"I was depressed at the time," McCartney said, before paraphrasing Lesley Gore's "It's My Party": "'You would be too if it happened to you.' You were breaking from your lifelong friends. We used to liken it to the army where you'd been army buddies for a few years, and now you weren't going to see them again."
McCartney then referenced another song — the barbershop standard, "Wedding Bells Are Breaking Up That Old Gang of Mine" — and said the Beatles' split came somewhat naturally, as the four members grew up, got married and moved away from each other. But the break-up still left McCartney uncertain about his future in music.
"The thing was, how are you gonna do it if you're gonna do it?" McCartney said. "You can't play all the instruments yourself onstage. And I took to the bevvies, I took to a wee dram, and it was great at first and then after a while getting up in the morning, I was a bit far gone and suddenly I wasn't having a good time."
McCartney said it was his wife Linda who convinced him to start a new project. "For some mad reason I wanted to go back to square one and do it as we'd done it in the Beatles. People said, 'Linda can't play keyboards!' And it was true, but John [Lennon] couldn't play guitar when we started — he was playing banjo chords … Looking back on it I'm really glad we did it. I could've just gone into a supergroup and rung up Eric [Clapton] and Jimmy Page, John Bonham, but I wanted to go back. We ended up playing universities and graduated to town halls, and it was funny because I'd been in Shea Stadium quite recently. You had to hold your nerve, but then you do in life."
In the Mastertapes interview, McCartney spoke about Kanye West's 2015 hit "All Day," which recycled an unused Beatles melody originally inspired by Pablo Picasso's painting, Man With a Guitar. While McCartney said the explicit lyrics of "All Day" troubled some close to him, he called it "a great record, sonically it's brilliant," and added: "I love Kanye, and he loves me. He's a monster, he's a crazy guy who comes up with great stuff, so he inspires me."Paul McCartney played Prince favorite "Let's Go Crazy" in the late singer's hometown of Minneapolis. Watch here.