“An author…may wish to include an epigraph — a quotation that is pertinent but not integral to the text”*…

Epigraph: To Kill A Mockingbird, Harper Lee

Epigraph: Slaughterhouse-Five, Kurt Vonnegut
Examples from Phoebe Pan‘s “ongoing collection of epigraphs.”
* Chicago Manual of Style
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As we appreciate appositeness, we might send silly birthday greetings to Edward Lear; he was born on this date in 1812. An artist, illustrator, musician, author, and poet, he is known now mostly for his literary nonsense in poetry and prose– including his limericks, a form he he did much to popularize.
They dined on mince, and slices of quince
- Which they ate with a runcible spoon;
And hand in hand, on the edge of the sand,
- They danced by the light of the moon,
- The moon,
- The moon,
They danced by the light of the moon.
-“The Owl and the Pussycat” (probably Lear’s best-known poem)