What a chart is made of

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This chapter does not teach you how to interpret a chart. It explains what a chart is made of — read it and you will know what each of those nouns in the output is talking about.

What charting does

Charting takes four inputs: the date of birth, the hour of birth, the gender, and a set of configuration switches that pin down school and boundary choices.

The output is a chart of fixed shape: twelve palaces, each with its own stem and branch, its own palace name, and however many stars land in it. This chart never changes for the rest of a life; it is called the natal chart.

On top of the natal chart, horoscopes are projected forward in time: which palaces and which mutagens govern this decade (the decadal), this year, this month, this day, this hour. Horoscopes change with the date you query.

date of birth + hour + gender + config
        │
        ├─→ natal chart (twelve palaces + stars + mutagens)   ← fixed for life
        │
        └─→ horoscope (decadal/age/yearly/monthly/daily/hourly) ← varies with the target date

Four concepts to get straight first

Stems and branches

Ten heavenly stems (jia, yi, bing, ding, wu, ji, geng, xin, ren, gui) and twelve earthly branches (zi, chou, yin, mao, chen, si, woo, wei, shen, you, xu, hai) are paired off in a cycle of sixty and used to number years, months, days and hours.

The four stem-branch pairs for a moment of birth are the four pillars — the geng chen - jia shen - bing woo - geng yin you see in the chart output.

Each of the twelve palaces also carries a heavenly stem of its own (the palace stem), which is what the flying mutagens are derived from.

Soul palace and Body palace

The Soul palace is the origin of the whole chart, located from the lunar month and hour of birth. The twelve palace names are laid out starting from it.

The Body palace is not a thirteenth palace: it is one of the twelve, additionally marked, and it indicates where effort is applied in later life.

Five Elements class

Derived from the stem and branch of the Soul palace. It is one of five values: water 2nd, wood 3rd, metal 4th, earth 5th, fire 6th. The number (2 to 6) is used twice further on:

1. Placing Ziwei: the lunar day is divided by the class number to fix which palace Ziwei falls in — and the positions of all fourteen major stars unfold from that one step.
2. Fixing the starting age of the decadals: water 2nd starts at nominal age 2, fire 6th at 6, and each palace governs ten years from there.

Mutagens

Each heavenly stem carries an assignment of four mutagens — Wealth (禄), Power (权), Status (科), Trouble (忌) — pointing at four specific stars. When charting, the birth year's stem stamps its mutagens onto the corresponding stars; each horoscope level then has mutagens of its own.

This is the main source of dynamic information in Zi Wei Dou Shu. See Mutagens and flying stars.

How the chart is laid out

A Zi Wei chart is twelve cells arranged in a ring, each cell owned by one earthly branch. The twelve palaces in the output are stored in a fixed order, and slot 0 is the Yin palace:

The twelve palace names (Soul, Parents, Spirit, …) are what charting computes: starting from the cell holding the Soul palace, they are laid out counter-clockwise. So "which cell holds the Soul palace" differs from chart to chart — which is exactly what the first step of charting decides. See The twelve palaces.

The layers of information on a chart

For the type and meaning of every field, see the Data model.

Read on