The reader or audience knows something the character ignores, and so the character's words and actions take on a meaning he does not perceive himself.
In Madame Bovary
She did not believe that things could present themselves in the same way in different places, and, since the part already lived had been bad, the part left for her to live would surely be better.
Emma concludes that the part of her life that remains "would surely be better." The reader, who has seen the convent, Tostes and the ball solve nothing, perceives the illusion of someone who thinks that changing place changes what makes her suffer.
Part II, Chapter 2, the narrator
Come on, tell us something…, Adolphe…, Dodolphe… I think.
Part III, Chapter 3, the boatman, repeating what the revelers said to the tall man
lessons [...] are only worthwhile if they are followed
It was fate's fault!
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