Right when the episode opens, the music sounds very similar to John Williams' "The Planet Krypton" track from Superman : The Movie soundtrack
The title of this episode is a reference to a phrase coined by British philosopher Gilbert Ryle to describe René Descartes' concept of mind/body dualism. It is meant to describe how a spiritual mind or consciousness (the "ghost") can occupy and somehow control a physical, mechanical body (the "machine"). The phrase has since been frequently used to describe Artificial Intelligence in computers.