of last year we had an article placed on this site with some slight updating, and there is information in that article that might prove of some research value to you, milindindia.


EDIT: And the link for the discussion: Article - The Japanese Calendar

Thank you so much for this. :)
 
I was wondering what the history behind the days of the week in Japanese


日曜日 literally means Sunday.

月曜日 literally means Moon Day or Monday.

The names for the days of the week in both Japanese and English come from names of gods in Roman, Greek, Norse, and Germanic mythologies. The Japanese days of the week, such as Wood Day, Water Day, etc., may sound random but they are not. Care was taken to choose Japanese names that correspond to the same gods of mythology that were used to name the days in English.

You may be familiar with the Norse gods Odin and Thor. Odin's Day (Wodin's Day) is Wednesday, with an obvious sound similarity. The Japanese day is 水曜日 or Water Day. Odin in Norse mythology corresponds to Jupiter/Zeus, but in Roman/Greek mythology, Odin was mistakenly thought to correspond to the god Mercury. Mercury is a liquid metal and its symbol is water, so 水曜日 was chosen to represent Wednesday

Thor's Day is Thursday, again with an obvious sound similarity. The Japanese day is 木曜日or Wood Day. Thor represents Jupiter, and 木 represents the planet Jupiter, 木星.

Saturday is Saturn's Day. The Japanese day is 土曜日or earth/soil/dirt day. In Japanese the planet Saturn is 土星.

Friday comes from the Germanic goddess Frigg (Roman goddess Venus). In Japanese 金星 is the goddess Venus, so 金曜日 is used.

Tuesday is named for Tiw (Tiw's Day), a Norse god, but is named for the god and planet Mars in Latin-based languages. In Japanese 火星 is the planet Mars, so 火曜日 is used.

-------------

As was mentioned, the Chinese language does not use these mythology-based names, but uses numbers.

Monday 星期一 "day number one"
Tuesday 星期二 "day number two"
Wednesday 星期三 "day number three"
etc.

-------------

Sources (except for the names of Chinese days of the week):

etc.
 
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The names for the days of the week in both Japanese and English come from names of gods in Roman, Greek, Norse, and Germanic mythologies.

This explanation is convoluted, and for Japanese is incorrect, as the names of the weekdays in Japanese have nothing to do with the names of any gods from any of these mythologies.

Much more simply, the names of the days of the seven-day week, in both the west and in Japan, ultimately derive from what were once thought of as the "seven planets", but are now recognized as the sun, moon, and the five planets of the solar system visible with the naked eye. In Japanese, the five naked-eye planets are named based on the Chinese cosmological system of five elements (fire, water, wood, metal, earth). Yes, there is a correspondence in the naming of weekdays between Japanese and western languages, but this correspondence is due to the consistent use of the planets (and sun and moon) in the naming of the days, and not because of the names of any gods.

Mercury is a liquid metal and its symbol is water, so 水曜日 was chosen to represent Wednesday.

This is utterly bogus. The element was named for the god, and also has a connection to the planet Mercury, but the 水曜日 name derives from the Chinese five elements, not from the metal.
 
For a fascinating and surprising study of the influence of the Viking/Norse language (which is where the words Tuesday, Wednesday, Thursday, and Friday come from) on the English language, watch this video. (It is also interesting to note that Romance languages such as French did not receive this Norse influence, so their words for Tuesday, etc., are quite different.)

 
This is not bogus, it is not a coincidence that the Japanese names for the days perfectly align with the Western names for the days. It is completely illogical to assume that they would have a one to one association with zero previous contact. I am just curious when this contact happened. Were the days named during the Meiji restoration or before that? I think it's very interesting that so much of the world uses the same 7 day week and calendar which originated in Babylon, so it's not entirely a Western concept. It's more of something that was inherited in the Western world but that is also in place in other parts of the world even prior to modernization. It might be bogus that the days of the week were meant to align with English and not just the Babylonian calendar in general. So did the Japanese always use a 7 day calendar, did the 7 day calendar come to China from Babylon and then to Japan? Or did the 7 day calendar come to Japan and China in more modern times (the last 400 years or so) through contact with Western nations?

Actually I just googled this and found out that the Etruscans and thus the Romans originally used an 8 day calendar but switched to a 7 day calendar because that's what everyone else around them was using.
 
日曜日 literally means Sunday.

月曜日 literally means Moon Day or Monday.

The names for the days of the week in both Japanese and English come from names of gods in Roman, Greek, Norse, and Germanic mythologies. The Japanese days of the week, such as Wood Day, Water Day, etc., may sound random but they are not. Care was taken to choose Japanese names that correspond to the same gods of mythology that were used to name the days in English.

You may be familiar with the Norse gods Odin and Thor. Odin's Day (Wodin's Day) is Wednesday, with an obvious sound similarity. The Japanese day is 水曜日 or Water Day. Odin in Norse mythology corresponds to Jupiter/Zeus, but in Roman/Greek mythology, Odin was mistakenly thought to correspond to the god Mercury. Mercury is a liquid metal and its symbol is water, so 水曜日 was chosen to represent Wednesday

Thor's Day is Thursday, again with an obvious sound similarity. The Japanese day is 木曜日or Wood Day. Thor represents Jupiter, and 木 represents the planet Jupiter, 木星.

Saturday is Saturn's Day. The Japanese day is 土曜日or earth/soil/dirt day. In Japanese the planet Saturn is 土星.

