TL;DR: Liu Yao (also called Bu Yi or Liu Yao Prediction) is a method of interpreting the I Ching based on the six lines of a hexagram, assigning each line a Stem-Branch, a Five Element phase, a Six Relatives role and a Six Spirits quality, then weighing generation, restraint, strength, the day and month pillars, and movement. Because of that dense frame of reference, Liu Yao answers quantitative and identifying questions such as who, what, when and how much, while Mei Hua Yi Shu mainly answers questions about trend and timing through the body hexagram, the function hexagram and external omens. No method is absolutely correct; each school has its own strong and weak scope and should only be treated as a reference tool.
What is Lục Hào?
Lục Hào is a method of interpreting the I Ching based on the six lines of a doubled hexagram, in which each line is given an extra layer of information including Stem-Branch, Five Elements, Six Relatives and Six Spirits, and these layers are then examined for generation and restraint among themselves and against the day and month of casting. In other words, Lục Hào does not stop at reading the hexagram text and line texts; it turns the six lines into six calculable data cells.
It is worth separating two meanings of the term. In the narrow, classical sense, liu yao simply means the six lines of a doubled hexagram, that is, the six lines that make up the hexagram. In the broad, common sense used by I Ching researchers today, Lục Hào is the short name of a predictive method, usually called in full Bu Yi or Lục Hào Prediction, tied to a tradition many texts credit to Jing Fang (77 to 37 BCE) of the Han dynasty, with later generations adding to it.
The core point that sets Lục Hào apart: it does not only ask what the hexagram says, but asks what is winning, what is losing, and what is moving in this situation.
Where did Lục Hào come from in the I Ching?
The I Ching began with a system of yin and yang line symbols, from which three lines were stacked into the eight trigrams and two trigrams were doubled into the 64 hexagrams, each hexagram having six lines. Mathematically there are only two to the third, eight, combinations of three lines, and eight squared, 64, combinations when two trigrams are doubled, so the system is closed and consistent.
For many centuries, using the I Ching to ask about fortune was tied to yarrow stalks or coins, then reading the hexagram text and line texts. In the Han era, Jing Fang introduced a new structural layer: assigning the Stems to each line, giving it a Five Element phase, setting Six Relatives relations among lines, and adding the Six Spirits. From then on, later I Ching scholars revised the method, added rules, and it became one of the most tightly structured predictive systems in the Eastern tradition.
Alongside it, another branch is Mei Hua Yi Shu, tied to a tradition attributed to Shao Yong (1011 to 1077) of the Song dynasty. This branch does not assign Stem-Branch to lines or use the Six Relatives, but takes the body hexagram and function hexagram as its main axis, combined with external omens.
In Vietnam, both branches are known, but their popularity varies by setting. In classical I Ching books that have been translated and annotated, the hexagram text and line texts remain the common foundation for all branches.
How Lục Hào works: what are the six lines loaded with?
What are the lines and their order in Lục Hào?
Each doubled hexagram has six lines, read from bottom to top, line one at the bottom to line six at the top. This order reflects development from inner mind to outer circumstance, from root to tip. A yin line is a broken stroke, a yang line is a solid stroke.
When casting, each line receives a number. In the traditional yarrow stalk method, the result falls into four values: 6 is a moving yin line (old yin), 7 is a static yang line (young yang), 8 is a static yin line (young yin), 9 is a moving yang line (old yang). A moving line changes into its opposite line, producing a second hexagram called the changed hexagram.
What is Nạp Giáp and the Five Elements?
Each line is given a Heavenly Stem and an Earthly Branch according to a fixed Stem assignment table for each hexagram. From the Earthly Branch, the line's Five Element phase is derived. This step turns a yin-yang symbol into an entity with a concrete Five Element quality, for example a line belonging to Metal, Wood or Water.
What are the Six Relatives?
Taking the Five Element phase of the hexagram as the frame of reference, each line is assigned one of the six Six Relatives relations:
| Six Relatives | Relation to the hexagram line | Common meaning |
|---|---|---|
| Parent | generates the hexagram | parents, contracts, documents, house, protection |
| Sibling | same phase as the hexagram | siblings, friends, rivals, sharing or competition |
| Offspring | generated by the hexagram | children, fortune, medicine, removal of misfortune |
| Wealth | restrained by the hexagram | money, assets, wife, material resources |
| Officer-Ghost | restrains the hexagram | career, position, illness, pressure, obstructive party |
Despite the name, there are only five relations: six lines share five kinds, so one kind always repeats. Thế and Ứng are two line positions, not relatives: Thế is the person asking, Ứng is the party asked about.
This table is the backbone of Lục Hào. When asking about work, the reader looks at Officer-Ghost. When asking about money, look at Wealth. When asking about papers and contracts, look at Parent. When asking about health, look at Officer-Ghost together with Offspring and Self.
What are the Six Spirits?
