The works Eco gives as examples are interesting because they eschew the traditional regions of uncertainty (as Empson might have described them if he were looking at music and not poetry). They are not so much ambiguous by design — as most works are — but are ambiguous through abdication of authority. To put it another way, the ambiguity effect in these pieces does not conceal any particular intent; instead, the effect is the intent. Interestingly, this did not necessarily preclude a composer from expressing detailed instructions to a performer toward the end of making an authoritative recording (Cynthia Folio & Alexander R. Brinkman, "Rhythm and Timing in the Two Version of Berio's Sequenza I for Flute Solo", 3-5). This sort of tinkering seems to undermine any sort of symbolic function that might be said to be at work; there is a fine line, it seems, between symbols of infinity and symbols of nothing at all. But we have taken a step or two back from the nihilistic abyss since the middle of the twentieth century and it is not surprising that composers nowadays who employ planned indeterminacy for the most part do so within the context of a broader design and use it as a tool, a color, or means to an end rather than an end in itself. Our times are not so desperate that structure need replace concept.

Troublingly, in a single parenthetical statement at the outset of his text, Eco notes that openness has always been commonplace in traditional music — at which point, he resumes ignoring traditional music altogether (Ibid. 1-15). Of course there is a difference between any tradition of musicians organically riffing by ear on a melody or rhythm, and the Western tradition of written music's experiments with indeterminacy. And yet. There is a tangible feeling of the latter's being a sort of forced version of what the former does naturally. It is literally forced in the sense that it is prescribed with a set of denoted instructions, even if those instructions are as open-ended as "play whatever you want." Prescribed ambiguity might more aptly have been characterized as a retreat or a return to something fundamental, rather than an advance, if indeed we are required to swallow this notion of linear progress in the arts in the first place. There is a faint, but detectable, stench of elitism here in the congratulating of an academic class for a breakthrough in something that has already been intrinsically understood and practiced for centuries by nearly every type of non-strictly-"classical" musician. Eco is hardly alone in committing that transgression, and I'm not alone in noting it:

The historiography of art — and particularly, it seems, of music — remains the most stubbornly Whiggish of all historiographies, despite longstanding maverick opposition. That historiography is still a Tradition-of-the-New narrative that celebrates technical innovation, viewed as progress within a narrowly circumscribed aesthetic domain. (Richard Taruskin, "A Myth of the Twentieth Century: The Rite of Spring, the Tradition of the New, and 'The Music Itself'")

Thankfully, artists are not limited to the temporal plane when seeking inspiration for their work. Critics are reared and steeped in this plane, perhaps because it is among the easiest to map, however misguided a tendency toward quixotic and