“How could such a large door be kept secret from everybody outside, apart from the dragon?" [Bilbo] asked. He was only a little hobbit you must remember.”
“A secret's worth depends on the people from whom it must be kept.”
“You do not steal from the dragon, oh, no. The dragon remembers.”
“It was the only secret I kept from her and eventually it became impossible to fix. With a secret like that, at some point the secret becomes irrelevant. The fact that you kept it does not.”
“Never laugh at live dragons, Bilbo you fool!”
“Secretly, deep down, everybody on Earth believes they can write poetry, apart from the members of the Poets' Guild, who know they can't.”