The six lines are also assigned the Six Spirits according to the casting day: Azure Dragon, Vermilion Bird, Hooked Earth, Coiling Snake, White Tiger, Dark Warrior. The Six Spirits do not decide fortune or misfortune; they add nuance: Azure Dragon tends to joy and luck; Vermilion Bird to speech and disputes; Hooked Earth to slowness and stagnation; Coiling Snake to worry and tangled matters; White Tiger to force, pain and decisiveness; Dark Warrior to obscurity and concealment.
What do the day and month mean for strength?
The day and month of casting are called Sun and Moon, acting as the two largest weights. A line can be generated by the Sun and Moon, restrained by them, clashed, combined, strengthened or weakened. The final judgment is the combined result of the line's Five Element phase, Six Relatives, Six Spirits, moving or static state, and pressure from the Sun and Moon.
Because there are so many layers, Lục Hào allows much narrower and more specific questions than reading the hexagram text alone.
Why can Lục Hào answer questions that Mei Hua cannot?
What questions is Mei Hua strong at?
Mei Hua Yi Shu takes the body hexagram and function hexagram as its axis. The body hexagram represents the subject, the function hexagram represents the matter or object. Generation and restraint between body and function indicate the trend: function generating body is favorable, function restraining body is adverse, body restraining function means one can take initiative but must spend effort, body generating function means loss. Combined with external omens such as timing, direction, passersby and sounds, the reader can judge trend and timing.
Mei Hua's strength is speed, flexibility, no need for tools, and it suits questions like which direction will this matter go, when will it shift, should one advance or retreat.
What questions is Mei Hua weak at?
Mei Hua is weak at questions requiring concrete identification and quantification. For example: of two people involved in one matter, who decides; where is this sum of money, when will it arrive, how much will arrive; among the obstructive factors, which is the main one; at what stage does a third party intervene. With a structure of only body and function, Mei Hua struggles to separate subjects and to assign weight to each factor.
Why can Lục Hào do it?
Lục Hào handles those questions because it already has slots to place answers in:
- There is the Self line to locate the asking subject, the Other line to locate the object asked about.
- There are Six Relatives to classify matters by nature: money under Wealth, papers under Parent, career under Officer-Ghost, fortune and medicine under Offspring.
- There are Six Spirits to add psychological nuance and circumstance: disputes, delay, concealment, decisiveness.
- There are Sun and Moon to set strong or weak weight, from which timing and degree are inferred.
- There are moving lines and the changed hexagram to describe developments by stage.
In short: Mei Hua answers which trend, Lục Hào answers what, who, when and how much.
How do you phrase questions for each method?
To see the difference clearly, one can compare the same situation with two different ways of asking:
| Situation | Question suited to Mei Hua | Question suited to Lục Hào |
|---|---|---|
| Job application | Is this opportunity favorable, when is there news? | Will this position take me, who decides, is the salary as agreed? |
| Buying or selling a house | Will this deal succeed? | Is the seller sincere, are the papers problematic, in how many installments does the money come? |
| Health | Is this illness severe or mild, will it pass? | Where is the main symptom, does this medicine suit, when will it ease? |
| Litigation | Will this drag on or end quickly? | Which side has the advantage, which evidence is key, can it be settled? |
This table also shows something important: the two methods do not exclude each other. Experienced readers often use Mei Hua to grasp the broad trend, then use Lục Hào to dig into detail when needed.
Where do the schools disagree?
It must be said clearly: researchers and practitioners do not agree on many points, and this article only presents a description of viewpoints, without asserting which is correct.
- On the origin of yin and yang lines, there are several hypotheses: the reproductive-organ theory tied to Guo Moruo, the yarrow-stalk number theory, the oracle-bone numeral theory tied to Zhang Zhenglang, and a suggestion from Đông Sơn bronze drum patterns. No theory has been absolutely proven.
- On casting method, yarrow stalks and three coins give markedly different probabilities. Yarrow stalks give probabilities for moving yin, static yang, static yin and moving yang of 1 in 16, 7 in 16, 5 in 16 and 3 in 16 respectively. Three coins give 2 in 16, 6 in 16, 6 in 16 and 2 in 16. Some hold that only yarrow stalks are traditional, others hold that coins are convenient and still usable. Some variants such as the two-coin or improved three-coin methods are designed to reproduce the yarrow stalk probabilities.
- On the weight among information layers in Lục Hào, each school emphasizes a different aspect: some stress Sun and Moon, some stress moving lines, some stress the Six Spirits. There is no common standard accepted by all.
- On scope of application, some hold that Lục Hào should only be used for concrete, short-term, verifiable matters; others hold that it can be used for large matters too. This is more a difference of philosophy than of technique.
Learners should know which convention they follow, and should state that convention when presenting results, rather than presenting it as if there were only one correct way.
Both are reference tools, not guarantees of the future. They should not be used to replace practical decisions in finance, health, legal or other important matters.
