...the Force theme is most consistently developed and, consequently, most difficult to attach a specific meaning. This theme variously represents Obi-Wan Kenobi, the Jedi and the Force from which they draw their power, as well as more abstract ideas such as fate or destiny. In general, its appearances mark moments of significance in the films -- due in part to its portentous minor mode and upward-striving melody.
“Good relations with the Wookies, I have.”
--Yoda
