Why Three Coins Instead of Yarrow Stalks: The Method Behind Liu Yao Casting

If you have only encountered the I Ching through Western introductions, you may have learned the yarrow stalk method: forty-nine stalks, a careful sequence of divisions and counts, twenty minutes per line, two hours per hexagram. It is described in the I Ching's own commentaries, and for centuries it was the method of choice for scholars and ritual practitioners.

If you have ever seen anyone actually cast a hexagram in contemporary Chinese practice, you have almost certainly seen them use three coins. The coin method takes about thirty seconds for a full hexagram. It is faster, more portable, and produces results that are easier to share with a remote reader.

The question of which method is "more authentic" is one of the most common asked by Western readers approaching Liu Yao. The honest answer is: both are authentic, both are used by serious practitioners, and the differences are real but smaller than the question implies. This essay walks through what the two methods actually do, what the probability differences are, and why the coin method became the standard in contemporary Liu Yao practice.

For the foundation essay on Liu Yao itself, see What is Liu Yao? The classical Chinese hexagram method.

What both methods are trying to do

Whatever the casting method, the goal is the same: generate a hexagram of six lines, each of which is in one of four states.

• Old yáng (9) — solid line, changing to broken
• Young yáng (7) — solid line, stable
• Young yīn (8) — broken line, stable
• Old yīn (6) — broken line, changing to solid

The "old" lines are the changing lines, and they are the heart of the reading. (For more on why, see Reading the Changing Line: What Most Translations Miss.)

Both yarrow stalks and three coins are ways of producing one of these four numerical results for each of the six positions in the hexagram. The mechanism is different; the output is the same kind of thing.

The yarrow stalk method

Yarrow stalk casting is the older method, described in the Xìcí Zhuàn (the Great Commentary, one of the Ten Wings of the Yìjīng). The procedure uses 50 stalks of yarrow (Achillea millefolium); one is set aside, leaving 49 working stalks.

The casting of a single line involves three rounds of division. Roughly:

1. Divide the 49 stalks into two random piles
2. Take one stalk from the right pile and place it between the fingers of the left hand
3. Count off the left pile in groups of four; place the remainder (1–4 stalks) between fingers
4. Count off the right pile in groups of four; place the remainder between fingers
5. Set aside what is in the left hand; combine the remaining stalks and repeat the process twice more

After three rounds, the number of stalks remaining (divided by four) gives a value of 6, 7, 8, or 9 — which is the line.

For a full hexagram, this is done six times. A careful yarrow stalk casting takes roughly two hours.

The method is contemplative by design. The slowness is part of the practice — the reader holds the question in mind through the entire sequence, and the casting itself becomes a kind of meditation.

The three-coin method

Three coins is dramatically simpler.

Take three coins of the same kind. Assign each side a value: heads = 3, tails = 2 (or the reverse, by convention). Toss the three coins once; sum the values. The total will be 6, 7, 8, or 9 — which is the line.

Repeat six times, recording lines from the bottom up.

That is the entire method. A full hexagram takes thirty seconds to a minute. It can be done with any three coins (traditional Chinese coins are common but not required), and the casting can be done anywhere — on a desk, in a car, sitting on a park bench.

In contemporary Liu Yao practice, three coins is the standard. A remote reader receives the questioner's six line values, plugs them into the hexagram, and reads the casting.

The probability difference

Here is the technical point that often gets raised. The two methods produce different probability distributions for the four line outcomes.

Yarrow stalks (classical probabilities):

Three coins (standard probabilities, with heads = 3, tails = 2):

The two distributions are not the same. The yarrow method weights young yīn most heavily and old yīn least; the coin method is symmetric, with the two changing-line outcomes (old yáng and old yīn) each appearing 1/8 of the time.

The practical consequences:

• Changing lines are slightly more common with coins (1/4 per line, on average) than with yarrow (1/4 per line as well, but distributed unevenly between old yáng and old yīn)
• Old yīn (broken changing to solid) is dramatically more common with coins (1/8) than with yarrow (1/16)
• The yīn-yáng balance is different — yarrow weights stable yīn over stable yáng (7/16 vs 5/16), while coins weight them equally

Some practitioners argue the yarrow probabilities are more aligned with the I Ching's underlying symbolism (yīn as the receptive, the more frequently encountered base state of the world; old lines as the rare events of pivotal change). Others argue the coin probabilities are cleaner and more usable. Both arguments are made by serious people.

What is empirically true: both methods produce castings that practitioners read as meaningful, and the divinatory practice does not collapse under either probability distribution.

Why the coin method became standard

If yarrow stalks are older and have a stronger claim to classical authority, why does almost everyone use coins now?

