There is as much to say about the notion of silence as there is about the number zero. The act of negation – or its seeking out – shoulders moral and practical baggage. Patrick Shen has set out to honour these arguments in a documentary that does what its title suggests. The crowd-funded film wonders what silence is and asks whether we can find it in the modern world.

There is scope here for an interesting experimental film, but Shen has taken a more conventional route. You would expect any self-respecting documentary on the subject to feature discussion of John Cage's 4'33'' – the composer's famous noiseless piece – and the director does not disappoint. You would expect a monkish presence and that is here too. Shen also encounters a young eccentric walking across the United States under a self-imposed vow of silence.

Unfortunately the film loses its nerve about halfway through and, unable to fill up the space with convincing nothingness, sets to a conversation about noise. I am interested to hear that many waiters in New York now work in environments that should legally require ear protection. I will file away the information that Mumbai is the world’s noisiest city. But none of this really belongs.

The film also defies its own arguments by filling up much empty space with plinky-plonky piano music. Such New-Age noodling is no closer to silence than the stylings of Metallica, you know.

A pleasant diversion all the same.