Many Zen pupils were studing meditation under the Zen master Sengai. One of them used to arise at night, climb over the temple wall, and go to town on a pleasure jaunt.
Sengai, inspecting the dormitory quarters, found this pupil missing one night and also discovered the high stool he had used to scale the well. Sengai removed the stool and stood there in its place.
When the wanderer returned, not knowing that Sengai was the stool, he put his feet on the master's head and jumped down into the grounds. Discovering what he had done, he was aghast.
Sengai said: "It is very chilly in the early morning. Do be careful not to catch cold yourself."
The pupil never went out at night again.