I Ching glossary

Change: 易, the word that gives the book its name. Tradition gives it three senses: change, simplicity, and what does not change.
Confucius and the Yijing: Tradition says Confucius wrote the Ten Wings and wore his copy out with study. Scholars see a far more complicated picture.
Constancy: Holding firm and upright on a right course. In its earliest use, the character 貞 also meant to put a question to the oracle.
Distress: 吝: a setback that chafes, an embarrassment or narrowness that leaves a bad taste. Milder than misfortune, but not to be ignored.
Duke of Zhou: King Wen's son and regent of the early Zhou. Tradition credits him with the texts of the six lines of each hexagram.
Earlier Heaven: A way of arranging the eight trigrams in a circle, each facing its opposite: Heaven at the top, Earth at the bottom. Tradition credits it to Fu Xi.
Four virtues: The four words that open hexagram 1: 元亨利貞. Tradition reads them as four qualities; many scholars read them as two phrases.
Fu Xi: The mythical sage of early China whom tradition credits with drawing the eight trigrams.
Good fortune and misfortune: 吉 and 凶, the two words the I Ching uses to say whether a course goes well or badly. They nearly always depend on what you do.
Great person: Someone of great moral stature and reach: a wise ruler, a teacher, someone able to guide. "It is favorable to see the great person."
Great river: The image of a great, risky undertaking. "It is favorable to cross the great river" says it's time to commit to something big.
Hexagram: A figure of six lines, each yin or yang, read from the bottom up. There are 64 of them, and each one describes a kind of situation.
Image: The short commentary that reads each hexagram as two images from nature and draws from them a lesson on how to act.
Inverted hexagram: The hexagram you see when you turn the figure upside down: the top line becomes the bottom one. It shows the same situation from the other side.
Judgment: The short text attached to each hexagram in the ancient book, summing up its meaning. It's the first thing you read in a consultation.
King Wen: The founding figure of the Zhou dynasty, whom tradition credits with the 64 hexagrams and the texts of their judgments.
King Wen sequence: The traditional order of the 64 hexagrams, from 1 to 64, used almost everywhere. It runs in pairs: each pair is a figure and its inversion or opposite.
Later Heaven: The arrangement of the eight trigrams in a circle that follows the seasons and directions: Fire in the south, Water in the north. Tradition credits it to King Wen.
Line positions: The six places of a hexagram, counted from the bottom up. Each has its own meaning, and tradition asks whether a line is correct, central and in resonance.
Line text: The ancient text attached to each of the six lines of a hexagram. You read it when that line comes up moving in your cast.
Line values: The four numbers you can get when casting a line: 6 (old yin, moving), 7 (young yang), 8 (young yin) and 9 (old yang, moving).
Lower trigram: The bottom three lines of a hexagram (1, 2 and 3). It's called the inner trigram and often speaks of what's going on inside you, the base, the beginning.
Moving line: A line cast as 6 (old yin) or 9 (old yang). It has reached its extreme and turns into its opposite, and its text weighs heavily in the reading.
No fault: 无咎: there's no error or harm to hold against you. One of the most frequent formulas in the I Ching, often coming after a risk.
Noble person: The figure the I Ching holds up as a model: someone noble by conduct, not by birth, who knows how to act as the moment asks.
Nuclear hexagram: The hexagram hidden inside another: lines 2, 3 and 4 make its lower trigram, and lines 3, 4 and 5 make its upper trigram.
Opposite hexagram: The hexagram you get by changing every line: each yin becomes yang and each yang becomes yin. It shows the other side of the situation.
Petty person: The noble person's opposite: someone short-sighted who chases immediate gain. Originally, simply the common people.
Plum Blossom: A way to get a hexagram without coins or stalks, from the date and hour or from the numbers of something you notice.
Primary hexagram: The hexagram that comes straight out of your cast, with its lines just as they fell. It describes the present situation, where you stand now.
Question: What you put to the I Ching before you cast. A clear, open question frames the reading and gives the answer its meaning.
Reading: A complete consultation of the I Ching: the question, the cast, the hexagrams that come up and what you make of them.
Regret: 悔: something to be sorry for that can still be put right. Its best-known form, 悔亡, says that regret vanishes.
Relating hexagram: The hexagram you get by flipping the moving lines of your cast into their opposites. It shows where the situation is heading.
Ruling line: The line that defines or governs a hexagram's character. It's often the fifth line, or the one line that differs from all the others.
Small Image: The brief commentary attached to each line text, explaining its meaning, nearly always by the place the line holds in the hexagram.
Stable line: A line cast as 7 (young yang) or 8 (young yin). It doesn't change: it helps build the hexagram, but its own line text usually isn't read.
Synchronicity: Carl Jung's idea that two events can be linked by meaning rather than by cause. It shaped how the West came to read the I Ching.
Taiji: The single principle from which, according to the Great Commentary, yin and yang arise, and from them the trigrams.
Ten Wings: The ten ancient commentaries attached to the core I Ching text, which read it in moral and cosmological terms.
Three-coin method: The most common way to consult the I Ching: you toss three coins six times, and each toss gives you one line, from the bottom up.
Trigram: A figure of three yin or yang lines. There are eight, each with its image (heaven, earth, thunder, water, mountain, wind, fire, lake), and two make a hexagram.
Tuan: One of the classical commentaries of the Ten Wings. It explains the judgment of each hexagram in terms of its trigrams and the positions of its lines.
Upper trigram: The top three lines of a hexagram (4, 5 and 6). It's called the outer trigram and often speaks of your surroundings, other people and how things unfold.
Use nine, use six: The seventh text found only in hexagrams 1 and 2. It's read when all six lines are moving.
Wenyan: One of the Ten Wings, devoted only to hexagrams 1 and 2. It unfolds their judgment and lines as lessons in character and conduct.
Yang line: The solid line (⚊) of the I Ching. It stands for what is firm, active and moving forward. In a cast it comes up as 7 (stable) or 9 (moving).
Yarrow-stalk method: The classical way to consult: fifty stalks are divided and counted out to produce each line. It's slow and deliberate.
Yijing (I Ching): The Classic of Changes: the Zhouyi together with its commentaries, the Ten Wings. It's the book known in English as the I Ching.
Yin and yang: The two complementary forces of the I Ching: yang is active, firm and bright; yin is receptive, yielding and shaded. Every line is one or the other.
Yin line: The broken line (⚋) of the I Ching. It stands for what is receptive, flexible and supportive. In a cast it comes up as 8 (stable) or 6 (moving).
Zhouyi: The core text of the I Ching: the 64 hexagrams with their names, judgments and six line texts, without the later commentaries.