During a recent chat with Harper’s Bazaar magazine, Keith Richards spoke frankly about his and Mick Jagger‘s songwriting process for some of their greatest tunes. Richards explained the nuts and bolts of songwriting, revealing, “There are only two kinds of songs, honey. The beautifully smooth ones that are plainly obvious when they come to you, and the ones that give you a hard time.”

Richards offered up the back story to the 1978 Some Girls classic, “Beast Of Burden”: “Those who say it’s about one woman in particular, they’ve got it all wrong. We were trying to write for a slightly broader audience than just Anita Pallenberg or Marianne Faithfull. Although that’s not to say they didn’t have some influence in there somewhere. I mean, what’s close by is close by! I’ve always felt it’s one of my best soul songs. It was another strict collaboration between Mick and me. I think I had the first verse — ‘I’ll never be your beast of burden’ — along with the hook, and we were still working very much in our traditional way: Here’s the idea, here’s the song, now run away and fill it in! Some of the theories surrounding it are very intriguing, but they’re about as divorced from reality as can be. I find it quite amusing that there are people in the world who spend a lot of their time trying to decode something that is, at the end of the day, completely undecodable. I mean, even I’ve forgotten the code!”