The I Ching in 30 Pages
Heaven and Earth, Mountain and Lake: the Eight Trigrams
How can eight small signs hold the whole world?
Original
天地定位，山澤通氣，雷風相薄，水火不相射，八卦相錯。數往者順，知來者逆，是故易逆數也。In plain words
Heaven and earth set the places above and below; mountain and lake share their breath; thunder and wind stir each other; water and fire do not cancel each other out: so the eight trigrams interweave. Counting what has gone is going with the flow; knowing what is coming goes against it. That is why the Changes counts backward from the future.
Key words
- 八卦bā guàThe eight basic signs, each made of three yin or yang lines: Qian, Kun, Zhen, Xun, Kan, Li, Gen, Dui.
- 通氣tōng qìSharing breath: rain on the mountain runs into the lake; the lake's mist rises back to the hills.
- 象xiàngImage, symbol. One trigram can stand for a natural force, a family member, a body part, an animal and a quality at once.
Reading it step by step
Yesterday was yin and yang. Stack them three at a time and you get eight combinations: the eight trigrams. Two to the third power is eight; pair the trigrams into six lines and two to the sixth is sixty-four. In the eighteenth century Leibniz compared the traditional order of the hexagrams with binary numbers, though a similar idea is no reason to claim "the Chinese invented the computer." The real question is simpler: how can eight signs be enough?
First: the trigrams are four relationships, not eight objects. The text doesn't list them one by one. It pairs them. Heaven and earth "set the places": one above, one below, each where it belongs. Mountain and lake "share breath": rain on the hills runs into the lake, and the lake's mist rises back into the hills. Thunder and wind "stir each other." Water and fire "do not cancel each other out": they look like enemies, yet neither wipes out the other; the water in the pot boils because of the fire beneath. The world here is not a heap of parts but a set of things that need each other.
one above, one below
rain runs down, mist rises
each sets the other moving
opposites that leave each other be
Second: one sign, many meanings. A red light means stop: that is a signal, one sign for one thing. A flag or a name is a symbol: the same object means different things to different people at different times. The trigrams are symbols. Qian is heaven, and also the father, the head, the horse, strength. Kun is earth, the mother, the belly, the ox, yielding. Zhen is thunder, the eldest son, movement.
Gen is the mountain, the youngest son, stopping. There's an old rhyme for drawing them: Qian three whole lines, Kun six broken; Zhen a bowl facing up, Gen a bowl turned down; Li empty in the middle, Kan full in the middle; Dui open at the top, Xun broken at the bottom. The first gift of studying the Changes is a more flexible mind, one that stops expecting one word to mean one thing.
parents
three sons, three daughters
One symbol: a force of nature, a family member, a quality
Third: "the trigrams interweave" and "knowing what is coming goes against the flow." Eight times eight gives sixty-four situations. Counting the past is easy; you simply follow it. Seeing ahead means working backward from the present structure to where it is likely to turn next. The Changes was made for that harder job.
At home, you may know someone who holds the whole family up like heaven, someone who quietly takes everything in like earth, and someone who carries news between everyone like the wind. Once you see the images, you stop seeing any situation from one side only.
Next, we stack two trigrams and look at the six places their lines stand in.
Eight trigrams: not eight things, but four relationships.
Today's question
In your family or team, who is like heaven, who like earth, who like the wind that connects everyone? Which one are you?
Quick check
Why are the trigrams called symbols rather than mere signals?
A signal is one-to-one; a symbol shifts with context. Qian is heaven, and father, head, horse and strength.
I · How to Consult the I Ching — Yin and yang, trigrams, six lines, and how to ask a reading sincerely
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