In diatonic harmony
music, certain scale degrees
have an aural
tendency to "want to go" to other scale degrees.
The strongest tendency tone is the 7th scale degree or "leading tone
". It exhibits an unusually strong tendency to "go to" or resolve to the 1st scale degree, or "tonic
". This is why, in pop music
or church chorales
, when you hear a V7 chord it makes sense and even relaxes your ear when it goes back to the chord
the whole thing started in. 7 goes to 1, and your ear will always want to hear it go to 1, especially if it is sustained.
The other strong tendency in tonal music for 4 (subdominant
) to resolve down to 3 (mediant
). This happens often enough but not with the regularity that 7 moves to 1.
The major exception concerning the 7->1 movement is when the melody
descends from 1 in a conjunct
motion, 1->7->6->5, as in the first four notes of "Joy to the World