A definition of the series

Pierre Boulez attempting to define modern composition. I leave it to you to decide whether he’s achieved his end. (There’s a lot more, by the way, but this extract should suffice.)

The world of music today is a relative world, that is to say, one where structural relationships are not defined once and for all according to absolute criteria, but are organised instead according to varying schemata.
This world has arisen from the expansion of the idea of the series; that is why I should first like to establish a definition of the series from the strictest point of view, and then to infer from it an ensemble, a network of probabilities.
What is the series? The series is – in very general terms – the germ of a developing hierarchy based on certain psycho-physiological acoustical properties, and endowed with a greater or lesser selectivity, with a view to organising a FINITE ensemble of creative possibilities connected by predominant affinities, in relation to a given character; this ensemble of possibilities is deduced from an initial series by a FUNCTIONAL generative process (not simply the consecutive exposition of a certain number of objects, permutated according to restrictive numerical data).

Is it surprising, when you read this sort of thing (a) that Boulez’ own compositions are seldom heard? or (b) that the old tonal systems still continue their long-held sway?

From Boulez on Music Today, at the beginning of the third, and by far the longest of the three chapters, all of which continue on in this vein. Translated (I imagine with some difficulty) by Susan Bradshaw and Richard Rodney Bennett.