Re: Christianity
I see what you're saying, but the difference is that I don't assume there is no God. You don't assume something when there is no evidence either way. Do I think it's more likely that there isn't a God? Yes. However, I do not deny the possibility.
You're making several important mistakes here. First is the assumption that the nonexistence of god requires proof. This is nonsense; you cannot prove that something doesn't exist. The burden of proof is on those who claim god
does exist. Saying "there's no evidence either way" is nonsensical, because atheism isn't based on the fact that there is evidence proving god doesn't exist - it is based on the fact that there is no evidence proving he
does exist. Atheism takes the default and most logical position, i.e. that it is ridiculous to assume something
does exist when there is absolutely no evidence to support this claim.
The second mistake is that you think atheists deny the possibility of god's existence. We (or at least I) don't. Being an atheist says nothing about whether or not I think god
might exist - all it says is that I, personally, have no reason to think he does. I am perfectly aware of the fact that there is a
possibility of god's existence, I just happen to think that possibility is extremely unlikely.
Now I'd like to challenge your claim that you don't assume god exists or doesn't exist. In theory this is all very well and good, but in practice I think you'll find you do, actually, assume god doesn't exist. This is similar to the point that agnosticism (as it is so unfortunately misconceived) is actually atheism. Let's try break it down:
1. You don't assume one way or the other about the question of god's existence.
2. Therefore you do not assume god exists.
3. Therefore you do not lead your life in line with the belief of god's existence.
4. Therefore you do not have a belief in god.
5. Therefore you are an atheist.
I would argue that
any position apart from a straight forward, unequivocal "god exists" is atheism. What I'm trying to say is, all the objections you're raising - they're not objections. No atheist denies the possibility that god exists. You say you don't make assumptions - by the simple act of not assuming god exists (and I'm guessing you don't, since you haven't mentioned observing any religious practices etc.) you are assuming he doesn't. Because otherwise you
would observe religious practices. You see what I'm saying? If you assume god exists, there are certain things you have to do - rules to live by, that sort of thing - but if you assume he doesn't, you don't have to do anything special. It's not like you have to go and follow rules of atheism; simply by not assuming god exists, you are assuming he doesn't.
Atheism is by no means one end of the scale; it is not an equivalent to theism. It is the absence of theism. That is all, pure and simple; unless you believe in a god, you are an atheist.