Sospeso's tribute concert to this extraordinary composer was on October 19, 2001. 

Xenakis was born into a prosperous Greek family in Braïla, a Romanian city on the Danube delta opening into the Black Sea, in 1922. His father was a shipping merchant and represented a British trading company in Romania. Xenakis's mother died when he was five, and he was placed under the supervision of a series of governesses, from whom he learned English, German, and French; he attended a Romanian school and was privately schooled in Greek. In 1932 the child was enrolled in an international boarding school on the island of Spetses, in the Saronic Gulf, Anargyrios & Korgialenios College, the elite boys academy in Greece, based on the British model (the author John Fowles taught there in the fifties). Xenakis avidly read French, English, and classical Greek literature, and the English headmaster (who secretly worked for British Intelligence) introduced him to classical music. Soon he was drawn to mathematics, and his next move was to Athens, to follow a two-year preparatory course for the Athens Polytechnic engineering department. There he began to pursue music more seriously, with piano lessons and studies in theory and counterpoint, although contemporary music remained unknown to him. He passed the Polytechnic entrance exam in 1940, but his studies were effectively suspended when Mussolini crossed the Albanian border.

Various Greek resistance groups sprang up immediately, covering a wide political spectrum; this perhaps reflected the contradictions of the Greek dictator Ioannis Metaxas (the former prime minister who had dissolved the constitution), who was an essentially fascist leader that strove to strengthen his country's alliance with Britain. Indeed, when Xenakis first entered the resistance, he joined a right-wing group. But by the time the Germans forced the allies out of Athens, he had turned to Communism.

Xenakis's participation in the Greek resistance was a formative event in his life. He participated in and helped organize mass demonstrations that sometimes turned violent. The Greek left-wing resistance was among the most successful in Europe: Greece was the only German-occupied country that thwarted Hitler's attempts at imposing forced labor. Xenakis also had a musician friend in the resistance who introduced him to contemporary music—Debussy, Ravel, and Bartók—for the first time.

Italy capitulated in 1943, and the Germans evacuated a year later; the Balkan Pact between England and Russia gave Greece to England's sphere of influence. Ironically, the British hostility towards the Greek left resulted in new strife between British troops (who occupied the Pantheon—'even the Germans did not dare that,' Xenakis noted) and the left-wing student battalions, one of which Xenakis was by now leading. It was during a fight in December, 1944, with British troops—not with the Germans, as many believe—that Xenakis was nearly killed by a mortar explosion, permanently disfiguring the left side of his face, blinding him in one eye.

Xenakis completed his engineering degree in 1946, but his continued political engagement-inflamed by the British and American support of the exiled Greek right-wing government, by the virtual capitulation of the Greek left, and by British rule in Cyprus-resulted in imprisonment. The compulsory draft finally drove him underground. Desertion was punishable by death, so in 1947, with the help of Greek and Italian communists, he escaped to Paris through Italy with a forged passport. (His Greek death sentence was lightened in 1951 to ten years' imprisonment, but this sentence was not revoked until 1974.)

Originally, his plan was to continue to America to study engineering; his brother was studying philosophy there. But he benefited from the political power of the Communist Party in France and was found an engineering position in the large atelier of the celebrated Swiss architect Le Corbusier (Charles-Édouard Jeanneret). His first project there was one of Le Corbusier's largest and most important, the housing complex, or unité d'habitation, in Marseille, a vertical community harboring more than 1800 people. At this point Xenakis disliked what little of modern architecture he knew, but he stayed with Le Corbusier, and gradually he began to find it simulating; Le Corbusier in turn began giving him more responsibility. The modernist purism of Le Corbusier's architectural thought, the emphasis on bold designs constructed from geometric volumes, certainly has parallels with his own musical thought, still in development. Paris became more permanent for him upon meeting his future wife, Françoise, and he was to live there for the rest of his life.

Meanwhile, he was pursuing music, writing music surreptitiously at his desk at work; still self-conscious of his relative lack of musical training, and totally unfamiliar with the Parisian musical world, he pursued and rejected a series of teachers. He had a disastrous lesson with Honegger, and studies with Milhaud were not much better. Boulanger told him he was too old to start lessons. It was Le Corbusier that pointed Xenakis in the direction of Varèse and Messiaen. When he worked up the nerve to approach Messiaen, the great composer had some surprising advice: to forsake the study of harmony and counterpoint in favor of his instincts and his gifts in mathematics and architecture.

With Messiaen's encouragement Xenakis was able to write with confidence for the first time. One of the first works he composed after starting Messiaen's course at the Paris Conservatory in 1952 was the original version of Zyia, for soprano, flute, piano, and male chorus. Zyia is a rare example of his student music, one of the few works from this time he allowed to be published. Its suggestion of folk music may reflect the gypsy music he heard as a youth in Romania, or the Greek folk music of Spetses. The modernism, however, is wholly individual, owing nothing to French modernism before Messiaen nor the expressionism of the Second Viennese School. 'My great passion,' he wrote that year, 'is a marriage between Western music and the folk music of my own country.'

