Scientist and musician Daniel Levitin wrote about the ubiquity of Beatles songs a while back:

One hundred years from now Beatles songs may be so well known that every child will learn them as nursery rhymes, and most people will have forgotten who wrote them. They will have become sufficiently entrenched in popular culture that it will seem as if they’ve always existed, like Oh Susannah, This Land Is Your Land, and Frère Jacques.

Why can we listen to certain songs across a lifetime and still find pleasure in them? Great songs activate deep-rooted neural networks in our brains that encode the rules and syntax of our culture’s music. Through a lifetime of listening, we have learned what is essentially a complex calculation of statistical probabilities of what chord is likely to follow what, and how melodies are formed. Skilful composers play with these expectations, meeting and violating them in interesting ways. In my laboratory we’ve found that listening to a familiar song that you like activates the same parts of the brain as sex or opiates do. But there is no one song that does this for everyone; musical taste is both variable and subjective…

On the bus to my office, the radio played And I Love Her and a Portuguese immigrant my grandmother’s age sang along. How many people can hum even two bars of Beethoven’s Fourth, or Mozart’s 30th? I recently played one minute of these to an audience of 700 people – professional musicians included – but not one recognised these pieces. Then I played a half-second of two Beatles songs – a fraction of the first “aah” of Eleanor Rigby and the guitar chord that opens A Hard Day’s Night – and virtually everyone shouted out the song names, more than could recognise the Mona Lisa.

To a neuroscientist, the Beatles’ longevity can be explained by the fact that their music creates subtle and rewarding schematic violations of popular musical forms, causing a symphony of neural firings from the cerebellum to the prefrontal cortex. To a musician, each listening showcases subtle nuances not heard before, details of arrangement and intricacy that slowly reveal themselves across hundreds or thousands of listenings. I have to admit, they’re getting better all the time.

While the neuroscience piece is interesting in its own right, a sociologist might be more interested in thinking about what songs make it to this level of common knowledge or become part of cultural narratives across societies. How many times does a song have to be played? Does it matter in what venues the song is performed? I could imagine a mega radio hit vs. a lesser known song that gets licensed dozens of times in the coming decades in commercials. Does the relative importance of the musical artist matter? Some of this has to do with diffusion and the various gatekeepers at play. The Beatles likely have all these factors (except the commercials) in their favor as they were a cultural phenomenon, produced numerous #1 singles around the world, changed the music industry (from recording to stopping touring), and were generally liked by critics.

Just thinking back, I feel like I only tend to hear this argument about what songs will last into the future when people are worried about their idea of bad music (maybe boy bands of the late 1990s, Brittany Spears, Lady Gaga, etc.) becoming the equivalent nursery rhymes.