Taruskin offers an alternative: music had an oral pre-history; that music that preceded the development of notation (such as the chant we have been discussing lately). Oral, that is non-notation based, music has continued to exist alongside notated, or literate music, ever since. Recently, with the growth of non-notated popular music as a huge presence, we seem to be moving into a post-literate stage. Paul McCartney, the richest composer/performer in all of music history, claims to have never learned to read music. This was partly made possible by the development of sophisticated recording technology. The Beatles composed in the studio with the aid of sound technology.
My own career in music reflects these shifts. My mother was a folk musician who did not read music, who played "by ear". For the first three or four years I did the same. But when I discovered classical music, I converted myself from a pre-literate musician into a literate one. I was moving in the wrong direction, of course, as viewed in retrospect, the musical world was moving in the opposite direction!
This has been rather abstract, so let me offer some examples. Here is some pre-literate music. First the African mbira or thumb piano, from Zimbabwe:
Haec Dies an Easter gradual that was probably 'composed' before notation was developed:
A tune by the Beatles that was partly composed at the guitar, lyrics written on a napkin, and finished in the studio. When 'literate' musicians were invited in to play solos, such as perhaps the flute-player here, George Martin stepped in to write out the parts.
Literate music often made use of the style of pre-literate music such as this Occitan dance-song from the 12th century. The notation used for this was the same as for chant, i.e. rhythms not clearly specified so everything you hear in this arrangement that is rhythmic, such as the percussion and the note-values, was added by the performers:
I'm sure you are very familiar with examples of 'literate' music, but here are a couple just as reminders. First, a Haydn quartet movement influenced by pre-literate gypsy music:
The great symphonic works of the 19th century would not have been possible without the resources of notation:
Music literacy leads to the possibility of much greater complexity, that is not possible if everyone is playing by ear such as in this composition by Berio that quotes from many sources including a Mahler symphonic movement:
Alongside the 'literate' music, the non-literate or oral tradition, was still always present. Jazz musicians occupy a kind of middle ground in that they are nearly all literate musicians, but a great deal of what they play is, intentionally, not written down:
Right now, there are so many technological resources, such as synthesizers, drum machines, sequencers and digital recording, that the ability to write down music seems to many to be of very little use. Plus, the notation we have is poorly adapted to record the kind of music that is now possible. Here is an electronic piece by Stockhausen using both synthesized and recorded sounds:
In my own composition I suppose I am an anachronism as I write everything down, or try to!