Xenakis’ Sieve Theory

Iannis Xenakis sternly criticized serial music in the mid-fifties. In response, he proposed and developed a set of compositional procedures which were mainly based on probabilistic laws that he framed under the principle of indeterminism. The sieve theory he developed in the sixties represented a return to deterministic strategies for composing. Following examination of Xenakis’ notes and sketches from the period spanning his time auditing Messiaen’s classes to his composition of Nomos Alpha, I argue that sieve theory is better understood when viewed through the lens of his personal earlier speculations on twelve-tone music techniques.