(From the
Appendix
to ORIGIN OF MUSIC, 3rd ed., by BOB FINK
1980)
As ancient musicians developed the scale & melody
a sense of "key" or "tonality" also developed. (Formerly
ancient musicians paid more attention to the beauties of single tones,
gongs, etc., without much sense of notes being "connected" into
melodies.)
Early attempts at harmony, such as drones (used in
Scottish
or other bagpipes, or as one of the two "double flutes" in ancient
Greece, for example), could have been an attempt to make a sense of
"keynote"
more audible. The accidental harmonies (and dissonances) resulting from
this were a step beyond the earliest harmonies formed by singing the same
chant or melody an octave apart (or at 5ths apart called "organum").
In organum, the voices all move up or down to conform to the single melody.
With a drone, however, one voice carries a melody
independently
of the drone accompaniment. It is not hard to expect that some modifications
of the drone (making it, historically speaking, become more of a melody
unto itself) paved the way to early "counterpoint," which is
the singing or combining of separate independent melodies rather than combining
the same melody at different pitches to suit different voice ranges as
in organum.
Melodies were the most important feature for early
musicians,
and so they were able to accept the mix of the accidental harmonies and
discords formed by the separate melodies, so long as it all created a tolerable
whole.
The centuries-long fascination of musicians with this
counterpoint eventually led to the discovery of separate chords which were
abstracted from the spontaneous harmonies formed by the criss-crossing
melodies within the counterpoint. Later, the modern concept of simply adding
chords to harmonize a single melody was developed.
None of this could have occurred until scales & the
concept of melody (and a sense of key or tonality, which connects notes
to make them into melody) had fully evolved. Now that the earliest song
places the diatonic scale much earlier in history, many of the early forms
of harmony become more explicable.
