This article is part of a series on creative pairs. To read the introduction, click here. To read the first part of the Beatles essay, click here.

"It's like there was me, then the Beatles phase, and now I'm me again" —Paul McCartney

It's supremely odd how history would play the collaboration between John Lennon and Paul McCartney. The result of one of the most intertwined partnerships in music history, their work would consistently be reduced to static roles. It's almost as if, faced with the bound pair, a culture obsessed with individualism found a way to cleave them in two.

Take, for example, the relentless focus on "John" songs versus "Paul" songs—or sections of songs, or single lines—as though that's the skeleton key to the Beatles' inner workings.

Actually, this tradition has an impeccable source: John and Paul themselves. The irony is that the way they came to tell their own story, after their split, may speak less to the way they separated and more to the way that they remained connected.

First, consider the usual take. "Now your songs were co-credited, you know, in the Beatles era," Terry Gross said to Paul in a 2001 interview. "My understanding is, correct me if I'm wrong, that many of the songs were written by one of you or the other, although the other would do some editing on the song, but that few of the songs were actually true collaborations."

"Is that right?" she asked. "Is that accurate?"

In response, Paul gave what has become a kind of official history: In the early days, he said, he and John were constantly in each other's presence, and "everything was co-written; we hardly ever wrote things separate."

Then, after a few years, as we got a bit of success with the Beatles and didn't actually live together or weren't just always on the road together sharing hotel rooms, then we had the luxury of writing things separately. So John would write something like "Nowhere Man," sort of separately in his house outside London, and I would write something like "Yesterday" quite separately on my own, and as you say we would come together and check 'em out against each other. Sometimes we would edit a line of each other's. More often, we'd just sort of say, "Yeah, that's great."

This bit—clear, ordered, and apparently airtight—is typical of McCartney. Lennon delivered basically the same message in a 1970 interview with Jann Wenner and, typical for him, he both far overstated the case and then doubled around to underscore its true ambiguity.

"When did your songwriting partnership with Paul end?" Wenner asked.

"That ended," Lennon jumped in quickly, and then he paused for several seconds. "I don't know, around 1962, or something." He laughed, and it sounds like a nervous laugh, or maybe he was announcing a joke: 1962 is when Paul and John first began laying their compositions down on studio tape for George Martin at EMI.  "I don't know," Lennon went on. "I mean, if you give me the albums I can tell you exactly who wrote what, you know, and which line. I mean, we sometimes wrote together and sometimes didn't but all our best work—apart from the early days, like 'I Want To Hold Your Hand' we wrote together and things like that—we wrote apart always, you know."

Then he returned to the question and contradicted himself. "We always wrote separately," he said, "but we wrote together because … because we enjoyed it a lot sometimes, and also because they'd say, 'Well, you're going to make an album?' We'd get together and knock off a few songs, you know, just like a job."  

John's statement sounds like nonsense: "We always wrote separately but we wrote together." It's impossible to straighten into a literal meaning. But it actually captures the reality of their collaboration quite well.

Sometimes, it's true, songs tumbled out of their creators in whole. It's telling that McCartney seized the two clearest examples—"Yesterday" and "Nowhere Man"—when he described the collaboration to Terry Gross. On waking one morning, Paul sat down and practically transcribed the music for "Yesterday" on piano, using nonsense lyrics at first—"Scrambled egg … ." "Nowhere Man" has a parallel story. After five hours trying to write a song, and failing, John gave up in frustration. "Then," he told Playboy in 1980, " 'Nowhere Man' came, words and music, the whole damn thing as I lay down."

Neither experience was typical. For one thing, even when John and Paul were apart, they were constantly in touch, according to Cynthia Lennon's account of John's process. (She had a firsthand view through mid-1968). John had a studio in their attic and he went there at all odd times. "Then," Cynthia wrote, "there would be phone calls back and forth to Paul, as they played and sang to each other over the phone."

John and Paul also met frequently to work. In 1967, the journalist Hunter Davies sat in on several of those sessions. One priceless account shows the slow, ambling course of discovery on the way toward "A Little Help From My Friends."

