If I point to something and say “that’s Manganorama, and Manganorama is orange and fearsome”, I could be doing two things.
a) On the one hand, I might be defining Manganorama as being (among other things), orange and fearsome, and then moreover applying the concept so defined to ‘that’. If someone disagreed, the natural thing for them to say would be ‘that’s not Manganorama, because it’s not orange and fearsome’.
Moreover, if they thought that nothing in the world was both orange and fearsome, they might say “Manganorama doesn’t exist”, or “there is no Manganorama”.
b) On the other hand, I might be fixing the word ‘Manganorama’ not to a definition but to ‘that’, and then moreover observing that it was orange and fearsome. If someone disagreed, the natural thing to say would be “Mangorama is not orange” or “Mangorama is not fearsome”.
In the two cases I’m really conveying almost exactly the same information: I think ‘that’ is fearsome and orange. But I make use of a certain word in different ways.
And the appropriate way of disagreeing with a) would be entirely absurd if I had meant b) – because if I point and something and name it ‘Manganorama’, then just about the only thing we can be sure of is that Manganorama exists. Someone saying ‘there is no such thing as Manganorama’ would be saying something like ‘this thing here doesn’t exist’.
Conversely, the appropriate way of disagreeing with b) would be to say that ‘Manganorama is not orange and fearsome’ – but if a) was meant, then it is the definition of Manganorama to be orange and fearsome, and so that claim is like saying ‘cats are not feline’.
What if I said it without definitely committing myself to one meaning or the other? Then I could respond to any disagreement by making it appear absurd and self-contradictory. This might be quite convenient – indeed I might well mistake this bit of ambiguity for self-evidence.
Now compare this with the word ‘God’. If someone says ‘God, who produced the world, and who everything depends upon to exist, is supremely wise and just’, is this meant more like a) or more like b)?
If it’s like a), and the word ‘God’ is being defined by His supreme wisdom and justice, then the appropriate way to disagree is to say ‘there is no God’, meaning ‘there is no supremely wise and just being, and certainly no such being produced the world’.
Whereas if it’s like b), and the phrase ‘God produced the world and everything depends on God’ functions like pointing, to fix what the word ‘God’ is to refer to (namely, the ultimate source and foundation of everything that exists, i.e. of all this stuff around us here) then the appropriate way to disagree is to say ‘God is neither wise nor just’.
The former is the more common thing to say – but sometimes one finds theists protesting that God’s existence is undeniable, a fact as obvious and self-evident as 2+5=7. Which it is – if ‘God’ designates simply ‘the ultimate source and foundation of everything that exists’. For there must be some such thing, even if it is simply ‘everything that exists’.
On the other hand, if one accepts this and says ‘God exists, but is simply a material being’, or ‘God is spacetime’ or something like that – one is open to the objection that this seems to make a mockery of the definition of God. God is defined, for instance, as wise and just, and spacetime is neither.
Do I have a point? One point is just a (fairly common) criticism of a lot of theistic argument strategies (like ‘first-cause’ arguments). But those strategies aren’t even seen around very often any more, I think.
So really the point is to observe that what is really the same debate could either take the form of “God exists and is just” vs. “God doesn’t exist”, or “God exists and is just” vs. “God is indifferent to your petty morality”.
Moreover, one might take the position of ‘atheism’ while not only saying ‘God exists’ but also agreeing with many of the arguments that theistic philosophers made about God – such as that God cannot have parts, strictly speaking (which means that if God is spacetime, then spacetime must be wholly indivisible – is that coherent?). Or that God is beyond time, or infinite (what would that imply – if anything?)
But most of the time of course people are too busy shouting and burning stuff…