The best argument for Abbey Road as the greatest album in the history of popular music lasts sixteen minutes and occupies the second half of the vinyl. It is not a song. It is not a set of songs. It is something else.

Between “You Never Give Me Your Money” and “The End,” or “Her Majesty,” there are eight fragments that on their own would not be complete songs. They are sketches, half-finished ideas, scraps of melody that any band would have discarded or filed away for later. McCartney took them, arranged them, connected them, and built from them something that works the way a cathedral works: each piece is modest, the whole is overwhelming.

The idea was his. This matters because it tends to get lost in the collective narrative of the Beatles, where everything is collaboration and group genius. The Side B medley of Abbey Road is a McCartney project. He proposed the structure, designed the transitions, talked the others into it. Lennon, who by that point wanted the opposite, separate songs, direct, no artifice, went along reluctantly. Harrison contributed “Here Comes the Sun” and “Something” to Side A, two of the best songs on the record, but the medley is not Harrison territory. And Ringo did what Ringo always did: exactly what the song needed, not a note more, including the only extended drum solo in the entire Beatles discography, right before “The End.”

What McCartney did with the medley is essentially what a film director does with montage. Eisenstein theorised it in the twenties: the juxtaposition of two images creates a meaning that exists in neither one separately. McCartney did the same thing with musical fragments. “Sun King,” a drowsy Lennon singing in made-up Italian over bossa nova chords, means nothing on its own. “Mean Mr. Mustard” and “Polythene Pam” are minor vignettes, almost jokes. “She Came in Through the Bathroom Window” is an anecdote turned into a song. None of these pieces, in isolation, would make a list of great Beatles songs. But in sequence, with the transitions McCartney designed, they produce something that is more than the sum of its parts in a way that is not metaphor but literal description.

The final sequence is where it all converges.

“Golden Slumbers” opens with McCartney at the piano singing “Once there was a way to get back homeward.” The melody has a precise origin: McCartney was at his father’s house in Liverpool, saw a score of a sixteenth-century lullaby by Thomas Dekker sitting on the piano, couldn’t read music well enough to play the original tune, so he wrote a new one to the same words. That is McCartney in his purest state: taking something that belongs to someone else and making it his own with a naturalness that erases the line between invention and discovery. The melody he came up with is devastating, one of those melodies that sound as though they always existed, as though he simply dug it up.

“Golden Slumbers” bleeds without a pause into “Carry That Weight,” where the whole band sings “Boy, you’re gonna carry that weight a long time.” In 1969, when they recorded it, it was a song about the tensions within the group, about the contracts, about Apple Corps falling apart, about the burden of being the Beatles. But great songs outgrow their context, and “Carry That Weight” became something much wider: a song about the price of anything worth having, about the fact that important decisions don’t end when you make them but stay with you for good. There is a reason McCartney still plays it live in his eighties and people weep. They don’t weep out of nostalgia. They weep because the song states a truth about adult life that needs no explaining.

And then “The End.” Ringo plays his drum solo. Lennon, McCartney, and Harrison trade guitar solos, two bars each, three rounds, like a conversation between three people who no longer talk but who still know how to play together. It is the last time the three of them played guitar together with that level of intention. And then silence. And then McCartney sings: “And in the end, the love you take is equal to the love you make.”

A couplet. Thirteen words. McCartney said it took him considerable effort because he wanted the last line the Beatles ever sang to be something worthy, something that measured up. It is one of those phrases that sounds like an ancient proverb, as though Marcus Aurelius had said it or someone had stitched it into a medieval tapestry, but it was written by a man from Liverpool who was twenty-seven years old.

After that, a minute of silence, and “Her Majesty” appears, a twenty-three-second fragment McCartney had cut from the medley and that an engineer stuck at the end of the tape by accident. It is the perfect joke after the sermon, the wink that keeps the solemnity from becoming unbearable. The Beatles always knew when to release the pressure, even when they weren’t doing it on purpose.

There is something I want to say about the medley that has nothing to do with music and everything to do with what it represents as a way of thinking. McCartney, in designing that structure, was making a wager: that the fragment is more powerful than the whole. That a thirty-second sketch placed well is worth more than a complete four-minute song. That art is not only about writing good things but about knowing what order to put them in. It is an editor’s idea, a montage artist’s idea, an architect’s idea. And it runs against everything rock valued in 1969, which was individual expression, the song as autonomous unit, authorship as solitary act.

Lennon didn’t think that way. Lennon believed in the song as direct gesture: you feel something, you record it, you don’t layer things on top. It is a valid philosophy and it produced extraordinary work. But the Abbey Road medley could not have existed under that philosophy. It exists because McCartney thought like a classical composer, like someone who understands large-scale form, the arc, the way parts serve the whole. And that difference, that tension between Lennon’s immediacy and McCartney’s architecture, is what defines the Beatles more than anything else. Without Lennon, McCartney would have built cathedrals that were perfect and slightly cold. Without McCartney, Lennon would have left behind brilliant, scattered sketches. Together they made Abbey Road, which has both.

The Side B medley is, I believe, the best thing the Beatles ever did. Not the best song, because it isn’t a song. Not the best album, because it is half an album. The best thing in a broader sense: the moment where everything they knew how to do, everything they had learned in seven years of recording together, is condensed into sixteen minutes that sound like nothing that existed before and nothing that has existed since. The testament of a band that knew it was ending and that decided, one last time, to make something equal to what it had been.

And it is, fundamentally, McCartney’s work. Which is something that should be said more often.