22.37Seventh chords make relative substitutions even clearer
Triads:
C and Am share 2 notes.
Sevenths:
Cmaj7 and Am7 share 3.
Likewise:
Fmaj7 and Dm7 share 3.
This is why jazz harmony can substitute them so fluidly.
Triads:
C and Am share 2 notes.
Sevenths:
Cmaj7 and Am7 share 3.
Likewise:
Fmaj7 and Dm7 share 3.
This is why jazz harmony can substitute them so fluidly.