Atheists: Does not believe in god or gods. Possibly even no belief in the supernatural.
Agnostic: Does not follow any particular religion, does believe in god or gods.
Agnostic: Does not follow any particular religion, does believe in god or gods.
"Agnostic" means either "doesn't claim to know whether a god or gods exist" or "claims that whether a god or gods exist is unknowable". Or, occasionally and when it's clear from context, "doesn't claim to know whether some particular other thing is true or not". ("I'm agnostic about whether there will be human-level AI within fifty years", for instance.)
Someone who believes in a god or gods is not agnostic in any usual sense. (They might be agnostic on particular questions: "I believe there's some sort of god, but I'm agnostic as to whether it's the one believed in by Christians" or whatever.)
Theists are of the opinion that the probability that god exists is likely, in say 50-100%
Agnostics are of the opinion that the probability that god exists is uncertain, in say 33-66%
Atheists are of the opinion that the probability that god exists is unlikely, in say 0-50%
One gotcha is that, if you account for the greater number of theists, the distribution is not symmetric. Atheists tend to be less certain (more agnostic) than theists.
I would hope the same is true or the atheist/agnostic.
Edit: I was considering the Christian theist.
Theism is belief in god. Atheism is lack thereof. Agnostics claim that gods' existence is unknowable.
To co-opt Gervais' skiing simile: we have people who go skiing, those who do not, and then people who maintain it's impossible to know whether skiing actually occurs.
http://en.wikipedia.org/wiki/Atheism#Definitions_and_distinc...
Looks like my understanding was of "Strong Atheism", while the one Gervais describes would be "Weak Atheism".
I think the "not skiing"-style example is very illustrative of the actual mental model atheists have, and importantly works relatively well in most languages to explain the concept of lack of belief which the "opponent" — someone espousing a belief — has a hard time understanding.
So most atheists don't really insist that a god cannot possibly exist, merely that one doesn't according to available evidence, and as such can and should be ignored. Exactly in the same way I do not take into account leprechauns when making decisions, they are a non-factor.
Edit: mind, I do agree there are some quite argumentative and belligerent atheists.
I would call myself an agnostic atheist. I don't believe in gods, but I have to admit there's no way to prove they don't exist.
I've met people who consider themselves agnostic theists--they think a god probably exists but they admit they cannot prove it.
In the face of confidently presented misinformation, I think it's reasonable to begin with something that indicates that I'm offering a correction and not merely a disagreement. Even if that comes across as less than perfectly polite: correcting someone isn't a perfectly polite thing to do.
(Of course, it really is rude to present something as a correction rather than a disagreement if you're not actually right. So I wouldn't do it if I weren't very confident that GrandMasterBirt is all wrong about what "agnostic" means. And I'll look very silly if it turns out that I'm the one who's wrong. But I am, and he is, and I'm not.)
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When disagreeing, please reply to the argument instead of calling names. E.g. "That is an idiotic thing to say; 1 + 1 is 2, not 3" can be shortened to "1 + 1 is 2, not 3."
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"Uh, no." IMHO carries a different connotation than, for example, "Actually." I think the former is very much like "That's idiotic" and the latter comes off as more polite.
It might be because I hung out with too many Liberal Arts students (who subsist on Pabst Blue Ribbon and sarcasm), but when I read "Uh, no." I hear it in the condescending tone that announces "You are so lamentably incorrect that I have to say 'Uhhhh...' just to give myself time to process how wrong you are."
I suppose I am defeating my own point, because you can also say "Actually" in the exact same tone. But, I feel like it's almost impossible to say "Uh, no." without the corresponding condescension. The "Uh" is very powerful; moreso in text! Because it means not only did you have that moment of cognitive dissonance--the "Uhh" moment in which you process the depth of their wrongness--but that you are also announcing that dissonance to your conversational partner. That, I think, is where the perceived rudeness comes in.
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Also, I understand what you mean about degrees of certainty, but it's important to remember that you could still be wrong no matter how certain you are. That doesn't mean you should eschew presenting or advertising your well-researched beliefs; just that there are ways to communicate them without presenting them as the certainties you (perhaps wrongfully) assume they are.
Interestingly, they aren't mutually exclusive categories. One can easily believe something without claiming to know it, so one can be an agnostic theist, but one can also be an agnostic atheist.
By sheer definition, "agnostic" doesn't really mean anything. But in a social context, it's generally a term used by weak atheists to emphasize they are open minded people who aren't coming to a firm decision either way without evidence.
Here there comes a practical question which has often troubled me. Whenever I go into a foreign country or a prison or any similar place they always ask me what is my religion.
I never know whether I should say "Agnostic" or whether I should say "Atheist". It is a very difficult question and I daresay that some of you have been troubled by it. As a philosopher, if I were speaking to a purely philosophic audience I should say that I ought to describe myself as an Agnostic, because I do not think that there is a conclusive argument by which one prove that there is not a God.
On the other hand, if I am to convey the right impression to the ordinary man in the street I think I ought to say that I am an Atheist, because when I say that I cannot prove that there is not a God, I ought to add equally that I cannot prove that there are not the Homeric gods.
None of us would seriously consider the possibility that all the gods of homer really exist, and yet if you were to set to work to give a logical demonstration that Zeus, Hera, Poseidon, and the rest of them did not exist you would find it an awful job. You could not get such proof.
Therefore, in regard to the Olympic gods, speaking to a purely philosophical audience, I would say that I am an Agnostic. But speaking popularly, I think that all of us would say in regard to those gods that we were Atheists. In regard to the Christian God, I should, I think, take exactly the same line.