In fiction, a quibble is a plot device used to fulfill the exact verbal conditions of an agreement in order to avoid the intended meaning.
He feels safe since he knows that forests cannot move, but is overcome when the English army, shielded with boughs cut from Birnam Wood to hide their numbers, advances on his stronghold at Dunsinane.
When the hero of the Child ballad, The Lord of Lorn and the False Steward, is forced to trade places with an impostor and swear never to reveal the truth to anyone, he tells his story to a horse while he knows that the heroine is eavesdropping.
In the similar fairy tale, The Goose Girl, the princess pours out her story to an iron stove, unaware that the king is listening.
In Terry Pratchett's Moving Pictures, a book is said to inflict terrible fates on any man opening it, but causes only mild annoyance to the Librarian, who is in fact an orangutan.