The Beatles legend is largely happy with the way things have panned out and worries that if something in his past was altered, he might not be where he is today.
However, the death of his first wife Linda, who passed away in 1998 after a battle with cancer, is one thing he wishes he could change.
"If I had a time machine, I couldn't be bothered to change anything to tell you the truth. Obviously, there've been loads of thinks I would love to change, like my wife Linda dying. I would love to be able to change that. But life is what it is. So get on with it and enjoy what you've got," he told Q magazine.
The 70-year-old star is proud of the legacy he has left in modern music. He and his Beatles bandmates John Lennon, George Harrison and Ringo Starr are still huge influences for many modern groups, which Paul finds both flattering and amusing.
Much has been made of the difficult relationship the rest of the band had with John's wife Yoko Ono, who many blamed for causing the Beatles' split in 1970. Paul admits things were tricky, although he has now made peace with Yoko.
"Because we'd been such a tight-knit group, the fact that John was getting pretty serious about Yoko at that time, I can see now that he was enjoying his newfound freedom and getting excited by it," he explained.
"But when she turned up at the studio and sat in the middle of us, doing nothing... I still admit now that we were all cheesed off. But looking back on it - [me and Yoko] have talked about this - I think she realises it must have been a shock for us. But lots of things that went down were good for us, really. At the time though, we certainly did not think that."