Zen Master Seung Sahn, the first Korean Zen master to spread Zen Buddhism in the West:
“Deep in the mountains, the great temple bell is struck. You hear it reverberating in the morning air, and all thoughts disappear from your mind. There is nothing that is you; there is nothing that is not you. There is only the sound of the bell, filling the whole universe. This is Zen mind.
“Springtime comes. You see the flowers blossoming, the butterflies flitting about; you hear the birds singing, you breathe in the warm weather. And your mind is only springtime. It is nothing at all.
“You visit Niagara and take a boat to the bottom of the falls. The downpouring of the water is in front of you and around you and inside you, and suddenly you are shouting: YAAAAAA!
“In all these experiences, outside and inside have become one. This is Zen mind. Your mind is clear like space.
“Clear like space means clear like a mirror. When white comes, white. When red comes, red.
“But one more step is necessary. How does your mind function in everyday life? When somebody is hungry, just reflecting hunger is not enough. You have to give him food! This is called correct situation, correct relationship and correct function.
“This means that you can respond to every situation in a compassionate way.”