Suwen · On the Channels and Collaterals

The text

The Yellow Emperor asked: When the collateral vessels appear, their five colors are each unlike — green, yellow, red, white, and black are not the same. What is the reason? Qi Bo answered: The channels have a constant color; the collaterals have no constant, and they change. The Emperor said: What is the constant color of the channels? Qi Bo said: The heart is red, the lung white, the liver green, the spleen yellow, the kidney black — all also answer to the color of their channel vessels. The Emperor said: The yin and yang of the collaterals — do they also answer to their channels? Qi Bo said: The color of the yin collaterals answers to their channels. The color of the yang collaterals changes without constant; it follows the four seasons and travels. When cold is much, they congeal and weep; when they congeal and weep, they are green-black. When heat is much, they are moist and glossy; when moist and glossy, they are yellow-red. These are all constant colors, and are called no illness. When the five colors all appear, it is called cold and heat. The Emperor said: Good.

The line

Qi Bo answered: The channels have a constant color; the collaterals have no constant, and they change.

The note

The channels have a constant color; the collaterals have no constant, and they change. The collaterals are the messengers of the channels. To see the color of a collateral is to see what the channel has not yet had time to say.