Step one
排盤 (casting the chart): the shape of the moment you are asking about
Of the three steps this is the least mysterious one. It is pure calculation: give it a time and a place and there is exactly one answer, and anyone else working it out gets the same diagram.
It wants two things
When, and where. That is all.
Not your birthday, not your name, not your star sign — because it is not calculating you. It is calculating that instant, and in the same minute everybody gets the same chart.
Why the date on your calendar is not enough
“5 October” is a box on a grid we invented. What this uses is the solar term — where the sun has actually got to.
A solar term is not a day. It is an instant: the moment the sun reaches a particular angle. Cross it and the whole rule set for the chart changes — in the terminology, the cycle flips and the configuration number moves.
What that means in practice: eleven at night and one the next morning can produce two charts built on completely different rules, if the term happened to turn over in between. Being accurate to the minute is doing real work, not showing off.
Why where you are changes which hour you are in
Because clock time is something people agreed on. The sun did not agree to it.
Boston and Detroit run on the same clock, but Detroit sits far to the west of it — when a Detroit clock says noon, the sun is still some forty minutes short of overhead.
What the method needs is true solar time: where the sun has really got to. So it takes your longitude and corrects the clock back. After the correction, which two-hour branch you fall in (the old calendar splits a day into twelve of them) can change — and if the branch changes, so does the chart.
It is also why a chart looked up in a table will not match a computed one: a table does not know your longitude.
What is actually on the diagram
A 九宮盤 — the nine-palace grid: eight directions and the centre. Several layers sit in each square, each standing for a different side of the situation:
- 八門 — the eight gatesRoughly, what a person is doing — the action, the approach, how you go about it. The names sound auspicious or dire, but they are labels for positions, not verdicts. The “blocked” gate is not a bad gate; it is the one that means sealing every gap before you open anything.
- 九星 — the nine starsRoughly, the conditions of the time — the mood of the wider situation and which way it is drifting.
- 八神 — the eight spiritsRoughly, the human factor — who is helping, who is in the way, and whether anything is going on out of sight.
- 天干 — the heavenly stemsThe symbols that land in each square, standing for specific people and things — which one is you, which is the other party, which is the thing you asked about. This is what step two works with.
Two key positions also come out of it, the 值符 and the 值使: roughly, who is running this configuration and which door the work goes through. Where those two land decides where the chart's centre of gravity is.
Nothing has been interpreted yet
Casting only computes the shape of that moment and draws it. It has not answered anything. A chart showing the “death” gate does not mean you are in for a bad time, and one showing the “open” gate does not mean you are in for a good one.
Finding out what this chart says about your question is step two.
Makes sense — but you would rather not cast one yourself?
These three steps were always a fixed set of rules; they just used to run in a human head and pass from master to student. We hand the arithmetic to a computer and the explaining to AI. All you do is write down what you are weighing.
Write your question奇門遁甲 is a traditional Chinese practice for choosing timing. This page is background reading — not medical, legal or financial advice, and it will not tell you how anything is going to turn out.