From a Diary: I:xii

I'm not close to the work of Brian Eno, but the title of his essay Generating and Organizing Variety in the Arts did register strongly with me as a student. Programmaticaly alligned with British experimental music in the 70s, the essay's title zeroed in on what seemed (and still seems) to me to be a central contradiction — indeed a paradoxical relationship — around which music is necessarily made. We want a certain level of organization (order, coherence, "sense") but we also want enough variety (which necessarily breaks order, coherence, "sense") to sustain interest over the course of a piece. Now, we can radically break in the direction of either extreme, but human beings have a persistent capacity to find order in the face of disorder and surprise and variety in the ostensibly predictable and uneventful. The music of some composers (Cage and Young, for example) thrives in these boundaries, but in the wide middle territory between these extremes, the going gets more subtle, methinks. Jean Barraque's "proliferating series" for example, in which the order of pitch classes in one twelve-tone series is projected onto the succession of tones in a second series to generate a third will, in most cases*, generate a practically endless sequence of rows bearing no audible or intellectual resemblance in either intervallic profile or pitch sequence to the previously heard series. Working in such an environment of built-in, automatically-generated variety, the composer has to impose organization directly, drawing connections between the tones and intervals at the surface of the music that are not inherent in the material.

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* Off the top of my head, I suspect that one could feed two initial rows into the process with properties that guarantee a cyclical return to initial rows, probably after a very large number of iterations, but Barraque — like most Europeans, not informed by the concerns and forms of research going on in American twelve-tone theory — did not select for such a feature, requiring, instead, a practically unlimited variety of series. He certainly got that; any tonal coherence heard in his music is the direct result of the composer's asystematic intervention in the placement of tones in time, instrument, register, dynamic, and articulation.