This is from an old interview, and a well-known story about Paul McCartney's not know if "Yesterday" was original or not:
Clash: Moving onto ‘Yesterday’, that song was apparently a year in the making - what took so long getting that right?
Paul McCartney: Was it? I don’t remember it taking a year. It must have been from when I actually had the melody to when I’d finished it all. I dreamed the melody one day in London when I was staying at Jane Asher’s house, who was my girlfriend at the time, and I was staying there and I woke up one morning with the song in my head. So, I went round for weeks - first of all to John, and then to George, Ringo, George Martin, various people - and said, ‘What’s this tune, man? I can’t get it out of my head, what is it?’ And no one could figure it out, so for a couple of weeks I thought, ‘Well, I must have written it then’, cos all those people had pretty good knowledge of what songs were either around or had been. So, I had the tune, and then I blocked it out with, [sings verse melody] “Scrambled eggs / Oh my baby, how I love your legs”, which was the first lyric, and I just used to goof with that for a while. And then, I was reminded recently by Bruce Welch, of Cliff Richard’s band The Shadows, that he had a flat in the south of Portugal, and he was a mate and he said to me, ‘If you ever want to use the flat, be my guest.’ I don’t know if he ever expected me to show up, but I did! I landed in Lisbon with Jane Asher, and we had to drive from there down to the Algarve. It was a long, dusty, hot drive with nothing to do, so sitting in the back of this car I just started thinking of words, and over those three hours or so, I figured out what I wanted to do. I’d forgotten that bit, but Bruce reminded me recently; he said, ‘Yeah, don’t you remember? You came to the flat and I was just moving out, you were going to move in, and you said, ‘Have you got a guitar?’’ And he said, ‘Yeah, but it’s right-handed - you’re left-handed.’ I said, ‘It doesn’t matter.’ I could just about fudge the chords. He said to me, ‘You sang ‘Yesterday’ - you had all the words to it.’ So yeah, he reminded me of that. And then I’m not sure how long it took to get it to the sessions - maybe we weren’t recording at that point; it sounds like we weren’t if I was on holiday... We’d be having a break or something. So probably when we got back in the studio in Abbey Road I then [started it], so I’m not sure if that whole process was a year but that was the story.
