The Simpsons: 10 Moments More Important Than You Realised

Sir Paul McCartney is one of the most influential musicians of all time. As a member of The Beatles, he helped shape modern music, and influenced generations of fellow singers (and players) to come.

He, along with his first wife Linda, also revolutionised vegetarianism with their range of meat-free products. Oh, and he also single-handedly changed The Simpsons forever.

Paul and Linda made a guest appearance in the episode Lisa the Vegetarian, where they help convince the Simpson child to stick to her anti meat-eating stance. After this episode, Lisa never willingly eats meat again, and that's all down to the former Wings frontman.

As one of his conditions for coming on the show, McCartney requested that Lisa must not revert back to being a meat-eater for the rest of the series. The writers obliged, and Lisa's character was changed forever.

The idea of Lisa Simpson eating meat seems laughable these days, as her vegetarianism is so deeply ingrained in her character. However, it took the writers seven years to get there, and even then, they required a push from one of the most famous men on the planet.

Thanks goodness they didn't just Let It Be...