Diagnosis: Eight principles

Four axes, in this order

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The Eight Principles are four pairs, and the order you ask them in matters: first where it is, then what nature it has, then how strong it is. Yin and yang summarise the previous three.

Interior / Exterior

where it is

Cold / Heat

what nature

Deficiency / Excess

how strong

Yin / Yang

the summary of the three

Common mistake: Jumping straight to the organ without closing the four axes.

Sort each finding onto its axis.

• Clear, copious urineColdHeat
• Thirst for cold drinksColdHeat
• Better when wrapped upColdHeat
• Red tongueColdHeat
• Pale tongueColdHeat
• Scant, dark urineColdHeat

Heat that appears in the afternoon, with night sweats and a tongue without coating. How is it classified?

1. Interior · Heat · Excess
2. Interior · Heat · Deficiency
3. Exterior · Heat · Excess

The first axis locates, and that is why it comes first

Before asking what they have, you ask where it is. A picture at the surface gets released; one in the interior is treated at the organ. Confusing them sends the right treatment to the wrong place.

Aversion to cold with fever

it is at the surface

Superficial pulse

it is at the surface

Symptoms of a specific organ

it is in the interior

Months of history

it is in the interior

Common mistake: Tonifying while the factor is still outside: the fastest way to lock it in.

Sort each finding onto the axis that locates the problem.

• Aversion to cold that wrapping up does not fixExteriorInterior
• Months of abdominal painExteriorInterior
• Two days of a stiff neckExteriorInterior
• Persistently altered stoolsExteriorInterior
• Superficial pulseExteriorInterior
• Deep pulseExteriorInterior

Order the questions of the four axes.

1. Where is the problem?↑↓
2. What nature does it have?↑↓
3. How strong is it?↑↓
4. How does all that summarise?↑↓
5. Which organ is involved?↑↓

Flushed face and a sensation of heat, but wants to cover up, drinks hot and has a deep, weak pulse. What is it?

1. Real heat: the face confirms it
2. Heat and cold mixed in equal parts
3. Real cold with the appearance of heat

Match each axis with the question it answers.

Years of cold in the back, clear urine and a deep, slow pulse. Build the classification.

Alternating chills and fever, bitter taste and no appetite, one week in. Where is it?

1. Clearly at the surface
2. Halfway: neither fully outside nor fully inside
3. Clearly deep in the interior

Sort each finding onto the strength axis.

• Weak pulse that scatters under pressureDeficiencyExcess
• Full pulse pushing back at the fingerDeficiencyExcess
• Faint voice and short breathDeficiencyExcess
• Loud voice and noisy breathingDeficiencyExcess
• Pain that welcomes pressureDeficiencyExcess
• Distension that refuses pressureDeficiencyExcess

A picture classified as Interior · Cold · Deficiency. What summary does it get?

1. A yin pattern
2. A yang pattern
3. It cannot be summarised: the three axes are independent

Cold extremities and, at the same time, burning stomach with thirst. Impossible?

1. Yes: cold and heat exclude each other
2. Yes: one of the two symptoms was recorded wrong
3. No: there can be cold below and heat above at once

Match each picture with its classification.

Why do the Eight Principles come before any other diagnostic method?

1. Because they are the oldest
2. Because they close the decisions that condition everything else: where, what and how much
3. Because they are the easiest to apply