Epigraphs are like little appetizers to the great entrée of a story. They illuminate important aspects of the story, and they get us headed in the right direction.
Nothing classes up a book like a Latin inscription, are we right?
Well, the epigraph to The Interpretation of Dreams is a line from Virgil's classical epic The Aeneid (Book VII: 312).
Freud's editor James Strachey translates it like this: "If I cannot bend the Higher Powers, I will move the Infernal Regions" (source). A more recent translation by Joyce Crick renders it a bit differently: "If Heaven I cannot bend, then Hell I will arouse" (source).
In The Aeneid, this line is spoken by Juno, jealous wife of head-honcho Jupiter. According to Crick, Freud didn't actually take it from The Aeneid directly but found it in "a political text by Ferdinand Lasalle"—the man who founded the German Social Democratic movement (source).
Whichever way you want to slice it, Strachey's editorial commentary in The Standard Edition shows us that Freud intended this expression of extraordinary determination to illustrate the power of our "repressed instinctual impulses" (source). How's that? Check out this passage from the final chapter of The Interpretation of Dreams, where Freud quotes the same line again:
In waking life the suppressed material in the mind is prevented from finding expression and is cut off from internal perception owing to the fact that the contradictions present in it are eliminated—one side being disposed of in favour of the other; but during the night, under the sway of an impetus towards the construction of compromises, this suppressed material finds methods and means of forcing its way into consciousness.Flectere si nequeo superos, Acheronta movebo.The interpretation of dreams is the royal road to a knowledge of the unconscious activities of the mind. (7.6.41-42)
We're telling you, Shmoopers: the next time you want to make one of your ideas sound AWESOME, throw a little Latin in there.