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Billy Corgan has some harsh words for John Mayer, following the singer/songwriter's quips to Playboy magazine about Jessica Simpson being "sexual napalm."

"As far as it pertains to her. I think for any person who has celebrity to sort of drop rocks at somebody else's feet like that -- there's things you should really just keep your mouth shut on. There's things that should just be left alone," Corgan, who is rumored to be dating Simpson, tells Rolling Stone magazine.

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The Smashing Pumpkins frontman believes Mayer is trying to self destruct, telling the publication, "Rather than take a year off or change his musical direction … some part of it is irritating his soul to the point where he's trying to blow it up. Certainly a talented guy, but empathetically, standing on the sidelines, it's hard to watch someone literally burn their career to the ground -- speaking as somebody who's done it."

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Simpson recently opened up about ex-boyfriend Mayer's interview on the "Late Show with David Letterman," saying, "Yeah, I mean, normally you would think that somebody you care about would keep those intimate details to himself…," she went on to say. "I mean, it was definitely a compliment, in a way, but I don't really want people to know that about me. That's, you know, I'm like the good girl and then that happens."

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