“Metastaseis was inspired by the combination of an Einsteinian view of time and Xenakis’ memory of the sounds of warfare, and structured on mathematical ideas by Le Corbusier. Music usually consists of a set of sounds ordered in time; music played backwards is hardly recognizable. Messiaen’s similar observations led to his noted uses of non-retrogradable rhythms; Xenakis wished to reconcile the linear perception of music with a relativistic view of time. In warfare, as Xenakis knew it through his musical ear, no individual bullet being fired could be distinguished among the cacophony, but taken as a whole the sound of “gunfire” was clearly identifiable. The particular sequence of shots was unimportant: the individual guns could have fired in a completely different pattern from the way they actually did, but the sound produced would still have been the same. These ideas combined to form the basis of Metastaseis.”

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