They started around 2 p.m. in Paul's workroom, a narrow, rectangular space full of instruments and amps and modern art. The previous afternoon, they'd gotten the tune for the song. Now they were trying to polish the melody and write lyrics. John took up his guitar and Paul banged at the piano. "Each seemed to be in a trance," Davies wrote, "until the other came up with something good, then he would pluck it out of a mass of noises and try it himself."

"Are you afraid when you turn out the light?" John offered.

Paul repeated the line, agreeing it was good. John said they could begin each of the verses with a question. He offered another one. "Do you believe in love at first sight?" "No," he interrupted himself. "It hasn't got the right number of syllables." He tried singing the line breaking it in two between "believe" and "in love."

"How about 'Do you believe in a love at first sight?' " Paul offered. John sang that, and instantly added another line. "Yes I'm certain that it happens all the time." They repeated these three lines over and over again. It was now five o'clock. Some others came by, and as they bantered about, Paul started doodling on the piano before breaking out into "Can't Buy Me Love." John joined in, shouting and laughing. Then they both shouted out "Tequila."

"Remember in Germany?" John said. "We used to shout out everything." They did the song again, with John throwing in words in every pause—"Knickers" and "Duke of Edinburgh" and "Hitler."

"Then, as suddenly as it had started," Davies wrote, "they both went back to the work at hand."

John sang a slight modification of the line they'd agreed on. "What do you see when you turn out the light?" Then he answered the question: "I can't tell you, but I know it's mine." Paul said that would do and wrote the four lines on a piece of exercise paper propped up on the piano. Then they broke for cake.

Had Jann Wenner picked up Sgt. Pepper's Lonely Hearts Club Band, pointed to the second track, and took Lennon up on his offer to say "exactly who wrote what, you know, and which line," could Lennon have said honestly he had written that day's material? Sure. The only explicit edit of Paul's was the indefinite article "a."

Yet, looking for concrete divisions in their labor, though not irrelevant, can certainly seem myopic. It feels, from Davies' account, as though the two men were bound by a thousand invisible strings.

Davies looked on at the partners before Yoko, before The White Album— "the tension album" Paul said. But tension had always been key to their work. The strings connecting them hardly dissolved, even in the times when the collaboration was adversarial, the kind of exchange that Andre Agassi described when he said that, if he hadn't faced Pete Sampras, he'd have a better record, "but I'd be less." Picking up on that incisive line, Michael Kimmelman wrote in his review of Agassi's book Open that "rivalry … [is] the heart of sports, and, for athletes, no matter how bitter or fierce, something strangely akin to love: two vulnerable protagonists for a time lifted up not despite their differences but because of them."

But even in the hardest times, it's hardly true that John and Paul stopped working together. In what was, ostensibly, the nadir of their partnership in January 1969, their concert on the Apple rooftop shows the two men in profound sympathy. At one point, John forgot a verse to "Don't Let Me Down." He and Paul proceeded in perfect sync as John sang nonsense lyrics, then returned to the top of the verse as if nothing had happened. You can see on the film how John shoots Paul a look of pure boyish glee. Several months later, when John wrote "The Ballad of John and Yoko," he rushed to Paul's doorstep. With George and Ringo out of town, he insisted they go straight to the studio. They cut the song in one long day, John taking the guitars and lead vocal, Paul on bass, drums, piano, maracas—and coming in with breathtaking harmonies.

We typically look back on a broken partnership and assume it suffered from distance and alienation. But as Arthur and Elaine Aron have shown, relationships can suffer just as much from too much closeness and the consequent loss of control or identity. People describing these kinds of relationships use words like suffocating, smothering, overwhelming. They've lost too much of their individual distinction into a shared whole.

There's good reason to believe this happened with John and Paul. To understand why, we need to consider the reality of the early 1970s. Today, with Wikipedia and mountains of Beatles books, we have fantastic detail on the minutiae of their individual contributions. But when they worked together, and when they split, they were, as writers, just as they appeared in their credits: Lennon/McCartney. When John took tea at the Plaza Hotel in the 1970s, the pianist would serenade him with "Yesterday." On a TV show, the band played "Michelle" during a break. "At least I wrote the middle eight on that one," John said.

