Does anybody know how the rulers of the days and the planetary hours were created?

I know why Monday follows Sunday and Tuesday follows Monday and so on, but I do not know why Sunday is Sunday and not let’s say Friday. With other words how was this cycle started?

Dear Georgius,
as far as I know the romans dedicated every day to a god of planets. At that time they knew seven, included sun and moon. Maybe that was the reason why we have 7 days a week. In the roman languages for example we have dimanche in french for sunday that comes from dies dominica = day of the Lord because in christian history it is said, that was the day of resurrection Jesus. Saturday = samedi comes from jewish shabat, in english it is the day of saturn, in german it is Samstag, also comes from shabat. I don't know why they chose this order for the days of the week. After the moon comes the day of Mars, then Mercury, and so on. Shabat meens seven. Thats why Saturday originally was the last day of the week. In the christian world now sunday is the last da of the week,
Jakob

The sequence of the days of the week is predicated on the planetary hours that follow the so-called Chaldean order (the 'spheres' of the planets, based on their apparent velocity, from Saturn to the Moon). The ruler of the first hour in a day is the ruler of the day as a whole, so that the first hour of the first day is ruled by Saturn (giving Saturday); 24 hours later, the ruler of the hour will be the Sun (giving Sunday), etc.

But I believe that what Georgius is asking is how/when/why this cycle was created, as it has no observable physical correlate (unlike the transits of the celestial bodies through the zodiac or their phases with each other, etc). I have often wondered the same myself, and also whether, with all the changes occurring in calendar systems, there was never any disagreement on whether a day was in fact, as Georgius says, Sunday or Friday. But I am not aware of any such instances.

As an aside, at a conference in Ravenna last month, Jeffrey Kotyk gave a talk that touched on the introduction and use of the astrological seven-day week in medieval China. I remember him mentioning one Chinese author telling his readers, if they were uncertain what day of the week it was, to ask a Persian (that is, a Nestorian Christian, a prominent religious/ethnic minority at the time), as they always know.

The question remains, why did they (we) divide into 7 days at all and why do they divide at all? What is the sense of a week?

There are seven classical (visible) planets, which were taken by astrologers to govern/signify everything in existence, separately or jointly. So it seems natural that they should have looked for planetary rulers of time units as well, whether natural ones (such as days, months or years) or culturally defined ones (such as hours).

The division of time into days is understandable, even if the sidereal day is not exactly the same length as the solar day. The division into years is also understandable for similar reasons. It gets difficult with the month and with the week anyway. Rather, the quadrants still make sense because they are clearly recognizable, i.e. the seasons.

Thanks for the answers!

Yes, I’m aware of the Chaldean order and how planetreray hours and lord of days interact. And for me it is obvious that a week includes all seven lights and planets each one has one day and one week is approximately a quarter of a revolution.

Martin Gansten wrote: Mon Jun 17, 2024 2:32 pm But I believe that what Georgius is asking is how/when/why this cycle was created, as it has no observable physical correlate (unlike the transits of the celestial bodies through the zodiac or their phases with each other, etc). I have often wondered the same myself, and also whether, with all the changes occurring in calendar systems, there was never any disagreement on whether a day was in fact, as Georgius says, Sunday or Friday. But I am not aware of any such instances.

Thank you for this information!

I enjoy such discussions.

Sometimes, we overlook things that we take for granted, assuming they are just the way they are.

In my impression, when reading ancient Chinese books, there is never any mention of days of the week (seven days in a week) or even the Gregorian calendar (referred to as the Western or common calendar).

We use a lunisolar calendar. The lunar calendar is based on the phases of the moon, with each month beginning from the conjunction of the sun and moon (new moon).

The solar calendar is based on the position of the sun and is divided into 24 solar terms.

These calendars are closely related to agriculture.

Interesting information, Wei! Is there no reference to the seven planets and lights?

In ancient China, there was reverence for the sun, moon, and five planets (Jupiter, Mars, Mercury, Venus, and Saturn), integrating them with the theories of the Five Elements and Yin-Yang.

The Sun (Yang): Symbolizing brightness and strength.

The Moon (Yin): Symbolizing softness and time, with special worship during the Mid-Autumn Festival.

Venus (Tai Bai): Associated with the element of metal, symbolizing wealth and the God of War.

Jupiter (Sui Xing): Associated with the element of wood, symbolizing growth and spring.

Mercury (Chen Xing): Associated with the element of water, symbolizing wisdom and the north.

Mars (Ying Huo): Associated with the element of fire, symbolizing passion and war.

Saturn (Zhen Xing): Associated with the element of earth, symbolizing stability and centrality.

*Venus and Mercury are also classified as morning stars or evening stars, similar to the Western "orient" and "occident" distinction.

To my knowledge, Chinese astronomy primarily focuses on the 28 constellations (stellar systems)/Twenty-Eight Mansions and the North Star (&Big Dipper).

https://en.wikipedia.org/wiki/Twenty-Eight_Mansions

Georgius, your question has piqued my curiosity about the study of calendars and astronomy across different cultures. Unfortunately, my memory capacity, time, and energy are limited, and there are so many things I wish to explore. I also want to sleep, play around, experience life. There are so many things I want to do, but I can't do any of them well.

But there was nothing as 7 days (planets) a week?

Georgius wrote: Sat Jun 22, 2024 7:22 pm But there was nothing as 7 days (planets) a week?

As far as I know, there was no concept of a seven-day week in ancient China.

However, there was a system of holidays in place. You can refer to this article for more information, which is in Chinese.

https://www.mohrss.gov.cn/ldgxs/LDGXlao ... 86619.html