Igtheism and Ig-belief
I like the term “igtheism”. It means an atheist position not so much based on the rejection of the idea of gods, or an absence of belief in gods, but atheism because theism is not a clear enough position for anyone to reasonably discuss: theism is a mish-mash of incoherent and incompatible beliefs and wishes. There's a counterpart in religion: ig-belief. I'll explain what it is in a while.
Not being sure what god actually can be does not mean that we can't consider some of the supposed attributes of a god, and so get a clear idea of what a god is not.
Gods aren't just powerful beings, not even powerful beings who can do magic. Being a creator of a world isn't enough, and neither is being the creator of a universe: some being in another universe who presses the “start” button on some super-LHC designed to fiddle about with spacetime in a way that buds off another universe does not qualify. Neither does some sorcerer whose incantation has the same result. Gods aren't aliens who have power beyond our imagining, not even aliens who may run a simulated universe within which conscious beings live.
Gods are supposedly personifications of aspects of Nature; sun gods, moon goddesses, gods of storms and thunder, gods of seas and oceans. The God of Abraham is all such gods merged into one single foundation of reality. God is the basis of all reality (whatever that means – one reason for igtheism). He isn't just moral, he is the essence of morality, somehow excreting moral standards into the universe (more igtheist support). He is (mysteriously) beyond all space and time, and yet somehow manages to find the time to create a universe and and keep track of sins. He can also forgive sins, not just say that they don't matter - his foundation-of-reality status means that when a sin is forgiven, that's really it!
Such a god is as far from a super-alien as we are, as such a god has infinite attributes. God doesn't live within Nature, God is the basis of Nature. No matter how powerful an civilization may become in the history of a universe, it's nowhere near being the God of Abraham, the father of Jesus, the God followed by Mohammed. That's why any alien technological explanation of anything is preferable to theism, because it would be a finite explanation, not an infinite one. As the philosopher David Hume would have said, it would be the lesser miracle.
So I don't accept that it is sensible to suggest there can be evidence for God. This may sound rather extreme, it may sound intolerant, but it really isn't – it's reasonable. It's not just reasonable because the nature of God that we come across in most debates is infinitely beyond any other explanation for any observed phenomena, it's also reasonable because of the game that theists have been playing for a long time, a game which involves the construction of ig-belief – belief based on ignorance of the deity.
It's not atheists who changed the goalposts to reject the idea of God being testable, it has been believers. How often do we hear that God is “beyond our understanding”? That we can only approach God through faith? That it's positively rude to subject religious belief to even the mildest of questions? God is beyond our understanding because he has to be to survive. Things within the reach of our understanding lose their super-naturalness and become first merely interesting and then mundane. How often do we find flying at close to the speed of sound miles in the air boring, an act that would certainly be consider magic a thousand years ago?
Ig-belief is belief in a deity that has been deliberately designed so as to not be vulnerable to reason and evidence – a deity of which believers are necessarily ignorant, one beyond our ability to understand, with his “mysterious ways”. What I am saying when I suggest zero-intellectual-tolerance of the idea of God is that it's time to stop giving credibility to this game of believers. If a religion wants to come up with the idea of a testable God, which would involve throwing out the infinite attributes, the supernaturalism, the promises of eternity, then fine. But we have had centuries of goalpost moving. We should say “enough”.