The moment you were born is a coordinate, not a conclusion.

1Four Pillars is a calendar

Four Pillars — 사주 in Korean — writes the moment of a birth as eight characters. Year, month, day and hour take two each. Four pillars, eight characters.

Its months turn on solar terms: the sun's position through the year. Building a chart is closer to astronomy than to fortune telling. There are no planets in it and no star signs, and it shares no lineage with Western astrology.

Of the eight characters, the first one of the birth day is the reference point. The other seven are read from where they stand in relation to it. That way of reading has carried on for roughly a thousand years.

2The calculation is exact. The interpretation is a hypothesis.

Same input, same chart, every time. Day pillars are checked against the values published by the Korea Astronomy and Space Science Institute, and match at all 15 anchors from 1930 to now — one inside every era when Korean legal time or daylight saving changed.

The first character of the birth day is the point the other seven are read from. If that one is wrong, everything read from it is wrong.

Interpretation is a different matter. That a classical text says something is not evidence that it is true.

So the reading asks you, sentence by sentence: is this you, or not? You are the one who decides.

3The clock is read twice

A solar term is a moment, not a reading on a clock: it is fixed by where the sun is. So the year and month pillars are compared at that moment, left as it stands.

The day and hour pillars are different. They are read from the standard-time clock of that place on that day, with daylight saving taken back out.

The first character of the hour pillar is derived from the character of the birth day rather than read off a calendar, so the eight characters cannot disagree with one another.

Solar terms follow the standard published by the Korea Astronomy and Space Science Institute.

4What we don't say

• Nothing you can buy to change it. No talismans, no rituals, no name changes.
• Nothing about what will happen to you in a given month or year.
• If the birth time is unknown, every sentence that depends on the hour is removed rather than filled in.
• Where the evidence is there, we get specific. Where it isn't, we stop talking.

5What you leave behind

What you tell the reading is stored apart from your name and your contact details. It is used anonymously, and only to check whether the reading was right.

It is never sold to anyone. Your private life is not advertising inventory.