Colloquially, yes, "I don't know," is a fine answer. But more formally, it doesn't answer the question about belief. My main objection to you is that the colloquial conflation between knowledge and belief forces you to misrepresent the position of atheism in practice. This is why I'm pushing so hard about using my definition. It's not so much the label I care about, but the misrepresentation of the people who identify as atheists.

Let's use an analogy. If I had a completely fair coin and I asked you, "Do you believe the next flip will be heads," the formal logical answer should be no. That doesn't mean you subscribe to the belief that it will be tails. You can abstain from believing it will be either one of those outcomes while knowing full well that it must be one of those two outcomes. And abstaining from believing in either one of those outcomes is the logical choice since there is no reason to believe it will be either one of those outcomes: the chance is purely 50-50. To bring this analogy back to the topic at hand, theism is a belief in God. Based on the prefix, atheism is then a lack of belief in God. This ranges from an abstinence from belief, to actively disbelieving in God.

Again, I know this is not how we speak colloquially, but formally my reasoning above is correct. And the reason I insist on being so formal about this regarding atheism is because without recognizing what we mean by atheist, we risk ascribing them beliefs and positions that are unfair, and that they don't subscribe to. That has happened here, and in the other thread in the flame forum. With that in mind, clarification seems important.

You're right, there is no single person who makes these definitions. However, what I'm saying in practice is true. The people who identify as atheists are not making a claim about knowledge, they are making a claim about belief. Atheists would welcome anyone who doesn't believe in God into our ranks, including those who are 50-50.

When you look at the various atheist groups that have sprouted up in the last ten years, we have a whole range of people that join. There are plenty of people that join that are put off by the forcefulness of the church, yet are unsure about whether they believe or not. They're often merely looking for a secular social group to replace the function church served. Then there are others, such as myself, who would be more like 99-1 regarding belief in God, and then there are those in between and beyond. However, to date, I don’t think I have met anyone who claims to be certain that God doesn’t exist.

So with regards to having such a diverse membership, your definition of atheist just doesn't fit. It's not about some authority that defines those words, it's about how well those words fit. And yours simply doesn't fit.

I agree! What you mean precisely by a word is not important as long as you're not using that word to mischaracterize people. So as long as we can agree on what self-identified atheists are and are not in practice, let's put this relatively meaningless squabble about definitions behind us and focus on the crux of the argument.

The problem, again, D3V, lies with definitions. On the one hand, you're using the word "know" in an epistemological sense, and other hand you're using it in the colloquial sense. In the epistemological sense, can you truly know anything about the real world? In the epistemological sense, science doesn't prove anything. In the epistemological sense, even your senses don't prove anything about the external world. What if I'm a brain in a vat. What if solipsism is the true description of reality? The epistemological answer to, "Do we know anything?" is easy. No. However, while these questions are interesting to ponder, they don't really lead anywhere.

To operate on a day-to-day basis we make the simplifying assumption that what we perceive is real. When we talk about what we know, we talk about it under that assumption. You might think that we're nothing more than a brain in a vat, but I know you look both ways before you cross the street. For all practical purposes, everyone bases their thoughts and actions on this assumption.

This simplifying assumption goes beyond just how we operate in day-to-day life, though. It is an assumption that underlies all of science. And science has told us a lot about the external world, with tangible results. For instance, the idea behind the big bang is the same idea that underlies our GPS satellites. If the big bang turns out to be faulty in any significant way, then the fact that our satellites stay in orbit is mere serendipity. We would have no way of explaining how they stay in orbit. Virtually every technological advancement in our society is intertwined with some fundamental underlying scientific principle in a similar way. And we were capable of developing all of this science because of the simplifying assumption. If we tried to explain observations regarding the external world through metaphysical hyperrealities the human race would be perpetually stuck in its infancy.

The point in all this is that people, and the human race as a whole, operate under this simplifying assumption for everything except when it comes to God. This is quintessential special pleading. If you make this exception for God, then you can make the exact same argument for any mythical creature or object you want. Fairies? They might exist in a realm beyond our understanding. Thor's hammer? Same thing. Since it's in a realm beyond our understanding it's inherently unknowable. Are you really prepared to admit to these things have a 50% chance of being possible to remain consistent in your beliefs? If not, but you're willing to make an exception for God to be 50-50 because he exists in some kind of metaphysical hyperreality you have to at least be able to explain why you don't make the same exception for other things.

Let's briefly consider a hyperreality that we know exists: our minds. We can imagine things. We can even do this subconsciously as dreams. We know dreams exist. However, we don't consider the objects or situations we encounter in our dreams real in any way, because those objects or situations don't interact with the physical world in any way. So even though we have a hyperreality that most people experience, we don't consider its content real because it doesn't interact with the physical world beyond what goes on in our thoughts. To be consistent with this, we should not consider the contents of any hyperreality real unless it at least interacts with the physical world in some way. So to be consistent in what we consider real or not, if God is real he should have interacted with our physical universe in some way at some point in time.

I usually state this intuitively: We can play the what-if game all day, so let's not consider anything real unless it conforms to our simplifying assumption. Postulating something imperceptible to the entire universe does not further our understanding about anything in any way. That said, I think the above paragraph provides a concrete example about why we should think this way. People don't consider anything real unless it interacts with the physical world in practice, and to demand anything less for God to be considered real is special pleading. And since the reality of God is now judged, as it ought to be, by the standard of interacting with our world, Russell's teapot still applies. So I once again pose the following question to you: since you admit that there is no evidence for God, why should a lack of evidence for God not demand disbelief when the same lack of evidence demands disbelief in Russell's teapot. Or do you truly believe that it is possible that there is a cosmic teapot floating around somewhere out there simply because we haven’t been able to disprove it?

