There aren't that many accounts of John Lennon and Paul McCartney not agreeing on who wrote which parts of their songs. In fact, to a certain degree, it didn't matter — that's why the "Lennon-McCartney" songwriting name was established, since oftentimes it was hard to tell where one man's contribution ended and the other's began.

But for however synchronized Lennon and McCartney were, the reality is that two separate brains were at work when it came to their songwriting, and it did ultimately matter to each of them how those contributions were remembered.

"In My Life" from the Beatles' 1965 album Rubber Soul is a clear example of this.

John Lennon's Memory of How 'In My Life' Was Written

One thing Lennon and McCartney did not disagree on was that "In My Life" originated with Lennon.

"'In My Life' started out as a bus journey from my house on 250 [sic] Menlove Avenue to town, mentioning every place I could remember," Lennon recalled to David Sheff in 1980. "And it was ridiculous. This is before even 'Penny Lane' was written and I had Penny Lane, Strawberry Fields, Tram Sheds – Tram Sheds are the depot just outside of Penny Lane – and it was the most boring sort of 'What I Did On My Holidays Bus Trip' song and it wasn't working at all. I cannot do this! I cannot do this! But then I laid back and these lyrics started coming to me about the places I remember."

It was then that McCartney came into the picture, as far as Lennon remembered it in a 1970 interview with Rolling Stone: "I think on 'Norwegian Wood' and 'In My Life' Paul helped with the middle eight, to give credit where it's due."

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A decade later, Lennon doubled down on this memory when speaking with Sheff:

"Paul helped with the middle eight musically," he confirmed again. "But all lyrics written, signed, sealed and delivered. And it was, I think, my first real major piece of work. Up till then it had all been sort of glib and throwaway. And that was the first time I consciously put my literary part of myself into the lyric. Inspired by Kenneth Allsop, the British journalist, and Bob Dylan."

Paul McCartney's Memory of How 'In My Life' Was Written

McCartney's memory of the song's writing was a bit different.

"As I recall, he didn't have a tune to it, and my recollection, I think, is at variance with John's," he said for Many Years From Now. "I said, 'Well, you haven't got a tune, let me just go and work on it.' And I went down to the half-landing, where John had a Mellotron, and I sat there and put together a tune based in my mind on Smokey Robinson and the Miracles…

"I recall writing the whole melody. And it actually does sound very like me, if you analyse it. I was obviously working to lyrics. The melody's structure is very me. So my recollection is saying to John, 'Just go and have a cup of tea or something. Let me be with this for 10 minutes on my own and I'll do it.'"

Listen to the Beatles' 'In My Life'

McCartney recalled Lennon approving his melody and things progressing from there – more verses, etc.

In the studio, producer George Martin added his own flair by playing a little piano trick.

"There's a bit where John couldn't decide what to do in the middle," Martin recalled in Anthology, "and, while they were having their tea break, I put down a baroque piano solo which John didn't hear until he came back. What I wanted was too intricate for me to do live, so I did it with a half-speed piano, then sped it up, and he liked it."

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In short: McCartney's memory saw him with more influence over the song's music, while Lennon's insists it was only the middle eight section that came into play, the rest was all his. There is, of course, no way to know which is right for certain, and it's possible that both men's recollection was not fully correct.

But remarkably, "In My Life" was one of just two instances in which Lennon and McCartney's memory appeared to significantly differ, at least according to McCartney's later memory and other research into Lennon's post-Beatles interviews. Not bad for a partnership that collaborated on a couple hundred songs.

Or as McCartney said: "I find it very gratifying that out of everything we wrote, we only appear to disagree over two songs."

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The band's sixth studio album was unlike anything else on the market when it was released on Dec. 3, 1965. 

Gallery Credit: Allison Rapp