It was as though the partners had deposited every asset of reputation and identity into a joint bank account. After their split, they stood in line, day after day, to take the maximum withdrawal. Of course, there were literal bank accounts—immense financial and practical complications of their divorce. But what's interesting here is their self-conception—their desperate need to individuate. One of their most common words after the split was me. From Paul's self-questionnaire in April 1970:

Q: Did you enjoy working as a solo?

PAUL: Very much. I only had me to ask for a decision, and I generally agreed with me.

The next year, John told Jann Wenner that his first solo album was the "best thing I've ever done." "Now I wrote all about me and that's why I like it," he said. "It's me! And nobody else. That's why I like it." Paul got to the identity question even more directly in an interview with Life magazine. "It's like there was me, then the Beatles phase, and now I'm me again."

As they gave their history, John and Paul became relentless in dissecting their own work. This formed the bedrock of the history of their collaboration. Asked about the songs, they often used the possessive: "That's John's," Paul would say, or "That's mine." John would do the same. It's telling that two men with notoriously poor memories—neither knew how many times they'd been to Hamburg, for example—left in doubt the authorship of only a single melody in a single song ("In My Life").

Of course, they did make many distinct and identifiable contributions. But with the ferocity of their claims for singular ownership, did they protest too much?

Even their bitterness after the split speaks to connection. After Paul's press release, and his public shot at his ex-partner's exhibitions ("too many people preaching practices"), Lennon wrote a song called "How Do You Sleep" with the lines "Those freaks was right when they said you was dead" and "The only thing you done was Yesterday" and "The sound you make is Muzak to my ears."

This is nasty stuff. But the opposite of intimacy isn't conflict. It's indifference. The relationship between Paul and John had always been a tug of war—and that hardly stopped when they ceased to collaborate directly. Asked what he thought Paul would make of his first solo album, Lennon said, "I think it'll probably scare him into doing something decent, and then he'll scare me into doing something decent, like that."

Predictably, Paul took a mostly sunny air in interviews after the breakup—and he returned to an admiring view of John that would grow over the years. He even thanked his ex-partner for ushering in a new and vital phase of life. "I sort of picked up on his lead," Paul said in 1971. "John had said, 'Look, I don't want to be that anymore. I'm going to be this.' And I thought, 'That's great.' I liked the fact he'd done it, and so I'll do it with my thing. He's given the okay."

With John, the basic ambiguity came through—his loving Paul, and needing to stay separate. On The Mike Douglas Show in 1972, a young man in the audience asked John if "How Do You Sleep" was "vicious." John at first denied it, saying he had just had dinner with Paul who was laughing and smiling. "If I can't have a fight with my best friend," he said, "I don't know who I can have a fight with."

Douglas was just moderating, but it seems he couldn't resist this striking declaration. He turned to Lennon. "Is he your best friend, Paul?"

"I guess in the male sex he," John stammered, "— he was. I don't know about now, because I don't see much of him, you know."

Two years later, John would mix up his tenses when describing Paul in an even more revealing way. It was Thanksgiving night in 1974, when he joined Elton John at a sold-out show at Madison Square Garden.

Lennon wore a black silk shirt, a black jacket, and a necklace that dangled a flower over his chest. He had on his usual "granny" glasses with dark lenses. His thin, brown hair fell down past his shoulders. After storming through "Whatever Gets You Through the Night" and "Lucy in the Sky With Diamonds," Lennon came to the microphone to round out the set.

"I'd like to thank Elton and the boys for having me on tonight," he said. "We tried to think of a number to finish off with so I can get out of here and be sick, and we thought we'd do a number of an old, estranged fiance of mine, called Paul. This is one I never sang. It's an old Beatle number and we just about know it."

The song was "I Saw Her Standing There."

Though he lived another six years, John Lennon never took the stage for a major show again. His strange words have a peculiar and lasting echo. By then, Paul and John had been the most famous exes in the world for four years. But somehow, they were still "fiances"—prospective spouses. As much as had passed, the energy between them was always in front of them—always, somehow, in the future.

Coming next week: "Meet the Idiots," an artist-illustrator pair put their partnership under the microscope. If you haven't already, read the introduction the creative pairs series: " Two Is the Magic Number."

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