Paul McCartney compares Kanye West to Andy Warhol

Paul McCartney wasn't sure about working with Kanye West. When the unlikely duo got together in 2014 to work on a series of songs, the former Beatle quickly found himself in the most unusual studio scenario he'd ever seen, struggling to figure out how, or if, he could make it work with the unconventional hip-hop icon.

Sir Paul describes their coming together in a new Rolling Stoneinterview, where he compares his "Only One" collaborator's creative process to that of Andy Warhol. "I didn't know his system. I'd heard things like, 'He's got a room full of guys working on riffs, and he walks around going, 'i like that one,'" McCartney said of 'Ye's allegedly distinctive musical M.O.

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The only agreement Macca, 74, made with West going in was that if the pairing didn't feel right they wouldn't tell anyone it happened. "It reminded me of Andy Warhol, these artists who use students to paint their backgrounds and things. It's a well-used technique," McCartney said of the sessions that also produced "All Day" and the Rihanna collabo "FourFiveSeconds." "I thought, 'I don't know how I'm going to fit into that, but let's see. Here goes nothing.'"

Their work on "All Day" included a guitar lick McCartney originally wrote in 1969 but never used, which Paul said came about when he and late wife Linda were at the hospital after she gave birth to their first born, Mary. "She was recuperating – I'm sitting around eating chips with my guitar in the clinic, goofing around with it," he said. "And there was a picture on the wall that I'd been looking at for days – Picasso, 'The Old Guitarist.' The guy held the guitar like this [strikes the pose from the painting], and a lightbulb went off in my head: 'What chord is that?' It looked like it was two strings. 'You know what would be cool? To write a song with only two fingers.' So I wrote this thing [plays the melody]."

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When they were working on songs, McCartney said he told Kanye the story and whistled that little guitar bit for him. "His engineer was recording it, and it went into the pool of ingredients. Kanye was just collecting things," he said, recreating the moment when he heard the mix to "Only One" and finally understood where he fit into the Kanye constellation. "We weren't going to sit down and write a song so much as talk and spark ideas off each other. It was only when I got this song, the Rihanna record ["FourFiveSeconds"] and 'Only One,' the three tracks we did, that I went, 'I get it. He's taken my little whistle-y thing.' It returned to me as an urban hip-hop riff. I love that record."

Is 'Ye a genius in McCartney's eyes? Having worked with a few (and arguably being one himself), Paul said he doesn't throw that word around carelessly. "I think he's a great artist," he said.

Read the whole Rolling Stone interview here.

See more from Paul in the gallery below!

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