If I’m such an open-minded atheist — if I really am an atheist because I think the God hypothesis is unsupported by the evidence — what evidence for God would I accept? What would it take to change my mind?
I’m going to take a rather different approach: I’m going to tell theists to not bother.
It’s not that I’m unwilling or unable to change my views, or that I think I’m absolutely right about everything (I already know I’m not). Physicists, for instance, frequently explain things to me that make me toss out a lot of preconceptions. It’s just that I know theists are wrong. I’ve been through these arguments many times before, and I know what they’re about, and I know what approaches the true believer will take, and I’m not going to accept any of their arguments, so we might as well not waste time with them.
Basically, I have a set of simple prerequisites that theists can’t meet — their beliefs fundamentally contradict any reasonable expectations. Here’s what I would demand:
They must accept the evidence of the natural world. What that means is that the first thing they have to do is acknowledge the validity of scientific explanations, because they are based on empirical knowledge. You don’t get to advance your hypothesis about how the universe works by throwing out the entire body of accumulated human wisdom!
They have to accept that they don’t know any more than I do about the nature of entities outside this universe. Deities and afterlives and all that crap are outside human experience; you don’t get to sashay in and announce that you personally have direct knowledge of the mind of god that I am not allowed to have. We have to restrict ourselves to information that is universally accessible. Which, of course, means that most theists claims are bogus, because they are unknowable.
They have to recognize that extant religions are all false. We know enough about the history of religion to recognize their idiosyncratic and human origins. If you can see that Scientology and Mormonism are frauds, then you should be able to see that Christianity and Islam are similarly the product of deluded human minds. Don’t waste our time trying to persuade me that debunked beliefs are really true.
They must define their god or supernatural property clearly and unambiguously. Inevitably, every faith-head fails on this criterion: go ahead, try to get a Christian to give a consistent description of Jesus’ role in their life. I guarantee you that every time an atheist tries to pin them down on something concrete, they’ll rapidly fall back on Karen Armstrong-style platitudes, which are all empty noise. “God is Love” is utter bullshit.
I think that even asking for things like miracles and prophecies and consistent holy books and deities manifesting on earth is conceding way too much — it’s treating their claims of the kind of phenomena that would validate their faith as reasonable forms of evidence. They’re not. Those are the things theists tell each other to “prove” their beliefs, and they’re bogus — they’ve never demonstrated anything.
Break the cycle of lies. Stop framing atheist questions in theistic terms.