"Here all boundaries are weak, and the melody can be subdivided in countless ways, to permit multiple elaborations in the course of the aria. Yet it involves melodic thinking of the highest order. It is neither a theme nor a tune, but an unbroken melisma, which throws out spores around itself as it grows [italics mine]."But couldn't he also be describing Coltrane's Interstellar Space?
The melismatic vocal line that traveled from western Africa to the American blues (which most likely shares a common ancestor with Bach's) becomes permeated harmonically with the rise of jazz and is apotheosized in this last recording by Coltrane.
Here is another philosopher discussing Interstellar Space.