Let's change directions and discuss probabilities briefly. Without any a priori knowledge about a probability distribution, all possible outcomes to an experiment must be considered equally likely. I could pose the question to you, "what is the probability that I will roll a six on a six-sided die?" If you answer that, “well, you can either roll a six or something else, therefore the chance is one-half,” this is obviously faulty reasoning. You have to consider all the possibilities, and they ought to be weighted equally. Now if it turns out that the die was loaded, we could experimentally determine this and adjust the probability distribution as needed, but it would not make sense to assume the die was loaded. Before performing any measurements, the logical answer to, “what is the probability that I will roll a six,” is one-sixth.

Again, let’s bring this analogy back to the topic at hand. For the following paragraph I will define God as simply and with as few strings attached as possible: a sentient being that created the universe. We can ask the question, “what is the probability that a hyperreality with God in it is real?” It is obvious that the creation of the universe must be logically consistent as it involves the physical universe. Therefore, two hyperrealities that offer contradictory accounts of the creation of the universe cannot coexist.

I can think of multiple possible ways the universe was created. Perhaps our universe stems from something akin to mitotic division from a parent universe. Perhaps our universe is what’s beyond the event horizon in another universe. Perhaps the universe stems from fluctuating quantum fields. The point in all this is that there are a myriad, perhaps an infinitude, of conceivable ways that the universe could have come into existence. The subset of such hyperrealities containing a God would therefore be infinitesimally small. Now when we talk about believing in any particular one of these hyperrealities, we are talking about a human concept: belief. And belief is intrinsically related to what we consider probable. But based on our discussion before, unless we have a priori knowledge about our observations we should assume all possible outcomes evenly likely. As you’ve said, we have no knowledge about hyperrealities. Therefore, believing in one over the other simply does not make sense. If you choose to believe in one particular hyperreality you must justify that belief, otherwise this is special pleading. This is why the atheistic position, even the 99-1 atheistic position makes more sense than the theistic position.

To summarize, when we discuss hyperrealities we simply don’t know which is correct. Therefore, it doesn’t make sense to prefer one over the other, given the myriad of potential hyperrealities consistent with the creation of our universe. Furthermore, when we talk about what is real and what is not, or what we know and what we don’t we make the simplifying assumption that what we perceive is real. Even if we choose to prefer one hyperreality over another, it makes no sense to define its contents as real unless they interact with our perceivable universe somehow. I have shown this by analogy to dreams: they are a distinct, real hyperreality, yet it makes no sense to consider their contents real as they don’t interact with our physical world. Therefore, for any hyperreality to be considered real they should interact with out physical universe at least more than dreams do. And if they interact with our physical world then those interactions are in principle testable by science. Let’s turn to that.

Now we’re getting somewhere. You favor a hyperreality explanation, particularly the God explanation, because you think our universe is not self-explanatory. You must realize that this is a God of the gaps argument. Historically, such justification of God has shrunk, and by all signs will continue to do so. People used to not be able to explain lightning, therefore Zeus must have done it. People couldn’t explain life, therefore God must have done it. Now that we’re close to being able to explain life, it’s shifted to we people can’t (allegedly) explain the universe, therefore God must have done it. What if one day we can explain the beginning of the universe? What if one day we can show that the universe could have come about from purely physical principles? Would you be willing to abandon the God, and any other hyperreality explanation then? You should, because thus far this is the only justification you’ve offered in it making sense to believe in something as grandiose as a hyperreality without any evidence in favor of it.

That said, we do have purely physical explanations for the beginning of the universe consistent with what we know about it without having to postulate any hyperreality. Mass-energy cannot be created or destroyed beyond the Heisenberg uncertainty principle. Recognize that at its heart this is a mathematically precise statement, and there are times when it will be inconsistent with your intuition about what conservation of mass-energy means. We have shown that matter, along with everything else in the universe, can come out of seemingly nothing through changes in the configuration of quantum fields. These fields fluctuate spontaneously between configurations, corresponding to the appearance and disappearance of particle-pairs as long as they obey the Heisenberg uncertainty principle. The Heisenberg uncertainty principle states that if a field fluctuation changes the energy of the configuration considerably, then the time that the fluctuation lasts is short. Conversely, if the fluctuation changes the energy very little then the time of that fluctuation can be long. The vacuum state of the quantum fields is one where there are no particles. What if there was a quantum fluctuation that created particles, however did not change the energy at all. Such a fluctuation could last for an arbitrarily long time. Our universe could be such a fluctuation, considering that gravitational energy is negative and therefore it is very possible that if we add all the positive energy in the universe with the negative energy it may very well sum to zero. This is a plausible explanation for the appearance of our universe consistent with what we know about it.

The difference is that militant Muslims fly planes into building, militant Christians bomb abortion clinics, whereas militant atheists argue with you on the internet. If we could get people away from religious violence and stop religion from corrupting our education system, I’m pretty sure atheists wouldn’t care what silly things people chose to believe.

So thus far, I have agreed to stop debating the definition of atheist as long as you stop mischaracterizing what atheists believe in practice. I have shown that any particular hyperreality is as unlikely as any other one, so it makes no sense to actively believe in a hyperreality with God. I have shown that real must be defined as something that interacts with our physical world, so any hyperreality that exists ought to have this property. For God to be real, he must have at some point in time interacted with our world, and therefore his existence can be discussed using logic and reason. I have then shown a plausible way that the universe could have come into existence without postulating any hyperreality at all. Given all this, I simply can’t see how you can assert that the existence of God is just as likely as his nonexistence.