At a glance
- Basic arrangements
- Nine yang plus nine yin
- Direction
- Commonly yang forward, yin backward
Definition and terminology
A common hourly framework uses yang arrangements from winter solstice toward summer solstice, and yin from summer toward winter, with nine of each. Calendar transitions depend on method and are not always midnight switches. Traditional seasonal polarity language does not establish a measured energy scale or universal half-year suitability for action.
Structure and rules
Base-stem placement commonly follows forward yang and backward yin palace numbering, with the arrangement number giving the start. Solar terms are divided into upper, middle and lower subdivisions, linked with leader rules. Different methods reconcile five-day groups and term boundaries differently. Polarity alone does not construct every layer or specify every route.
Worked reading
Compare base placement: yang one begins Wu 1, Ji 2, Geng 3; yin nine begins Wu 9, Ji 8, Geng 7. The stem sequence remains while palace direction changes. Without an actual term, date and method, these are comparison tables, not assignments of those arrangements to a real moment.
Context and limits
Stories of legendary reductions of arrangement counts are transmission narratives, not proof of their historical events. When charts disagree, compare polarity, number, term timing and intercalation rules before interpretation. Solar terms are calculable and placement conventions reproducible; combining them does not automatically demonstrate reliable prediction of real events.
References & further reading
Historical sources document ideas and rules of their time, not empirical proof of predictive accuracy. Source notes identify the nature and scope of each reference.
- 《遁甲演义》卷一Primary / tradition source
Public-domain text for yin/yang arrangements, solar terms and eighteen arrangements; legendary origins remain legends.
- 《奇门遁甲统宗》Primary / tradition source
Public-domain received Qimen manual; documents palace, star, door and spirit rules and variants, not modern validation.