Kanye West is a self-proclaimed monster, and Sir Paul McCartney seems to agree. Speaking with BBC Radio, the Beatles great shared what it was like to work with Kanye. From 2014 to 2015, the two worked on three non-album singles, "All Day," "Only One," and the Rihanna-led track "Four Five Seconds." As McCartney tells it though, the collaborative sessions were held without any particular song or project in mind, and Kanye was able to turn them into something completely new.

"People say he’s eccentric which you’d have to agree with. He’s a monster. He’s a crazy guy that comes up with great stuff. So, he inspires me," McCartney said. "We sat around and I didn’t know how we were going to do it... And the thing was, if it doesn’t work, we just won’t tell anyone. That was the agreement."

McCartney then played a few chords, as he did for Kanye, noting that the rapper didn't seem too impressed by the melodies offered. "You just work with him and then you leave it for a little while and let it marinate and hope he gets back to you," he said, remarking that a simple whistled melody was suddenly turned into the ripping opening notes of "All Day."

McCartney says he was pleased with the final outcome of "All Day." Watch as he details his experience working with Kanye in the video up above and recreates some of the fateful sessions he and Kanye shared.

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