The above exchange took place amongst Zen monks in the eighth century and is the first reference to Zen circle art or enso. Enso is a quick circular brushstroke of black ink on rice paper that forms a circle. It is said to have such a meaning that to express it in words is impossible.
The gye yal (Eng. Brushstroke) is a form of Zen circle art. It is the spontaneous circle mark found on the inside or out of a tea bowl. It embodies the same 'no mind' that the black ink of a calligraphers' enso has come to represent.
Contemplating the gye yal is to look deeply into nothingness.
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What is this???
Peace