Of course we can. And in fact it is assumed already that they don't exist.
This is false.
Bigfoot spotters believe he exists, they don't assume he doesn't exist.
Alien abductees believe such aliens are real and abduct people, they don't assume they don't exist.
Those who don't believe such claims indeed assume they don't exist. This for all practical intents and purposes. And atheists do the same with gods.
This is not a problem. It is a practical
necessity.
Don't you assume that all the gods you do not believe in do not exist for all practical intents and purposes?
I submit that you do. Are you, for example, worried at all that you might not go to whalhalla if you don't die on the battlefield with an axe in your hand?
Off course not. Can you prove there's no whalhalla? No, you can't.
The simple fact is that if you are going to "not" assume all unfalsifiable things you don't believe to be real to not be real, you will simply not be able to function properly in reality. You won't even be able to cross the streets because an invisible truck you can't prove doesn't exist might run you over.
All this comes down to one simple thing that all of us do out of practical necessity:
Non-existence is assumed until existence is sufficiently demonstrated / believed
We can point to the fact that they do not exist within the description and field of inquiry proposed. We can't do that with "God", which is why those who want to argue that God does not to exist like to replace it with these false equivalents.
I have just explained above how this is not true.
I view and treat the non-existence of bigfoot and alien abductions in the exact same way as the non-existence of gods.
And I have just explained why.
And I will once more reiterate that you do the exact same thing with all gods you don't believe in also.
We do this, out of practical necessity.
We can't prove anything absolutely. But that isn't the goal. The goal is to win the argument against God existing.
I have no need for such an argument. I just respond to those who claim a god DOES exist.
And if there are no people claiming a god (or bigfoot or alien abductions or....) DOES exist, then I have no reason at all to even talk or think about it.
And when the atheist can't do that directly, he likes to replace God with a false equivalent that he believes has already been proven not to exist.
This is a strawman once again.
I don't think bigfoot or alien abductions have been proven to not exist. In fact, I will flat out state that it is
impossible to do that.
The reason I bring them up, is because the person arguing for a god will likely not believe in bigfoots or aliens and thus, for the practical reasons explained above, assume they aren't real either.
And I do this to make them undestand my reasoning. Because the reasons I assume no gods exist / do not believe gods exist
are the exact same reasons of why you likely don't believe bigfoots / aliens exist or
assume they don't exist.
You don't KNOW they don't exist. You assume they don't. Huge difference.