On the use of music in Kubrick's films and why it is different from conventional scoring.

Kubrick did not use original scores for most of his major films. He used pre-existing classical and contemporary music, and his choices were rarely obvious: not the pieces you would expect, placed in ways you would not predict.

The 2001 opening — Also Sprach Zarathustra — has been parodied so many times that its original effect is almost impossible to recover. But the choice is precise: the piece represents human aspiration, the reaching toward a higher form, which is exactly the film's subject. Kubrick understood that the piece had accumulated a cultural weight that he could use and then subvert.

The waltz sequences in the space station section — using The Blue Danube — are one of cinema's great tonal coups: the weightlessness of spaceflight rendered as the weightlessness of ballroom dancing, the deadpan elegance of a waltz played against the extraordinary strangeness of routine space travel.

A Clockwork Orange uses Singin' in the Rain during an act of violence in a way that transforms the song permanently. No one who has seen the film can hear that song neutrally. Kubrick understood that cinema can contaminate cultural objects and he used this capability deliberately.