A vessel is formed from a lump of clay with care, however, it is the empty space within the vessel that makes it useful.
LaoziThe great Way is all-pervading. It reaches to the left and to the right. All things depend on it with their existence. Still it demands no obedience.
LaoziIn ancient times, those who followed the Way did not try to give people knowledge thereof, but kept them ignorant.
Laozi