Mold clay into a vessel;
It is the emptiness within that creates the usefulness of the vessel.
Cut out doors and windows in a house;
It is the empty space inside that creates the usefulness of the house.
Thus, what we have may be something substantial,
But its usefulness lies in the unoccupied, empty space.
The substance of your body is enlivened
By maintaining the part of you that is unoccupied.