National museum in Athens mounts major retrospective for pioneer of avant-garde music and apprentice to Le Corbusier who was sentenced to death by the military

He was the high priest of 20th-century modernity, a founding father of electronic music, a pioneer of multi-faceted talent. Where others feared to tread Iannis Xenakis stepped, breaking the boundaries of sound, employing mathematical formulae – game theory included – to compose what had never been heard before.

No musician – or architect, for he was that too – was as steeped in the classics nor as avant garde nor as quintessentially Greek.