Read part one, here.
I've said before that absence of evidence is evidence of absence, but I want to expand on that a bit.
Once I decided to make a sandwich. As is my wont, I mused quietly to myself whilst I pulled items off of shelves and out of the fridge. I grabbed my bread, my turkey, my cheese, my mustard, and where the fuck is my mayonnaise? My mayo's gone! I just bought some at the grocery store yesterday! I checked the fridge again. No mayo. I checked a third time, carefully perusing the mostly empty shelves. No mayo. For about five seconds, I briefly considered the possibility that someone had broken into my apartment for the sole purpose of stealing my mayonnaise; a brief checked showed me that, yes, my TV and video games and whatnot were still there so that notion was beyond absurd. I turned and looked again and, it's a miracle! My mayo was sitting on the counter next to the mustard. I'd already gotten it out of the fridge and hadn't really noticed because when I talk to myself I tend to not pay attention to what I'm doing. This is how I've occasionally gotten lost on the way to the bathroom or driven to the wrong campus on my way to work.
No one, on hearing that story, would find it reasonable to ask, "But how did you know the mayonnaise wasn't in the refrigerator? Just because light failed to reflect off of a jar of mayonnaise and impinge on the cones and rods on the back of your eye doesn't mean that there wasn't any mayo in the fridge! Absence of evidence isn't evidence of absence, after all!" Unless, of course, they were philosophy majors. Twenty-year-old jackasses love to say things like that, mostly because they don't know how ignorant they are.
But the absence of evidence for something can be evidence against it. When you're talking about the abstruse realm of particle physics, in which you have to accelerate things nearly to the speed of light and smash them against each other and pick up the pieces (a method unfairly compared to hitting a watch with a hammer to learn how it's put together), not finding a particle doesn't mean it doesn't exist; unless you designed your experiment such that it would be unreasonable for it not to show up. When you're talking about a jar of mayo, arguing that just because you didn't see it doesn't mean it wasn't there is just fatuous. I didn't see it in the fridge because it was on the counter.
So, what about god? I've already discussed why I dismiss the purported evidence (miracles, scripture, revelation) in favor of the god hypothesis. Most everyone who says they don't believe in god state that they lack belief because they haven't seen any evidence. It bothers me that they then go on to refuse to say the believe there is no god (the two aren't equivalent positions) because they claim science can't talk about god. Then why the hell don't you believe? Agnosticism because of a lack of evidence is a scientific position; it's the default scientific position. Why, then, do I go on from there to say that I believe there is no god? What is my evidence in the other direction? I feel that the god hypothesis, if true, would have a measurable impact on observable reality and the lack of that evidence is a compelling argument against the hypothesis.
For example, scripture. I've already stated that if there were a deity, there wouldn't be many mutually exclusive scriptures. There would be one, it would be definitely accurate and demonstrable true. It wouldn't contradict itself and there would be no pretenders purporting to give an alternative truth. A deity so moved as to provide a scripture would also be able to censor false competitors. The celestial dictatorship would have no trouble silencing opposition or critics.
Revelation, miracles, and scriptures, in the face of a true god hypothesis, would be so evidently and clearly true that there wouldn't be the need for the fatuous notion of faith. It wouldn't be received truth but perceived truth. I reject the god hypothesis as firmly as I reject the invisible jar of mayonnaise and as I immediately rejected the notion that someone had broken in and stolen my mayonnaise; the lack of evidence was obviously evidence against the hypothesis. I don't believe, at all, because when the universe is presented with the question, "Is there a god?" the response is a deafening silence.
Next: What would it take for me to believe?