Dao De Jing chapter 11: thirty spokes converge on a hub, but it is the empty center that makes the wheel useful; clay is shaped into a vessel, but it is the hollowness that makes it useful; doors and windows are cut out to make a room, and it is the empty space that makes it useful. 'Therefore, being provides the benefit; nonbeing provides the use.' The Guodian slips confirm the chapter's antiquity.
The chapter is routinely quoted in defense of decluttering and empty calendars, a lifestyle aesthetic. The text is not advising less stuff; it is locating function in absence, a claim about ontology, not interior design.
Read with chapters 1 and 40, emptiness is not a lack but the active ingredient: the nameless, the hollow, and the return are one principle. The chapter is the Dao De Jing's engineering diagram of wu, nonbeing, doing all the actual work.
If usefulness lives in the empty part, what are you filling your life with?