The Eight Trigrams (八卦) are a fundamental concept in ancient Chinese cosmology, philosophy, and metaphysics, originating from the ancient classic, the I Ching (易经, Book of Changes). Each trigram consists of three lines, either broken or unbroken, symbolizing the interplay of Yin and Yang forces. Together, the trigrams form a framework for understanding natural phenomena and human life.
PRENATAL EIGHT-TRIGRAM ORDER 先天八卦次序
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Xici Zhuan ctext states:
- In (the system of) the Yi (易) there is the Grand Terminus (☯TAIJI)
- which produced the 2 elementary Forms (⊖⚋YIN and ⊕⚊YANG)
- Those two Forms produced the 4 emblematic Symbols (⚌MAJOR-YANG, ⚍MINOR-YIN, ⚎MINOR-YANG, and ⚏MAJOR-YIN)
- which again produced the 8 Trigrams
- The 8 Trigrams served to determine the good and evil (issues of events), and from this determination was produced the (successful prosecution of the) great business (of life).
Shao Yong wiki states:
| EIGHT-TRIGRAM | ORDER | FORM | SYMBOL |
|---|---|---|---|
| ☰HEAVEN | 1st | ⊕⚊YANG | ⚌MAJOR-YANG |
| ☱LAKE | 2nd | ⊕⚊YANG | ⚌MAJOR-YANG |
| ☲FIRE | 3rd | ⊕⚊YANG | ⚍MINOR-YIN |
| ☳THUNDER | 4th | ⊕⚊YANG | ⚍MINOR-YIN |
| ☴WIND | 5th | ⊖⚋YIN | ⚎MINOR-YANG |
| ☵WATER | 6th | ⊖⚋YIN | ⚎MINOR-YANG |
| ☶MOUNTAIN | 7th | ⊖⚋YIN | ⚏MAJOR-YIN |
| ☷EARTH | 8th | ⊖⚋YIN | ⚏MAJOR-YIN |
PRENATAL EIGHT-TRIGRAM DIRECTION 先天八卦方位
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Shuogua Zhuan ctext states:
- ☰HEAVEN and ☷EARTH received their determinate positions
- ☶MOUNTAIN and ☱LAKE interchanged their influences
- ☳THUNDER and ☴WIND excited each other the more
- ☵WATER and ☲FIRE did each other no harm
- (Then) among these eight symbols there was a mutual communication. The numbering of the past is a natural process. The knowledge of the coming is anticipation. Therefore in the Yi (易) we have (both) anticipation (and the natural process).
Shao Yong wiki states:
| EIGHT-TRIGRAM | Resides in |
|---|---|
| ☰HEAVEN | South180°S |
| ☷EARTH | North0°N |
| ☲FIRE | East90°E |
| ☵WATER | West270°W |
| ☱LAKE | Southeast135°SE |
| ☳THUNDER | Northeast45°NE |
| ☴WIND | Southwest225°SW |
| ☶MOUNTAIN | Northwest315°NW |
POST-NATAL EIGHT-TRIGRAM ORDER 后天八卦次序
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Shuogua Zhuan ctext states:
- ☰HEAVEN is (the symbol of) heaven, and hence has the appellation of father
- ☷EARTH is (the symbol of) earth, and hence has the appellation of mother
- ☳THUNDER shows a first application (of ☷EARTH to ☰HEAVEN), resulting in getting (the first of) its male (or ⊕⚊YANG), and hence is called ‘the oldest son.’
- ☴WIND shows a first application (of ☰HEAVEN to ☷EARTH), resulting in getting (the first of) its female (or ⊖⚋YIN), and hence is called ‘the oldest daughter.’
- ☵WATER shows a second application (of ☷EARTH to ☰HEAVEN), resulting in getting (the second of) its male (or ⊕⚊YANG), and hence is called ‘the second son.’
- ☲FIRE shows a second application (of ☰HEAVEN to ☷EARTH), resulting in getting the second of its female (or ⊖⚋YIN), and hence is called ‘the second daughter.’
- ☶MOUNTAIN shows a third application (of ☷EARTH to ☰HEAVEN), resulting in getting (the third of) its male (or ⊕⚊YANG), and hence is called ‘the youngest son.’
- ☱LAKE shows a third application (of ☰HEAVEN to ☷EARTH), resulting in getting (the third of) its female (or ⊖⚋YIN), and hence is called ‘the youngest daughter.’
POSTNATAL EIGHT-TRIGRAM DIRECTION 后天八卦方位
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Shuogua Zhuan ctext states:
- God comes forth in ☳THUNDER (to His producing work)
- He brings (His processes) into full and equal action in ☴WIND
- they are manifested to one another in ☲FIRE
- the greatest service is done for Him in ☷EARTH
- He rejoices in ☱LAKE
- He struggles in ☰HEAVEN
- He is comforted and enters into rest in ☵WATER
- He completes (the work of the year) in ☶MOUNTAIN
Shao Yong wiki states:
- ☰HEAVEN governs the three sons in the northeast
- ☷EARTH governs the three daughters in the southwest
- ☰HEAVEN, ☵WATER, ☶MOUNTAIN, and ☳THUNDER are ⊕⚊YANG
- ☴WIND, ☲FIRE, ☷EARTH, and ☱LAKE are ⊖⚋YIN