Friday comes from the Germanic goddess Frigg (Roman goddess Venus). In Japanese 金星 is the goddess Venus, so 金曜日 is used.

Tuesday is named for Tiw (Tiw's Day), a Norse god, but is named for the god and planet Mars in Latin-based languages. In Japanese 火星 is the planet Mars, so 火曜日 is used.

-------------

As was mentioned, the Chinese language does not use these mythology-based names, but uses numbers.

Monday 星期一 "day number one"
Tuesday 星期二 "day number two"
Wednesday 星期三 "day number three"
etc.

-------------

Sources (except for the names of Chinese days of the week):

etc.
I think an easier way of saying this is that both the English and Japanese weeks were influenced by and correlate to Latin and the calendar used by the Roman empire. The Japanese week days correlate much more clearly to other European languages such as French, lunes (luna or moon), mardi (mars), mercredi (mercury), jeudi (jupiter), vendredi (venus), samedi (saturn), and dimarche. Dimarche mean's Lord's Day from Latin but prior to it's use in Rome that day was called dies solis which is where Sunday comes from in other languages such as English and German. I'm just saying, the Japanese week names are very Western but not particularly English.

And actually the weekdays and what planets they were associated with comes from Babylon so even then they are not actually a particularly Western concept.

Interesting, I just found out day is related to the word god in Latin: days (dies), 'gods' (deus, ablative plural diis). Because the days were named after gods. So the di in French is like day even though day in French is jour.


This is somewhat answers some of my questions although it was pretty confusing to read. But I did get that the Japanese were using the Babylonian calendar for astrology since year 1000 and that they adopted it in it's current form during the Meiji restoration. And that some other calendars are loosely based on the Babylonian calendar but aligning the planets with their own gods, although some cultures just use numbers and a few very remote ones don't use the planets or numbers.
 
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Dont be silly.... Chinese Astronomy uses 七曜 (7 luminaries) concept starting from East Han Dynasty, approx. 2 BC. All east asian traditional astronomy has long adopt same approach in describing astronomy existence

A 17s century Chinese book about translation of Persian Calendar into Chinese Calendar 《回回历法释例》, seem to suggest this linkage of Western Tradition (7 days a week) to Eastern Asia Tradition 七曜(7 luminaries) began even before then.

The book 1 section 3rd topic named: Explaining the number expression of 7 luminaries and its original name (in Persian, but here wrongly translated as 回回, which means Muslim in 17th Century China).

Original text written as :
释七曜数及本音名号
日一数【名也闪别】·月二数【名都闪别】·火三数【名写闪别】
水四数【名察儿闪别】·木五数【名盘闪别】·金六数【名阿的那】
土七数【名闪别】

In table it translates as follows:

7 Luminaries & --- Vocal Note of --- Latinized Persian --- Modern Wk
Numeric Value --- Original Name --- Pronunciation (Meaning) --- In English
------------------------------------------------------------------------------------------------------------------
日一 (Sun =1) --- 也闪别 (YeShanBie) --- Yek-shanbeh (1st Full-day) --- Sunday (Sun-day - Roman God)
月二(Moon=2)--- 都闪别 (DuShanBie) --- Do-shanbeh (2nd Full-day) --- Monday (Moon-day - Roman God)
火三 (Fire=3) --- 写闪别 (SieShanBie) --- Se-shanbeh (3rd Full-day) --- Tuesday (Norse God)
水四 (Water=4) --- 察儿闪别 (CharShanBie)--- Chahar-shanbeh (4th Full-day) --- Wednesday (Norse God)
木五 (Wood=5) --- 盘闪别 (PanShanBie) --- Panj-shanbeh (5th Full-day) --- Thursday (Norse God)
金六 (Metal=6) --- 阿的那 (ADiNa) --- Adineh (Gathering) --- Friday (Norse God)
土七 (Soil=7) --- 闪别 (ShanBie) --- Shanbeh (A day & night) --- Saturday (Saturn Day - Roman God)

See first column and last column (middle columns are the Persian Pronunciation and its original words meaning, which has no relation to astronomy at all, but counting day by day. This is the same for Hebrew, Latin, Arabic and Greek language, with only minor variance for religion days in a week). The 七曜 7 Luminaries as a Text-Numeric Value have long been linked to the western calendar tradition of 7 days= a Week starting from Ming Dynasty, approx. BC 1300s.

The fact is, although dividing 365 days as 7 for a week have been a western Asia and European tradition, the use of the 7 Luminaries 七曜 as numeric value to resemble each of these days, have been a self developed, pure Eastern Asia tradition, as an attempt to internalize multi-source cultures.
 
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I'm starting to get slightly confused. Let's continue this thread without calling people silly. It's an interesting discussion. No need to belittle anyone. So there are four possibilities

1. Days of the week developed independently in Asia and Europe. The fact that they both use planets as references (and in the same order) is purely coincidence.
2. The 7 days developed in the west, which was then borrowed by, or imported into, the East.
3. The 7 days developed in the East, and was them imported into the West.
4. The 7 days were developed by the Persians, who then spread it to both East and West.

So @Disjtu are you saying the names derived from #4?

In Heian Japan, there were other systems for counting the days of the month. The use of the 7-day week was known an used, but there were also other systems in use as well. The use of the 7-day week wasn't universal until Meiji (if I'm not mistaken).
 
I should say in addition to Persia being a common root for the 7-day week and the names of the weekdays, another possibility is Babylonia.
 
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