I bet a guy came out of a police box and gave them the ideas....
I was interested to discover that the wonderful scene in Amadeus where Mozart has the dancers in The Marriage of Figaro dance without music (because Count Orsini-Rosenberg had torn the section out of the sore, claiming that the Emperor had banned ballets) was based on an actual occurrence (though in fact there is no evidence that the Emperor had done any such thing).
The other matter of contention was that of the dance used during the third act. There is evidence that Count Orsini-Rosenberg did in fact tear the scene from the music claiming that “the Emperor won’t have ballets in his theatres,” as is portrayed in the movie. Interestingly though, no real edict has ever surfaced in which Emperor Joseph banned ballet. Confusion remains as to the source of Rosenberg’s statement, but in the end dancers were hired, and the scene was performed. Though the movie scene was based on historical events, Cathleen Myers points out that in the film, the dance is set to the wrong music. She says: “Mozart provided actual dance music (the Fandango adapted from Gluck’s ballet Don Juan) for the wedding dance; it was [not] danced to the Third Act March.
I can't find a clip of the scene, but we see the Emperor dropping in on a rehearsal and seeing folk dancing to no other sound than their own feet. "I don't understand", he says, "Is it modern?"
Not only modern but prescient, because by subtracting just the music and leaving every other element in place Mozart was forcing his audience (albeit only for the rehearsal - the music was reinstated at the Emperor's command) to attend to all the other sounds going on which would normally be covered up by the music. Which of course is exactly what John Cage did with his "silent" (or more accurately "un-played") piano piece 4'33", where you hear only the ambient noise of the hall, the audience and of course the pianist himself.
Another example of a musical work ahead of its time is Gilbert and Sullivan's The Gondoliers, though in this instance it's Gilbert's libretto which makes the leap. In the operetta there are two gondoliers (Marco and Giuseppe), one of whom is the rightful king of Barataria. It is impossible to tell which one is the king until their foster-mother can be located, so in the meantime they share the kingly duties and privileges fifty-fifty. This provides a terrific example of the Schrödinger's Cat paradox from quantum mechanics: Marco and Giuseppe each has a king function of 0.5 and behave in all respects as though they were equally kingly, in just the same way as the unfortunate cat has a 50% probability of life and 50% of death. Once the king's identity is revealed, one will have a king function of 1 and one a king function of 0, just as the cat turns out to be alive or dead when its box is opened. This provides a pretty good example by which to explain the cat business, I have found, despite the operetta's having been written in 1889 while Schrödinger only came up with his idea in 1935. Even the basic idea of quantum theory was not formulated until 1900. Of course, in the operatta it turns out neither of them is in fact king: the box is opened and the cat is missing.