Lao Tzu : Tao Te Ching : A Book About the Way and the Power of the Way

by Lao Tzu

Clay is fashioned into vessels; but it is on their empty hollowness, that their use depends. The door and windows are cut out (from the walls) to form an apartment; but it is on the empty space (within), that its use depends.

The sage does not accumulate (for himself). The more that he expends for others, the more does he possess of his own; the more that he gives to others, the more does he have himself.