Here’s a thought: at some point we’ll run out of songs.
Sure, there are a bunch of reasons why this won’t happen, but it’s still one of those random thoughts that entertains my brain. It falls into the realm of trivia, but I think it’d be interesting to make an educated guess at the number of possible songs.
Here are the numbers I’d need:
- Most pop songs are written at a fairly basic vocabulary level. What’s the average reading level, and how many words are in that vocabulary?
- What’s the average number of words in a pop song (not counting repeated phrases like the chorus and refrain)?
Those two numbers combine to give a seemingly infinite number of songs… but the vast majority of them would be gibberish and hard to pass off as real language. So we need some rules.
A portion of the song should make sense
- Parts of the song need to be understood by a human, especially the chorus. (Billy Joel’s “We Didn’t Start the Fire” is a song where only the chorus makes sense.) Grammatical correctness isn’t the gold standard, since it’s possible to build grammatically correct combinations of words that mean nothing.
- Really, just the chorus is what matters.
- Phrase length can’t be infinite, because we’d lose track of the meaning somewhere along the way. So there must be an upper bound on the number of words.
- Rhyme isn’t required in lyrics, but it’s considered desirable in songs.
Combine the number of words commonly used with the average number of words in a song and it’s possible to calculate all the combinations and permutations. Then the song has to make sense, which knocks the number of possible songs down quite a bit.
… probably need a few more constraints to run this down.