In the fifties, his music began receiving performances and minor awards; meanwhile he was promoted at Le Corbusier's firm from engineer to architect, collaborating on the design of the Couvent de la Tourette. In 1958 he helped design the revolutionary Philips Pavilion for the Brussels World's Fair, a concrete building created entirely of curves. Le Corbusier and Xenakis argued over credit for its design; this was one of the tensions that resulted in Xenakis's dismissal from the firm a year later. From this point he worked as a free-lance engineer, but as little as possible, in order to devote himself to composing, which was rapidly overtaking architecture as his primacy medium; and his music began to be widely appreciated. Architecture continued to inform his creativity, however; or more precisely, it was mathematics that gave Xenakis the unified means to design both compositions of volume in space (architecture) and of sound in time (music). The breakthrough orchestral work Metastaseis was born of a conception of time as a representation of physical space, and musical material as a representation of matter whose behavior is governed by forces, applications of energy, expressed by formulae that are applied to the music much as a scientist might graph a function, or an architect a shape. In this way, Xenakis's composition owed less to the history of Western music than that of any other composer, and yet, in its total disregard for the conventions of beauty in favor of depicting powerful forms, it spoke with a stunning emotional energy. Hans Rosbaud conducted the premiere of Metastaseis (along with an entirely different breakthrough work, Boulez's Le Marteau sans maître) at the 1955 Donaueschingen Festival, and it caused a sensation. But however provocative, Xenakis's music should not be understood as simply rebellious; commentators should be careful in drawing analogies between his history of political resistance and his artistic independence. His brief critique of mainstream European modernism that he wrote that year, The Crisis of Serial Music, is less a denunciation than a manifesto expressing an entirely different—and to an extent, incomparable—aesthetic orientation.

Xenakis's work was subsequently championed in Europe by the conductor Hermann Scherchen, in Japan by the pianist Yoji Takahashi and the composer Toru Takemitsu. Xenakis articulated his aesthetic theory in his 1963 book Formalized Music, where he uses the term 'stochastic' to describe a music of sound masses, whose activity over time is controlled by a combination of determinacy and randomness. 'In fact,' he wrote, 'sonic discourse is nothing but the perpetual fluctuations of entropy in all its forms.'

Xenakis's inclination towards pure form, imagined with the precision of a scientist, led him to the realms of electronic and computer music. Both were in their infancies around 1960, and Xenakis did much to develop them. Messiaen had introduced him to Pierre Schaeffer, the proponent of musique concrète, electronic music that primarily used sounds recorded from real life without sonic manipulation. Xenakis, however, was fascinated by the creation of sounds from scratch, as it were: electronically designing waveforms to modulate other waveforms, thus producing complex sounds. The numbers of the formulae describing these processes are converted to sound through a digital to analogue converter. As in 1961 there was only one computer with the power and design to perform this type of sound synthesis—at Bell Labs in the United States—Xenakis must be among the first artists to have both creatively and technically grasped a central axiom of the post-industrial age, that the digital revolution provides a perfectly transparent means of translating material from one medium to another. From the beginning, Xenakis refused to acknowledge barriers between music and architecture, and indeed stylistic elements that he considered barriers were ruthlessly stripped away. In 1962 he used a computer to design an acoustic work for forty-eight musicians entitled ST/48-1.240162. In 1977 he opened a research institute devoted to electro-acoustic and computer music, UPIC, in Paris.

During the 1960s and 1970s Xenakis saw international recognition: Copland invited him to Tanglewood in 1963; there were important invitations to Venice, Berlin, Bloomington, Iran, Israel; there were performances by Pierre Boulez, Lukas Foss, Leonard Bernstein, Zubin Mehta, Seiji Ozawa, and Peter Eötvös. Three of the works on Sospeso's program date from this period. N'Shima was premiered in Jerusalem in 1976. The title is Hebrew for 'breath, air, spirit,' and the rabbinical text is divided into separate syllables before being treated abstractly, producing a vivid, fierce, imaginary folk music. Dmaathen, for oboe and percussion, was written in the same year, and the ensemble work Palimpsest was written in 1979 for the Italian Divertimento Ensemble.

Thalleïn (Greek for 'burgeonning') was written in 1984 for the London Sinfonietta. One senses in this relatively late work a more direct approach to musical convention, as well as a certain opulence; Cécile Gilly hears in the piece 'a distant reminiscence of the Rite of Spring.' And the latest work by Xenakis on Sospeso's program is also the earliest: a new version of Zyia, written under Messiaen, that he revised for our concert's flutist, Cécile Daroux, in 1994.

Xenakis died in Paris on February 4, 2001, aged 78. Ivan Hewett wrote in the Guardian that Xenakis's music, 'such magnificently innocent music, is bound to be out of place in our oblique, knowing age, so obsessed with its past, so fastidiously ironic, so concerned, in its art, to layer ambiguity upon ambiguity.' Indeed, it is difficult to think of another composer whose passion is so entirely devoted to the future; it is this generosity that is his legacy.

Joshua Cody