And the Beatles icon has never forgotten advice given to him by George Harrison when he considers his relationship with Yoko Ono.
McCartney, 71, released his 16th solo album, New, earlier this month, and regards the input from his late bandmate Lennon as integral to the writing process.
He tells Rolling Stone: “If I’m at a point where I go, ‘I’m not sure about this,’ I’ll throw it across the room to John. He’ll say, ‘You can’t go there, man.’ I’ll say, ‘You’re quite right – how about this?’ ‘Yeah, that’s better.’
“We’ll have a conversation. I don’t want to lose that.”
McCartney’s relationship with Lennon’s widow Ono has famously been fraught in the past, although they have become closer in recent years. In 2012 she thanked him for publicly saying she hadn’t been responsible for The Beatles splitting up in 1970.
Now he says: “I thought, ‘If John loved her, there’s got to be something; he’s not stupid.
“It’s like, what are you going to do – are you going to hold a grudge you never really had? George would say to me, ‘You don’t want stuff like that hanging around in your life.’”