Look, and it can’t be seen.
Listen, and it can’t be heard.
Reach, and it can’t be grasped.
Above, it isn’t bright.
Below, it isn’t dark.
it returns to the realm of nothing.
Form that includes all forms,
image without an image,
subtle, beyond all conception.
Approach it, and there is no beginning;
follow it, and there is no end.
You can’t know it,
but you can be it,
at ease in your own life.
Just realize where you come from;
this is the essence of wisdom.
-Lao-tzu- (Tao Te Ching, verse 14, interpretation by Stephen Mitchell)