The Beatles created music together for over a decade, writing iconic songs such as Yesterday, Something, Hey Jude and I Wanna Hold Your Hand. The band didn’t always see eye-to-eye, however. Paul McCartney recently spoke out about his experience growing up, writing and recording music with John Lennon on the Disney Plus show McCartney 3, 2, 1.

Speaking candidly about Lennon, who was assassinated on December 8, 1980, McCartney said: “Thinking back on it, it’s crazy.

“[John] wore glasses and I didn’t, so if we got into an argument I would call him ‘four-eyes.’ Four-eyes!”

John didn’t take the insult sitting down, however.

McCartney went on: “He would go: ‘Pigeon chest!’ My chest was not as developed as his, or whatever.”

“So you know, we did all that. But these things obviously bring you together.”

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McCartney delved into the backstory of both himself and Lennon growing up by comparing their upbringings and their families.

He said: “I always thought everyone had loving families. Of course, later I found that’s not true. And some people are very unfortunate.”

While McCartney grew up with two loving parents, Lennon was not as lucky as a child.

The singer, who would go on to write Imagine, lost his mother, Julia Lennon, in a car accident on July 15, 1958.

McCartney added: “It’s how he got through that childhood. But I was much more open and just more… ‘Everything’s great!’ Optimistic.”

The singer then recalled writing a song from a different perspective from Lennon, saying: “I would write: ‘It’s getting better all the time.’ And he would go: ‘It couldn’t get much worse.’ Which was like, the perfect foil for that song.

“So I loved the way he would always add a little cynicism.”

Throughout the exciting TV show about The Beatles history, McCartney spoke candidly about his relationship with Lennon and the other members of the band – George Harrison and Ringo Starr.

During the final episode, Rubin told McCartney what Lennon really thought of him.

He revealed Lennon described the musician as “one of the most innovative bass players that ever played bass”.

McCartney replied: “That’s beautiful. I hadn’t heard that before. He never said that to me. But it’s nice to hear that he said it to someone.”

McCartney 3, 2, 1 is available on Disney Plus now.