Plain n simple this man let his very soul speak through the double bass Mysterious, semi-dark, and has this Spacey type feel like floating in the empty void letting the DB's voice sing for you with NO thought put into it....letting it come naturally
Rufus lets his bass play music. He doesn't try to impress anyone with how many notes are on his bass and doesn't try to play as though he was being paid by how many notes he can play.
I believe he meant two notes occurring at the same time in relationship to each other. Simplicity of a single line melody over a seemingly stagnant undertone.