Webb appropriated the title from the 1966 science fiction novel The Moon Is a Harsh Mistress by Robert A.
The third verse modulates three half steps (from G to B♭), with the rhyme scheme altered to ABABCDC, and the coda repeating the DC.
I was reading Ray Bradbury and Isaac Asimov and learning a great deal about the patois of the language itself and how these words were being used to create emotions.
[1] Since Joe Cocker's first recording of the song in 1974, "The Moon Is a Harsh Mistress" has been recorded by a variety of artists, from traditional renditions by female singers such as Judy Collins, Linda Ronstadt, and Joan Baez, to versions by male singers such as Glen Campbell, and Michael Feinstein.
[3] Various instrumental versions have also been recorded, including the 1997 version by Charlie Haden and Pat Metheny on the album Beyond the Missouri Sky (Short Stories), which won a Grammy for Best Jazz Instrumental Album, Individual or Group.