On making silent operas and how Einstein on the Beach was supposed to be about Hitler.

I began to make my first works for the theatre in the late 1960s, and they were all silent. This culminated in a major work that was seven hours long – and also silent. It was written with a 13-year-old African-American deaf-mute boy who had never been to school and knew no words. We were supposed to show it only twice in Paris in 1971 but it was a huge success and we ended up playing for five-and-a-half months to 2,200 people every night in a sold-out theatre. The last thing I had expected was to have a career in the theatre, as my background was in architecture and painting. The work was called Deafman Glance, and the French called it a “silent opera”. I started thinking about it and realised that’s exactly what it was: it was structured silences. That was my beginning.

Today if I’m directing The Ring of Wagner, Shakespeare’s King Lear or The Threepenny Opera, I still start directing the work silently. I know it will sound odd, but I’ve twice directed the Ring Cycle and each time I first...