You all know that in the due course of time
If you continue scratching on a stone,
Little by little some image thereon
Will be engraven. Thus her friends went on
Comforting her so long, till in the end
She, with the help of hope and common sense,
Received the impress of their consolation,
Which loosened at long last her heavy sorrow:
She could not have endured such grief for ever.

-Chaucer, from "The Franklin's Tale" (trans. David Wright)