Generations and genres collided when Taylor Swift invited '70s soft pop icon Carly Simon to perform with her at Gillette Stadium in Foxboro, Mass. on Saturday night (July 27). The ladies teamed up for an amazing duet of Simon's smash 'You're So Vain.'

Swift and Simon were adorable together, jumping up and down and putting their arms around each other while performing the famous song about an ex-lover thinking he is so important, even having the audacity to assume that the song is about him. As if!

That scenario could apply to any or many of Swift's exes, so the resonance of the lyrics was clear. Regardless, Swift is clearly in love with Simon's song, as evidenced by the ebullience with which she performed.

Swift tweeted about the experience post-performance, writing, "Got to sing 'You're So Vain' with Carly Simon at Gillette Stadium tonight!!!!! Unreal. I could not possibly look up to her more."

While Swift's crowd skews young and many may not be super familiar with Simon's song -- which was released in 1972, 17 years before Swift herself was even born -- there were lots of fans singing along, as the iconic song does transcend its initial release decade.

Interestingly enough, Swift has also performed with singer James Taylor, who was married to Simon and who some believe inspired the song, even though Simon has nixed that notion.

Whatever the case, Swift takes influence from both artists, and it's all cyclical for her. She exhibited an easy and natural chemistry with Simon and it was a lovely performance.