The new and full moons dates are critical in all astrology! The current Four Pillars system for day counts is faulty and ignores the new and full moon effects.
Historic Tampering with the Ganzhi Sign of Year
Let us look at one historical incidence which shows that the imperial circle broke the continuity of the 60 cycle counts of the year. Lim et al (2000) noted the debate to replace the Yuanjia calendar:
- We will now give some details about the Yuanjia calendar, since that was the calendar which Zu Chongzhi sought to reform. Its author, He Chengtian, was probably the pre-eminent scholar of the early Liu-Song period... his Yuanjia calendar was the fruit of more than 40 years of research and astronomical observation. ... After 2 years of rigorous assessment by court astronomers, the Yuanjia calendar came into official use in the first month of 445.
However, Zu Chongzhi objected to the Yuanjia calendar and made new proposals (Lim et al 2000):
Yet, of the 11 calendars used since ancient times, none has put its Great Year 1 in a Jiazi year. For the new calendar, its Great Year 1 is a Jiazi year. Thirdly, a calendar should begin the motion of the heavens with the start of Great Year 1, but the Jingchu calendar only lists the time remaining from the start of Great Year 1 to the next node or perigee. He Chengtian's calendar even sets a different Year 1 for each of the 5 planets, while retaining the compromise of "time remaining to node" and "time remaining to perigee". Thus the only conjunction is in the sun and moon. This is haphazard and far from the level of perfection that the ancients aspired to. The new calendar introduces a method by which the paths of the sun, moon and 5 planets, as well as the node and perigee, all coincide at the beginning of Great Year 1.
- Firstly, we take Zi to be the first of the earthly branches, and its position to be due north. As for the lunar mansions, Xu is in the middle of the Northern Palace and therefore represents due north as well. Therefore the beginning of all things should have been from this point... For the new calendar, the sun's position at Great Year 1 is thus set at 1° within Xu. Secondly, Jiazi is the first combination of the stems and branches, and so a calendar should begin in this year.
Since the Taichu calendar of the Han, calendars had taken the winter solstice as the beginning of the solar or astronomical year, the new moon as the beginning of the lunar month, midnight as the beginning of a day. Besides this, the winter solstice was also taken as the starting point for the motion of all the heavenly bodies, and the Jiazi combination was taken as the first in the system of Heavenly Branches (Tiangan) and Earthly Branches (Dizhi). Therefore, the Great Year 1 had to begin at midnight on the new moon of the 11th month, on a Jiazi day, in which the heavenly bodies would all be in alignment at the winter solstice point. Obviously, such a year would be incredibly hard to find, and it would take a lot of astronomical guesswork, not to mention the likelihood of inaccuracy in older astronomical records. This might explain why, although a description of a Great Year 1 was given at the beginning of almost every Chinese calendar, the exact method of deriving it was never shown.
What Zu Chongzhi meant was that the ancient calendars had a beginning year called "Year 1", but that none of them attached the sign jiazi to that Year 1. He proposed that in future a new calendar should start during a period of the conjunction of 5 planets and it should be labeled with a jiazi sign.
Zu Chongzhi got his way when his proposal was implemented in the calendar in AD 465 (lLim et al 2000):
- stronger argument, but all the ministers of the court chose to agree with Dai Faxing out of fear of his political power. The only one who supported Zu Chongzhi was, strangely enough, Dai Faxing's colleague Chao Shangzhi. Perhaps, being himself a Palace Secretarial Attendant in the emperor's favour, Chao was keen on showing that he was Dai Faxing's equal. Whatever the case, Chao Shangzhi insisted that the new calendar was worth adopting, and the emperor was gradually won over to this point of view. Apparently, Liu Jun himself had a taste for unusual things, especially those with a sense of antiquity about them. Zu Chongzhi's advocacy of the ancient idea of the Great Year 1 may have appealed to him. He decreed that the new calendar would come into use in the following year, since he had planned to change his reign title anyway. By this time, the debate had dragged on for 2 years, and it was now 464 AD (the 8th year of Daming). Therefore the new calendar would be used from 465 onwards.
It is very important to realise that Zu Chongzhi did not apply the jiazi sign as a continuance of any preceding year count. Note: "Obviously, such a year would be incredibly hard to find, and it would take a lot of astronomical guesswork, not to mention the likelihood of inaccuracy in older astronomical records." There was no reliable basis in any preceding 60 cycle counts to name any year jiazi. The sign jiazi was just arbitarily applied to a period of the conjunction of 5 planets for administrative convenience, thereby breaking any potential previous count.
1984 is said to be a jiazi year. AD 465 to 1984 cover 1519 years. 1519 divided by 60 gives 25.317 cycles. 0.317 x 60 gives 19.02. If AD 465 was a jiazi year, then 1984 should be a Ren wu year (no.19) not jiazi (no.1). Even if the "conjunction of 5 planets" occurred a few years plus or minus, 1984 would still not be a jia zi year. Somewhere in between the year count was broken.
What the historical testimony shows was that when a new calendar was made, the imperial creator often broke the continuity of the 60 cycle counts and changed the Ganzhi signs. They would do it, not for astrological purposes, but for administrative convenience.