Tao-teh-king. Part One: Tao: Chapter 11

1st ed. ELEVEN There are thirty spokes in a wheel, but its utility lies in the hole of the hub. The potter forms the clay into jars, but their usefulness depends upon the enclosed space. A carpenter builds the walls of a house and cuts out windows and doors, but the value of the house is measured by the space within the walls. Thus it may be said that existence is for accommodation but non-existence is for utility.