You say the premise that 'there can't be an infinite series of past causes' is a false premise (in other words, that there can be an infinite series of past causes). I would say that this would be true if time itself had no beginning. There could be an infinite series of past causes, if there was an infinite amount of time for these causes to have happened in. But if matter and energy began to exist, then time itself began to exist, since science has proven that time is relative to matter and energy. Before matter and energy existed, time did not exist. So before time existed, there could not have been any series of past causes at all.
Science convinced me that both the universe and time itself began to exist. To believe that it began to exist without a cause makes no sense. If nothing, not time, matter, or energy, existed at one point, what would cause it all to suddenly come into existence? I would perhaps agree that quantum mechanics is doing a decent job at explaining the 'how', but what about the 'why'? Did the laws of quantum mechanics create themselves? For quantum mechanics to have created matter and energy out of nothing, something had to have put those laws in place, something outside of nature and time. I confess to having only a layman's understanding of quantum mechanics, but I know that natural laws cannot create themselves out of nothing. To exist, they either have to act on something, or something has to put them in place. Something had to have existed in order for the laws to have taken effect.
So let me see if I understand your theory about why the universe is the way it is. You're saying that at one point, nothing existed, yet there were laws of quantum mechanics which acted on all of the nothingness to create an incredible amount of matter and energy, and that this happened for no particular reason. And, hold on, but do you believe that it created all of this matter and energy to be orderly? Or did it create it all to be disordered, and then order arose out of the disorder due to natural means?
You said, "if we can't come to a rational idea of what he is, then he can't exist because we have no idea what 'he' or 'God' refers to." I'm saying that we can come to a rational idea of what he is, by looking at the universe itself, just as we can make logical conclusions about what a painter is like, by looking at a painting of his.
You said, "What is the supernatural world? Or the nonmaterialistic world? Do we have any clue about what this is? Apparently we think we do. But let's get right down to it. Do we? Well, what sort of evidence do we have for such a world? None that I can think of." We have plenty of evidence, so much evidence that approximately 90% of the people on Earth believe in it. But if you're looking for the evidence exclusively in the natural world, you aren't going to find it, any more than if you look for Bill Clinton exclusively in your closet, you won't find him. The natural world can show us much about the supernatural, just as a painting can show us much about the painter, but if you look for the painter only in the painting itself, you won't find him.
So what do we know? We know that love is good and hate is bad, that life is good and death is bad, that forgiveness is good and condemnation is bad, that God is good and the devil is bad (even those who don't believe God and the devil really exist still understand this concept, at least hypothetically). It's not the natural world that teaches us this, and, contrary to what many might think, neither is it our family or society. There's the idea that children are blank slates, and all of this is taught to them by their parents or society. But don't you agree that if a parent constantly abuses a child, that the child will know that the parent is doing something wrong, even if the parent and/or society never tells the child this? Or that a person living within an evil society will often recognize that there is something evil about the society?
You said, "If God (whatever that is) wants to talk to me, I'm pretty damn certain he'd get through." If you understand the basic concepts of right and wrong, and try to favor right over wrong most of the time, then I'd say God HAS gotten through to you, but that you've attributed His voice to being something else. Think about this: what is the ultimate source that decides right or wrong in us? Would you say that an individual's concept of right or wrong is the highest source? That if someone believes something to be right, then it's right? That something is only wrong if someone believes it is wrong? If so, then should we refuse to jail anyone, no matter how horrible their crime, if they don't feel that they did anything wrong? You might answer no, that society's concept of right and wrong is the highest source. If so, then has everyone who has ever opposed their society been wrong to do so? Is it okay for a society to torture small children if the society believes it's okay? Not only Jesus, but people like Gandhi, Martin Luther King, and Henry David Thoreau have been fully justified in their opposition to societal corruption. I imagine that, to an atheist, it would almost seem like sometimes society's concepts are higher than an individual' concepts, and at other times, the individual's concepts are higher than society's. So who ultimately decides right and wrong? There is a higher understanding of right and wrong that surpasses that of any individual or society, that all of us are ultimately subject to. It's the understanding of right and wrong that God has given to us.
You say, "Many keep claiming God was what created the Big Bang. Wrong. The Big Bang is a theory that encompasses itself. It (by definition) needs no cause. There is simply no role a god would play in the Big Bang. All Christians seem to miss this (except the ones who blindly deny the theory)." Sorry, but either the Big Bang didn't happen, or it had a cause. If it didn't have a cause, it wouldn't have happened. I believe that the Big Bang created energy and matter and time out of nothing. With no matter or energy or time, no natural forces or quantum mechanics would be able to act on the nothingness by themselves. Without something interfering, it would have stayed nothing, and nothing would currently exist. Yet something turned that nothing into something (an awfully big and complex something, for that matter). Whatever this cause was, it could not be a natural force (since nature didn't exist until after the event happened), it could not be a force subject to time (since time also did not exist until after), it could not be a non-creative force (since it created), and it could not be an unintelligent force (since what it created was complex at creation, or was set up to become complex over time). So I'm saying that we can know that the creator is supernatural, timeless, creative, and intelligent. You keep saying that we can know nothing about this creator, but have yet to respond to this argument.
To credit quantum mathematics is to credit the process of creation rather than the creator. It's a little like crediting a great novel to the author's typewriter or word processor, rather than to the author himself.
How I came to believe in God is kind of a long story, but here's the short version. I used to be an atheist, and I studied all of the concepts of how our universe got to be like it is. Then I looked up at the sky one night, and asked myself if it really made sense that all of this happened by chance and natural laws alone, and found that I no longer had enough faith to answer 'yes' to that question. I don't believe it's even possible for it to have happened without a purpose, and even if it is possible, the chance of nature somehow creating matter out of nothing, and then organizing it to such a degree that life could survive and thrive for billions of years, is, at best, somewhere around one out of trillions and trillions. You would probably argue that I 'invoked God' to explain what I didn't understand, but that's not true (any more than someone 'invokes a painter' to explain how a painting came to be). Logic would tell us that whatever force is responsible for the creation of nature, time, and natural laws would be a supernatural, timeless, creative, intelligent force.
You keep telling me that I need to show what God is. Unless you can either show how my argument (that we can logically conclude that the creator of the universe is supernatural, timeless, creative, and intelligent) is a bad argument, or accept at least this much about Him, then there is really no way our discussion can go any further. If we're going by the original plans, we are now more than half-way through these discussions. I think it's time you respond to my basic premise.