Have you heard of the mood of the 5th?
I am just so mesmerized by the whole theory behind it
the music is sung in a way that it has a center point and it makes a figure eight around the center note. SO if you start on A the note will got up and come back down to A and then go down and come back up to A again. 8
like amazing grace is a pentatonic song sung in the mood of the 5th and so is old man river.
The below info is from wiki
A pentatonic scale is a musical scale with five pitches per octave in contrast to an heptatonic (seven note) scale such as the major scale. Pentatonic scales are very common and are found all over the world, including but not limited to Celtic folk music, West African music, African-American spirituals, American blues music and rock music, Sami joik singing, children's songs,