There’s a technique known as “retrograde,” which would be reversing the series of notes in a melody or song.  Composers use this technique many times.  An example of a composer who used this technique would be Koji Kondo (the composer for famous video games, such as the Legend of Zelda, Super Mario, etc.).  A portion of his Ballad of the Goddess theme would be a retrograded portion of his Zelda’s Lullaby theme.  If utilizing this technique just resulted in meaningless, random, nonsensical, rubbi