I seriously like noam chomsky

I concur with all of the comments so far, especially Richard Carrier as an author and historian. I am surprised though that no one has mentioned AronRa, he is knowledgeable in Evolution and Biology, but not as much as Richard Dawkins. This is harder than I thought it would be, but overall knowledgeable I'd like to throw AronRa's name on the pile.

I don't think you can really measure this. Most prominent atheists specialize in various fields of which they will be very knowledgeable. As far as a person with "total amount of knowledge" it is most likely someone we have never heard of, learning is time consuming and being well know is not conducive to free time. Not a good answer I know, but really the best I have to give.

As for countering religious claims the late/great Christopher Hitchens always impressed me.

I've been very impressed with the author Steven Pinker. I have been reading his book, Enlightenment now, and would encourage everyone to get the book and read it. It has helped me to think about life and people much differently than I did before.

Wow didn't expect this much of a turn out. As far as morality I would go with Sam Harris. I've listened to him for years and agree with him very often. Michael Shermer is a good one as well, his video from Cambridge is one of my favorites. Dennett has my vote on the philosophical side. Dillahunty knows the bible back and forth because he was studying to be a preacher before joining our side lol. I can't get enough of the atheist experience. Dillahunty can be ruthless at times and its great. Dawkins and Laurence Krauss are the two I started with first with their debates on religion (pure gold). Bill Maher is one of my favorites as well. I know I said in the post most knowledgeable today but I wish Hitchens was still with us to spread his wisdom. Thanks for the comments

Yourself. You make your decisions based on your experience. No one else can do that for you.

Nobody mentioning Sam Harris?

Knowledgeable about what? Philosophy: Daniel Dennett. Morality: Sam Harris. How to communicate well: Peter Boghossian, Anthony MagnaBosco, Ried Nicewonder. The bible: Matt Dillahunty and pretty much everyone on atheist experience and talk heathen. Evolution: Richard Dawkins, Aron-Ra. Engineering: Venaloid, thunderfoot. Cosmology: Lawrence Krauss, Niel Degrasse Tyson. Politics: Contrapoints. Comedy: George Carlin, Russel Brand, Ricky Gervias, Bill Maher Education: Hank Green. Supernatural claims: James Randi, Penn and Teller, Captain Disillusion

He may nhto be the mos knowledgeable, but Bill Maher is the most fun to listen to.

I would have to say Dan Barker and Annie Laure Gaylor co-presidents of FFRF. Dan has written numerous books and songs ant the 2 of them travel widely and probably are the most active in this area.

Bill Maher.......

Matt Dillanunty.is quiite intelligent and expresses his ideas well.

Jerry Coyne, Dawkins, Dennett, Matt Dillahunty just to name four

Can’t name anyone as you don’t say what “knowledge “ you refer to. I don’t really follow any of the prominent and vocal atheists. If they are able to turn large numbers of believers away from their superstitions and make them see reason that is good, but I have never believed in god so don’t feel the need to have my views confirmed by them.

knowledgeable about what? you don't have to be a scientist to know there are no gods. there are all kinds of knowledge. a good sense of logic -- a good sense of sense you might say -- is a kind of knowledge. i think ron reagan and ricky gervais are great! they know how to communicate to people. that's important knowledge.

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