I would agree that Penn Jillette is one of the more vocal and articulate atheists. I am not sure if the OP was looking for someone who is famous because they are an atheist, which seems kind of hard to do.
I think most atheists are not that vocal about it.
I am attempting to become famous for not believing in fairies. 
So Paris Hilton, then? 
:eek: 
Carl Sagan
Doing nothing, not doing everyone. 
Thomas Jefferson was not even partially an atheist. He wasn’t an atheist by any stretch of the imagination. When you stretch the definition of atheist to include people who believe in God, then it becomes meaningless no?
Voltaire.
Bertrand Russell, author of Why I Am Not a Christian.
Thanks, guys. The debate sort of dwindled, and the other drifted off before i could get back and read these. If it were still going on, I would have had to choose Ingersoll.
At any rate, thanks for all of the help.
BTW, I still don’t know who Dawkins is. I don’t pay much attention to, well, anything tha anybody hears of anymore. I know who Bill Oreilly is, Barack Obama, and I know that Ted Kennedy died sometime recently; otherwise, it’s handsomeharry’s little universe! You get the idea!
Thanks,
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Exactly who I was going to say.
If you don’t care what others believe about Christianity, why are you debating someone on the subject? :dubious:
Anyway, one well-known example of “atheist famous for being an atheist” is P.Z. Myers .
Ricky Gervais is probably about to become a famous atheist with The Invention of Lying’s DVD release.
Asia Carrera is famous for being a hot-looking atheist.
Isaac Asimov
Jefferson was nominally a Deist, but was functionally an atheist. He did not believe in a God who had any involvement with the universe after creation, did not believe in miracles, flatly rejected the divinity of Christ, frequently disparaged Christianity and religion in general, did not engage in any kind of personal worship, etc.
The most he believed was that there was “creator” of some sort, but that isn’t really enough to make him a theist in any conventional sense.
Jefferson was, at best, a “partial atheist,” and I would suggest that for all practical purposes, he was a stone non-believer.
It depends on that person’s definition of god. Jefferson’s, as far as I know, was nature.
IIRC, Albert Einstein. He is famously quoted as saying “God does not play dice with the universe”, but it was just an expression of how the world works, not an intent to affirm any religious conviction. IIRC, when he was applying to Princeton after leaving Europe, he was advised to put “Jewish” not “atheist” on his application if he wanted to get accepted more easily. After all, he may have been a Nobel Prize winner, but Princeton has to have its standards.
Karl Marx. So yeah.
Seems like the OP is asking for a person who’s famous for being an atheist. Richard Dawkins and Christopher Hitchens wouldn’t fit because they were famous for their non-atheist work first.
I’d say that Robert Ingersoll, Madalyn Murray O’Hair, Sam Harris, and PZ Myers would fit the bill.
They do fit though, because while they may been pre-eminent before they started their ‘crusade’ for atheism, atheism is what they’re famous for. It’s what made Dawkins a household name. If you say “Richard Dawkins”, nowadays most people’s first thought will be atheism, or evolution, or The God Delusion. Same thing with Hitchens - in fact I don’t even know what Christopher Hitchens is famous for apart from atheism.
Which is the same reason that Freud doesn’t really work, because while he may have been a vocal atheist, if you say “Freud” people think of sexuality, psychology, Freduian slips, etc. If you call someone’s theory “Freudian”, no one is going to automatically relate that to atheism. But they will do if you compare a theory to Richard Dawkins.
What do you mean by “nominally a Deist”? As opposed to what, a “practicing Deist”?
But it would, I think, disqualify him from being a really good example of a famous atheist.
From what I’ve read (including here on the SDMB and elsewhere), there’s some controversy over whether Einstein did or did not believe in a God that was anything more than a metaphor for the Universe as a whole. In any case, atheism is not the first thing most people think of when they think of Einstein.
My answer to the OP’s question: Richard Dawkins is the first “famous atheist” I thought of, but really, I think Madalyn Murray O’Hair may be the best example of someone who is famous primarily for being an atheist.
Actually, most folks will wonder if it’s that guy from Hogan’s Heroes and Family Feud.