At 08:07 AM 4/17/99 -0400, John Heritage wrote:
> 1> Does anyone know of a way (ethical or unethical - I'm asking
>purely for knowledge) to "test" and "prove" whether or not
> there is an existance of a soul that "attaches" to the human body
Naturally, there are many different plausible definitions for a soul; you'd have to nail down pretty specifically what you're referring to before you could verify its existence.
However, I think we can do quite a bit in the way of testing for a soul. If you think that the soul is a spiritual thing which can affect the physical world (even if only through our brains) then we should see some repeatable physical phenomena in the brain or elsewhere which can't be explained physically. Any such phenomena would be valid criteria. The absence of such phenomena, would disprove the claim that the soul acts on the physical world, and therefore also disprove the claim that the soul takes any responsibility in shaping our decisions about how to act. (If it did, it would affect how we act.)
What can't be disproved, however, are statements about the soul which have no effect on the physical world. For example, suppose the soul were a perfect analogue to your physical brain, but having no effect whatsoever on the physical world. While the brain can't do anything after death, a soul could, for example, go to paradise. Could we test for that? Well, obviously not. All of our tests must necessarily be physical; physical tests can't detect purely spiritual phenomena.
That being said, we normally raise this question in the context of uploading because people are concerned that if they get uploaded, their souls won't go with them. I know of two basic answers to this; one of them is to say "soul, schmoul; it doesn't exist," and the other is something like this: we have no evidence whatsoever telling us how/when the soul enters or leaves the body over the course of a person's lifetime. Why do we presume that our soul is with us all the time to begin with? It may leave the body whenever we're physicall unconscious, or may only come to us a few times in our lives. All of the atoms in our bodies are replaced dozens of times over the course of a normal lifetime. With that being said, do we have any idea whether our soul stays with us after *any* major physical changes in our bodies? If not, why get so suspicious about uploading?
> 2> We've had transplants of all kinds of organs - but we've never
>had a brain transplant. If I were to detach my brain physically
> from myself, and have it attached to something else that it can
>communicate with (either another body, a machine that reacts
> to it like a body, etc etc) -- would I have the same
>conciousness/be the same person? (this one may not be obvious).
Head transplants have been performed on monkeys. Presuming that you don't think your face/skull has anything to do with identity, this would be an actual test of whether your identity moves with your brain or not.
This may be a question of definitions, however. Suppose you woke up with memories of having fallen asleep in your old body and waking up in the one you're currently in. Would you consider yourself to be the same person? There's no obvious reason why you would have to believe yourself to be the same person; indeed, people today are skeptical about the continuity of consciousness even WITHOUT undergoing head transplants. So what would it prove? Nothing, really. This may be one of those questions where there is no fact of the matter upon which to agree.