Answer:
The man who invented it doesn't want it. The man who bought it doesn't need it. The man who needs it doesn't know it. What is it?
What flares up and does a lot of good, and when it dies is just a piece of wood?
He has married many women but has never married.
A harvest sown and reaped on the same day in an unplowed field. Which increases without growing, remains whole though it is eaten within and without. Is useless and yet the staple of nations.
What weaves webs as they grow?
Bury deep, Pile on stones, My mind will always Dig up them bones