The narrator interrupts the story to comment, judge, give an opinion, or speak directly to the reader.
In Don Quixote
he easily fitted everything he saw to his wild chivalries and ill-starred thoughts.
The narrator interrupts the scene to judge the hero's imagination with the adjectives "wild" and "ill-starred," and hands the reader the mechanism that explains all of the gentleman's visions.
I cannot make it out, nor can I persuade myself, that everything written in the previous chapter happened to the valiant Don Quixote exactly as written [...] and if this adventure seems apocryphal, I am not to blame; and so, without affirming it false or true, I write it down.
for me only Don Quixote was born, and I for him; he knew how to act and I how to write; only the two of us are made for each other, in spite of and to the chagrin of the feigned Tordesillas writer.
Part Two: The Defeat and Death, Cide Hamete Benengeli, to his pen, as he closes the book
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