So when they say "ghosts" are they talking about souls?
What do you believe qualifies as a soul OP?
I have a better question: How is she when she doesn't surf?
Why do we not have an anime about cute skeletons doing cute things?
Nah, it's a bit more complicated. Basically, a ghost is the bare minimum stuff (physical or non-physical, though one of the main themes in GitS is that it's completely physical) that's required to make something conscious.
It's more your conscious than your soul