With three successful records under his belt, John Mayer could pretty much do anything he wanted for his fourth album, 'Battle Studies.' So not only did the singer-songwriter move away from complex guitar lines in favor of a simpler sound, he decided -- on a whim -- to have Taylor Swift provide guest vocals on a song.

Mayer tells PopEater that the decision was as simple as "just my imagining hearing her voice in harmony with mine on this song that was sort of stemming up in my brain. It was a little bit like writing a screenplay with an actor in mind. I went to this place in my mind like Taylor and I were in the '70s playing on 'The Johnny Cash Show.'"

In an age when the slightest misstep or misunderstanding can cause controversy -- see Harry Connick Jr.'s recent blackface troubles -- John Mayer isn't playing it safe. In fact, his new single, 'Who Says,' boldly begins with the line "Who says I can't get stoned?"

"It's not a dirty word. It's not a curse word," Mayer tells PopEater of the first single from his upcoming album, 'Battle Studies.' "It's a presentation of an idea that makes people think a little harder about what they're listening to, which I don't think is the worst thing in the world."

When it came time to film video for 'Who Says,' John Mayer's first single off his forthcoming album 'Battle Studies,' the singer/guitarist decided to give fans a realistic glimpse into his life out of the spotlight. "It's sort of a country-ish song and I had the idea juxtapose it over something really metropolitan," Mayer tells PopEater of the NYC-filmed clip. "I want people to watch the video and feel like they hung out with me for a night, which is to say tired and exhausted," he adds, laughing.

The video, directed by Anthony Mandler, features scenes inspired by Mayer's exploits with his friends. Watch 'Who Says' after the jump!