Divide the lunar birth day by the bureau number. Once Zi Wei lands, the other thirteen follow.
The board and Five-Element Bureau are set. Now it is time to place the stars. This step gives Zi Wei Dou Shu its name: where you place Zi Wei star, the leader of the fourteen major stars, determines the entire chart.
The position of Zi Wei comes from just two pieces of information: your lunar birth day and the number of your Five-Element Bureau. This is where the number hidden in the Five-Element Bureau's name is used.
Here is the calculation. Divide the lunar birth day by the Bureau number. If it divides evenly, use the quotient. If not, add 1 at a time and divide again until it does. Two numbers remain: the quotient, and the added number needed to make it divide.
1. Born on lunar day 21 in Fire Six Bureau (6). Since 21 does not divide by 6, add 1 at a time. Neither 22 nor 23 works, but 24 divides evenly. The added number is 3 and the quotient is 4.
2. Set the Yin palace as 1 and count by the quotient. The fourth cell is Si (巳), which becomes the starting point.
3. If the added number is odd, move backward by that amount; if it is even, move forward by that amount. Here the added number is 3, so move back three cells.
4. From Si, move through Chen, Mao and Yin — the Zi Wei star lands in Yin (寅).
If the added number is 0 — in other words, the birthday already divides by the Bureau number — stay at the quotient position. Zero is even, so this is effectively “move forward 0 cells.”
Once Zi Wei is placed, Tian Fu (天府) follows immediately. Its cell mirrors Zi Wei across the board, so there is no separate count. The two stars can even meet in the same cell. From these two anchors, the other twelve stars at fixed intervals fall into place: six stars follow Zi Wei and eight follow Tian Fu.
Zi Wei Dou Shu therefore does not calculate each star one by one. Set the first anchor and all fourteen stars find their places at once. This is the opposite of Western astrology, which calculates every planet's observed position separately. This is what chapter 1 meant by stars being symbols placed by rules rather than measurements of the sky.
That completes the setup: twelve cells, the Life Palace, the Five-Element Bureau and fourteen major stars. From here, we move on to reading the finished chart.
Enter your birth date and time to see where your Zi Wei star lands and which Five-Element Bureau your chart uses.
This content is for reference and entertainment, based on traditional Chinese metaphysics and astrology.