John Lennon talks out on writing Beatles songs with Paul songs which are heavily identified with Paul, like "Eleanor Rigby" on which I wrote a good half of the lyrics or more.
This is an excerpt from a Rolling Stone interview. to read the full article click here
Who wrote "Nowhere Man"?
Me, me.
Did you write that about anybody in particular?
Probably about myself. I remember I was just going through this paranoia trying to write something and nothing would come out so I just lay down and tried to not write and then this came out, the whole thing came out in one gulp.
What songs really stick in your mind as being Lennon-McCartney songs?
"I Want to Hold Your Hand," "From Me To You," "She Loves You" – I'd have to have the list, there's so many, trillions of 'em. Those are the ones. In a rock band you have to make singles, you have to keep writing them. Plenty more. We both had our fingers in each others pies.
I remember that the simplicity on the new album was evident on the Beatles double album. It was evident in "She's So Heavy," in fact a reviewer wrote of "She's So Heavy":
"He seems to have lost his talent for lyrics, it's so simple and boring." "She's So Heavy" was about Yoko. When it gets down to it, like she said, when you're drowning you don't say "I would be incredibly pleased if someone would have the foresight to notice me drowning and come and help me," you just scream. And in "She's So Heavy," I just sang "I want you, I want you so bad, she's so heavy, I want you," like that. I started simplifying my lyrics then, on the double album.
A song from the 'Help' album, like "You've Got to Hide Your Love Away." How did you write that? What were the circumstances? Where were you?
I was in Kenwood and I would just be songwriting. The period would be for songwriting and so every day I would attempt to write a song and it's one of those that you sort of sing a bit sadly to yourself, "Here I stand, head in hand. . . ."
I started thinking about my own emotions – I don't know when exactly it started like "I'm a Loser" or "Hide Your Love Away" or those kind of things – instead of projecting myself into a situation I would just try to express what I felt about myself which I'd done in me books. I think it was Dylanhelped me realize that – not by any discussion or anything but just by hearing his work – I had a sort of professional songwriter's attitude to writing pop songs; he would turn out a certain style of song for a single and we would do a certain style of thing for this and the other thing. 
What about on Rubber Soul, "Norwegian Wood"?
I was trying to write about an affair without letting me wife know I was writing about an affair, so it was very gobbledegook. I was sort of writing from my experiences, girls' flats, things like that.
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Where did you write that?
I wrote it at Kenwood.
When did you decide to put a sitar on it?
I think it was at the studio. George had just got the sitar and I said "Could you play this piece?" We went through many different sort of versions of the song, it was never right and I was getting very angry about it, 
You also have a song on that album "In My Life." When did you write that?
I wrote that in Kenwood. I used to write upstairs where I had about ten Brunell tape recorders all linked up, I still have them, I'd mastered them over the period of a year or two – I could never make a rock and roll record but I could make some far out stuff on it. I wrote it upstairs, that was one where I wrote the lyrics first and then sang it. That was usually the case with things like "In My Life" and "Universe" and some of the ones that stand out a bit.
