The half-century journey from Boulez's Flute Sonatina to Berio's Ofanim is a journey not just from one time to another but from one kind of time to another. To Boulez in the 1940s, time was a railway track, and the composer's duty was to be on the train, preferably driving the engine. The view to the sides was irrelevant. Shostakovich, Britten, Poulenc, Copland, Dallapiccola: such other voices of the 1940s could not be heard by those on the history express. Even Stravinsky and Schoenberg could not be heard.
But though it may be hard still to sympathize with the young enthusiast's intolerance and ungenerousness, there was something brave and inspiriting about the late modernist adventure. Otherwise it could hardly have commanded such widespread attention and support, nor could it have resulted in works which took music to the edges of the possible so quickly and in so many different directions: Le marteau sans maiître, Gruppen, the Barraqué Sonata, Tempi concertati, Movements, 4' 33", Partitions, Oiseaux exotiques, and Il canto sospeso make an extraordinary bunch of works to have come out of one decade, the 1950s. The changes they brought cannot be unsaid. Even the splitting of time -- for now we look back not along one pair of ever parallel rails but into a tangle of ribbons blowing behind us and constantly changing in what they reveal of themselves (what they reveal, therefore, of us) -- even this splitting into so many simultaneous histories was implicit in the 1950s, in the divergences among the works just mentioned.
It was in the early 1960s, though, that the idea of a single way forward became untenable, even as music acquired again qualities of richness and diversity: this was the time of Chronochromie, of La mort de Virgile, of Kontakte, of Epifanie, of Pli selon pli. And towards the end of the 1960s composers began to took seriously at what 'progress' had left out of account: harmonic continuity, pulse, expressive gesture, theatre, the past. Hence Requiem Canticles. Hence Sinfonia. Hence Punch and Judy. Hence Hymnen. Hence Die Soldaten. And hence the vitality of early minimalism.
Yet after those few years of hope and chaos, at the end of the 1960s and into the early 1970s, music entered a relatively barren period -- a period, perhaps, of exhaustion, and of confusion caused by the absence of any generally agreed aim or aesthetic. The doubtfulness of that time was, I think, reflected in the first version of this book, which is one reason why a thorough-going revision was necessary, because now the atmosphere is very different. What happened in the mid-1980s was quite extraordinary: The Mask of Orpheus and Earth Dances, Un re in ascolto and Formazioni, Saint FranÇois d'Assise, the Kafka-Fragmente, the Carceri d'invenzione, Prometeo, Nixon in China, the late works of Feldman and Cage. As to the reason --