"We Can Work It Out" very much lived up to its title, even though the million-selling stand-alone single thrusts Beatles fans into the middle of a romantic disentanglement. Paul McCartney, John Lennon and George Harrison each made key contributions that created a sum-of-its-parts triumph.

Released on Dec. 3, 1965, "We Can Work It Out" began as a loose sketch written by McCartney in one of the bedrooms of a Heswall, Cheshire, house that he purchased for his dad the year before. He brought the idea to the Beatles, and a striking new fission began.

"I wrote it as a more up-tempo thing, country and western," McCartney says in Barry Miles' Many Years From Now. "I had the idea, the title, had a couple of verses and the basic idea for it, then I took it to John to finish it off and we wrote the middle together – which is nice: 'Life is very short. There's no time for fussing and fighting, my friend.'"

That balance between light and dark, between bright positivity and sharp realism, added the first layer of complexity to "We Can Work It Out" – but certainly not the last.

"Paul did the first half; I did the middle eight," John confirmed in an 1980 interview with Playboy. "You've got Paul writing 'We can work it out,' real optimistic, you know – and me, impatient, 'Life is very short.'"

"We Can Work It Out" is broadly understood to be part of a larger group of Rubber Soul-era songs like "I'm Looking Through You" and "You Won't See Me" that dealt with McCartney's deteriorating relationship with Jane Asher. She moved out in October 1965 – the same month these sessions were held – to begin work with the Bristol Old Vic Company.

These new tensions led McCartney to an interesting place where his lyrical contributions felt more threatening, as he insists on doing things his way – while the typically aggressive Lennon is more conciliatory, even philosophical.

"The lyrics might have been personal," McCartney allowed in Many Years From Now. "It is often a good way to talk to someone or to work your own thoughts out. It saves you going to a psychiatrist. You allow yourself to say what you might not say in person."

In retrospect, "We Can Work It Out" could also be seen as a dividing line for the Beatles' two principal songwriters. Lennon wanted "Day Tripper" as the A-side, but ultimately McCartney's "We Can Work It Out" won over more listeners. These divergent creative directions, and the internal tensions that came with them, would only become more pronounced.

"They were going through one of their first periods of disunity, so maybe it's a subtext to where the band was," the Kinks' Ray Davies mused in a 2001 talk with Rolling Stone. "This is one of my little theories: Every career has its story, and if you look at the song titles, it sums up what they were doing."

Watch the Beatles' Video for 'We Can Work It Out'

The rest of "We Can Work It Out" was developed in the studio, as sessions stretched out for about 11 hours over two days – the longest the Beatles had ever spent on a single song up to that point. Early run throughs featured an acoustic guitar "fingerpicked in double time" at the end of each phrase, according to Ian MacDonald's Revolution in the Head.

Then Harrison made a song-changing suggestion: "It was George Harrison's idea to put the middle into waltz time, like a German waltz," McCartney told Miles. "That came on the session. It was one of the cases of the arrangement being done on the session."

At one point, the vocals brilliantly anticipated the tempo change by drawing out "fuss," "-ing" then "and." The Beatles also ended with a three-measure reprise of the waltz theme, made complete with Lennon's final textural contributions on a volume pedal-controlled harmonium. This old-timey found-object sound fit perfectly in the song's new context, pointing the way to the wider experimental sound palette to come on 1966's Revolver.

The Beatles ended up spending the bulk of their studio time dubbing vocals and additional instruments. The harmonium was overlaid twice, complementing Lennon's precise rhythm work, Ringo Starr's deft changes and an incredibly fun turn on the tambourine by Harrison.

"We found an old harmonium hidden away in the studio, and said, 'Oh, this'd be a nice color on it,'" McCartney remembered in Many Years From Now. "We put the chords on with the harmonium as a wash, just a basic held chord – what you would call a pad these days."

The Beatles ultimately issued "We Can Work It Out" and "Day Tripper" on what was said to be the first double A-side single then made a trio of promotional films, but almost never played the song live – likely owing to all of this musical complexity.

"After we gave both titles to EMI, the boys decided that they preferred 'Day Tripper,' but both sides are extremely good and worth a lot of plays," George Martin said back then. "As far as EMI's official policy is concerned, there is no A-side, and both will be promoted equally."

"We Can Work It Out" soon emerged as the more popular song. The single reached No. 1 in the U.K. just three days after its release, then matched that feat in the U.S. while becoming the Beatles' fastest-selling single since "Can't Buy Me Love." "Day Tripper" stalled at No. 5 in the States, underscoring McCartney's growing leadership role in the group.

Nevertheless, McCartney was unable to work it out with Asher. She announced that their engagement was off during a BBC show appearance in July 1968. By then, however, he had already met a photographer named Linda Eastman. They got married the following March and remained a couple for 29 years – until her death after a cancer battle in 1998.

Meanwhile, Lennon would eventually return to the carousel-like vibe he created during "We Can Work It Out," expanding upon it with "Being for the Benefit of Mr. Kite" on 1967's Sgt. Pepper's Lonely Hearts Club Band.


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