He then went back to France to live with his mother's parents, who worked in the Théâtre des Champs-Élysées and the Palais Garnier.
William left school at 16 to study composition with teacher Yves Margat (himself a student of Gabriel Fauré) and later harmony, fugue and counterpoint at the Paris conservatoire.
For example, some of his songs include carefully crafted orchestral passages (the Baroque introduction to Le nouveau monde) as well as instruments that are seldom found in pop music (such as a horn in Les miroirs dans la boue and a clarinet in Fier et fou de vous).
Additionally, he has also written film music (Titanic) and songs or arrangements for other artists (Dalida, Joe Dassin, Barbara...
[3][4] The "Introït" from his Lux aeterna (1972) was heavily sampled for the title track from Deltron 3030 (2000), produced by Dan the Automator.