Yunmen Says It Upside Down (BCR15)

KOAN:

Then the student asked Yunmen, “But when it’s not the things I can see, and it’s not what the things are doing, what is it?”
Yunmen said, “Say it upside down.”

—Blue Cliff Record Case 15

ALSO,

KOAN: Yunmen Says It Backwards

Then the student asked Yunmen, “But when it’s not the things I can see, and it’s not what they’re doing, what is it?”
Yunmen said, “Say something backwards.”

—Blue Cliff Record Case 15 (transl. by John Tarrant & Joan Sutherland)