Three practical reasons:

1. Speed and accessibility

A coin casting takes thirty seconds. A yarrow casting takes two hours. For a working practitioner reading multiple questions per day, or for a questioner casting on their own situation, the time difference is decisive.

This is not laziness. The contemplative dimension of the yarrow method is real, but it was developed in a setting (scholarly literati, ritual practice) very different from how the I Ching has been used in popular Chinese divination for the last several centuries. The coin method made the practice accessible to people whose situations did not allow for a two-hour ritual.

2. Portability

Yarrow stalks require a quiet table, the full set of 50 stalks, and a sequence of careful divisions that does not survive interruption. Coins fit in a pocket. The coin method survives the conditions under which most questions actually arise — at a difficult moment in a difficult day, when the question needs to be cast soon.

3. Remote readings

Most contemporary Liu Yao readings happen at distance. The questioner casts their own coins, records the six line values, and sends them to a reader. The reader then performs the reading on the casting that the questioner produced. This workflow only works because the coin method is simple enough that the questioner can perform it reliably with minimal instruction.

A yarrow stalk casting, sent at distance, would require either the questioner being trained in the method or the reader performing the casting on their own (which raises a different question: whose situation is being read?). The coin method's simplicity is what makes the questioner-casts model work.

Is one method "more accurate"?

This is the question most readers want answered, and the honest answer is: there is no evidence that one method produces "more accurate" readings than the other.

The accuracy of a Liu Yao reading depends on:

• The framing of the question — a poorly framed question produces a vague reading regardless of the casting method (see How to ask the I Ching a useful question)
• The reader's discipline in interpreting the casting
• The questioner's seriousness in bringing a real situation rather than a casual curiosity
• The honesty of the reading — not over-reading, not under-reading, not pretending to know what the hexagram does not show

None of these depend on whether the casting was done with coins or yarrow. The method generates the hexagram; the reading is what matters.

That said, the slight probability difference does have one structural consequence: a coin casting will, on average, produce slightly more changing lines than a yarrow casting. Some practitioners find this useful (more changing lines means more motion to read); others find it noisy (fewer changing lines means each one carries more weight). Both views are defensible.

The questioner-casts convention

A point worth naming explicitly: in contemporary Liu Yao practice, the questioner casts, not the reader.

This is sometimes surprising to Western readers who expect the diviner to do the casting. The convention in Liu Yao is the opposite: the questioner holds their question in mind, performs the coin throws themselves, records the six line values, and sends them to the reader. The reader then reads the casting that the questioner produced.

The reasoning is that the casting is part of the question itself — the random elements arise from the questioner's specific moment, their specific holding of the situation, their specific posture toward what they are asking. A reader casting on behalf of the questioner would, in this view, be reading their own moment rather than the questioner's.

Different schools handle this differently, but the questioner-casts convention is the standard in most Chinese Liu Yao practice today, and it is one of the reasons the coin method's accessibility matters: every questioner needs to be able to perform the casting reliably.

How Master Shen casts

Master Shen uses the three-coin method, and the questioner does the casting.

The procedure: hold the question in mind, take three coins of the same kind, toss them six times, and record each toss as a line value from the bottom up. The six values are then sent to Master Shen along with the question, and the reading is performed on that specific casting.

This is not a casting Master Shen performs for the questioner. It is the questioner's own casting, read with care.

If you have never cast before and want to bring a question, the only thing required is three coins, a quiet moment, and the question itself. The casting can be done in under a minute, and the reading then takes the form of a written response that walks through the hexagram, the trigram structure, the changing line, and the resulting hexagram in relation to what you have asked.

A note on what a Liu Yao reading is and isn't

A reading offers a structured reflection on the situation you bring to it. It is not a prediction of fixed outcomes, and is not a substitute for medical, legal, financial, or psychological advice. If you are facing a serious decision in any of these areas, please consult a licensed professional.

Further reading

• What is Liu Yao? The classical Chinese hexagram method — the foundation essay
• Liu Yao vs Wilhelm I Ching: A Side-by-Side — method comparison
• Reading the Changing Line: What Most Translations Miss — what the casting produces and why it matters
• From I Ching to Liu Yao: deepening your reading practice — for readers familiar with Wilhelm
• How to ask the I Ching a useful question — the question matters more than the casting method
• Hexagram 1 (乾 Qián / The Creative): A Liu Yao reading — what a casting looks like once it is read

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A reading on your situation

If you have a question and three coins, you have everything you need to bring a casting to Master Shen. Every first-time reader is welcome to a free opening reading — a brief personal note on what the hexagram is pointing to in your situation, with no payment and no obligation.