A "meta-argument" against all future arguments for God's existence ?

[emjay]

What do you consider the soul to be?

The standard meaning of "soul" in Western philosophy was defined by Aristotle and adopted later by the Christian church. For them, it has a specific meaning. Obviously you're free to define it however you like, but then you'd be talking about something different.

For Aristotle and for Christians, the soul is the form of the body. "Form" here doesn't mean just "shape," because a newly-dead body has the same shape but no soul. As always in Aristotelian hylomorphism, "form" refers to the shape of the parts, their function and interaction. How they work, what they do. 

Souls always give form to matter. The matter of the body is carbon, calcium, hydrogen, etc. The way this matter is put together, to make it into the unique thing that it is, is the form -- the soul. 

Therefore souls are not material, but always exist with matter. Matter always has a form, form can't exist without matter. 

This is why Paul doesn't say that after death the soul will fly away immaterially. He says that the same soul will go to new matter. This is the part of Christianity that demands supernatural belief. We can all agree that bodies have forms, but not that the same form can somehow go to new matter. Aristotle didn't think this was possible, either. 

And if you don’t like the word “soul”, just replace it with the word consciousness. Where does consciousness come from?

Again, if you choose to say that "soul" and "consciousness" are synonymous, no one will stop you.

Traditionally, however, consciousness is one of the activities of the body made possible by the fact that the body is put together in a certain way -- the form, the soul. Soul is responsible for more than consciousness, however. It's also responsible for all the unconscious processes, and everything that makes a person a person.

This is very interesting. I've largely forgotten what Aristotle had to say about it but was it 'the form of living matter'? Ie under that conception there can never be matter without form, so soul is the special case that is the form of living matter? As opposed to an unnamed case of 'form' for any inanimate matter, including dead matter? If so I did wonder at the time while reading that how you'd get from that to a migrating soul, so interesting to see you explicitly state that Aristotle think didn't that was possible and Paul did.

My dad as a Christian doesn't think the soul is consciousness per se either, though it's hard to pin down exactly what he does think, though I don't think it's the Aristotlian conception, or at least not attributed to him if it is that or something like that. He also distinguishes a spirit as something different from a soul, and equally essential to life, but to me they're both just different ways of adding nothing to the equation, seemingly largely borne out of the view of living matter being fundamentally different from non-living matter - when to me there's no fundamental difference, just ultimately chemistry and physics at play in either case - but where that sort of 'life force' idea is most clearly exemplified by Aristotle's concept of a soul. I guess all those ideas stemmed from that concept, but I didn't know/infer that until I started reading Aristotle.

Don't get me wrong, I think there is a nice simplicity about Aristotle's view of a soul, a useful special-case designation of the same matter/form distinction he makes for everything else... it just fits nicely within that existing system of thought without really changing anything... and to the extent that I'm willing to entertain Aristotle's perspective on the world, ie for the sake of argument, then I'm willing to accept that rather mundane concept of a soul, but that's still a far cry I think from the migrating soul that you say Paul envisaged.