Neither.
Personally, I wouldn’t say they have a ‘soul’ to begin with, because it lends itself to this kind of confusion. But the thing I take you to be pointing to when you say ‘soul’, I would call something like ‘mind’, ‘consciousness’, or ‘person’. And when you cut someone in half, you destroy the brain, and so by definition you destroy the mind/consciousness/person. Even if these half-bodies could survive, their minds would be completely different from the mind that existed prior to being cut in half.
Language fails us in this area, because we’re talking about things that it’s hard to point to specifically. Maybe a better word for what I mean would be ‘personality’: major changes to the brain often completely change a person’s personality, and the former personality doesn’t go anywhere, any more than a pattern of shapes goes anywhere when we rearrange them.
These are very different claims, but it’s worth considering them together.
First, ‘measure’ here is a bit unclear. I am using the term quite broadly, to refer to all forms of empirical observation. So something like a doctor interviewing a patient is a kind of ‘measuring’.
And in that sense, we can and do measure various aspects of consciousness. That’s how we can confidently say that a chair is not conscious and a person is, or with less confidence that a person is conscious or unconscious in a given moment. It’s how we know that locked-in syndrome is different from a coma.
It’s also why we have trouble clearly dividing animals into conscious and not-conscious, and why there is a lively philosophical debate of whether modern LLMs are conscious: the observations we use to establish consciousness are inconsistent as applied to those entities, so the result isn’t clear.
I’m not trying to suggest that there is a computer screen in the brain, but that the way a person speaks and acts are a product of the functioning of their brain just as the display on a computer is a product of the functioning of the computer.
I think there are good reasons to reject p-zombies (what I think you mean by ‘npcs’), and good reasons not to worry about solipsism. But hose conversations can’t get off the ground until we’re clear on what we’re talking about here.
I agree the Turing Test is outdated, that’s been clear since ELIZA. But it’s not entirely without merit – it seems to capture something about what we’re actually referring to when we talk about consciousness (and a lot of people really do attribute consciousness to anything that can pass it).
But, how does the concept of a ‘soul’ avoid this problem? How do we determine e.g. if animals have souls?
Interesting. What specifically? This seems like a pretty vanilla take on consciousness from a scientific materialist perspective. And it doesn’t look like we have much disagreement on how consciousness works.
Or was this meant as a reply to FutureOne?
I’ve never heard of this specific to split-brain patients, but I found papers discussing lateral specialization and religion, e.g. one from 2019 (abstract, sci-hub) that claims, “A consensus is emerging from the literature that religious experience tends to be associated with the
right hemisphere.”
And it doesn’t seem outside of the realm of possibility based on what I do know about split-brain patients, e.g. that one hemisphere can do simple math while the other can’t (95% correct vs. 58% correct) see ‘Patient JW’ on the split-brain wiki page).
Lateral specialization in general is well established, and anything that is laterally specialized before the corpus callosum is cut will lead to measurable differences between the hemispheres after it’s cut.
