Eihei Dogen Zenji once said to his assembly:
A dragon howls in a dark cave; the whole universe quiets. A tiger roars at the edge of a cliff; the cold valley becomes warm. Kaa!”

This is what you have been hearing all along, even if you don’t realize it. You hear it when the wind blows through the trees or when you set a spoon down on the table. But to hear it right, you have to become a dragon or a tiger.
How do you do that? How do you become a dragon or a tiger? It’s all well and good to answer, “Let go!” or “Sit!” or “Practice zazen!” But if you sit in zazen that is just the cave; if you let go, that is just the edge of a cliff. Where is the dragon, where the tiger? How do you hear the howl at the center of the universe, the roar beyond life and death?

Sometimes, as I take a step when walking in kinhin, I disappear. But the stepping is still there. Seated in zazen, the cushion is all by itself, but breathing still happens. If you want to penetrate into this, you will have to be alone. I do not mean that you need to be solitary. To be alone means to apprise yourself of your immaculate nature. To apprise yourself of your immaculate nature, leave off dragons and tigers entirely. Do not make something up about sun-warmed valleys or the quiet of interstellar space.
Just go on toward it and, without howling or roaring, tell me: what is the sound of your whole life?
I like yer thinkin’, Woody.
“There’s a snake in my boot!”