Drakodan Posted:

man-man, I can certainly understand what you mean, but there have been successful brain transplants, as well as putting people to sleep during operations, which involves switching the body off.

Brain transplants? Not that I’ve heard of… quite aside from immune rejection, the problem of connecting the brain stem to a foreign spinal cord in such a way that it actually had sensible control over a new body… that is a little beyond current science insofar as I’m aware of it. Maybe eventually we’ll standardise the brain/spine connection onto USB 5.0 and be able to hot-swap brains and bodies (or plug ourselves into immersive virtual worlds, Matrix style) but not yet…

Drakodan Posted:

And anyway, as you say, the brain itself switches off and dies. But what is it INSIDE the brain that makes us, well, us? Consciousness, for certain. I’d prefer to call it the soul. Like I say, its not something I’m entirely sure of yet, but something I’m certainly willing to consider.

The unique pattern of neuronal connections and chemical influences contained in the brain. At birth there’s a certain level of predetermined templating, to define where the various regions of the brain go (don’t want the optic nerve at the back, that kind of thing) but considering the billions of neurons available, there’s more possible ways of wiring a person up than … well I don’t know the number, but it’s on the order of a metric ****-tonne. Far more than enough for 7 billion unique human minds.

It’s not so much the individual neurons, as the patterns they instantiate – you can lose some of the individual cells and the patterns survive, but lose too many (to oxygen starvation, brain damage, anything that kills cells or disrupts their connections to one another) and the pattern is destroyed. Maybe that kills you, maybe it just impairs some part of your cognitive function, maybe you just lose a couple of memories… there’s constant rewiring in progress, so losing a pattern here or there is only to be expected, but you don’t want the important ones being lost.

Duncecap Posted:

In any case, there is no need for the ‘soul’ to be non-physical.

The part that makes the brain the thinking centre, as previously stated here in this topic, is the arrangement of the neurons and their connections. The brain is hardware; the part that you identify as ‘you’ is the software, and merely an internal state of the brain.

Lose that internal state, lose that arrangement, and what is left? The blank hardware. No personality, no memories.

You do want to be careful with that analogy – take the “bare metal” of a brain with no connections or arrangement and you don’t have a working brain at all. By the time you’ve got it connected up enough to be functioning there could well be some fledgling elements of personality in there. That, and in a normal brain the parts that make you ‘you’ aren’t distinct from the ‘hardware’ – you couldn’t take the same brain and use it to run a different ‘program’. Your personality, your consciousness, all those things that define a person, are present in the very solidly physical state of the brain, not some abstract ‘internal state’ that could be separated from the neurons.

There may seem to be a ghost in the machine, but it’s a ghost made out of machinery.

SoronTheBeast Posted:

In most of Christianity (generally speaking), “the soul” would be the spark of the divine in humans only that gives us life and free will. [..] It’s also the part of you that takes your experiences and “self” up to heaven or down to hell when you die. Like a repository of all your thoughts and memories.

I would say, without this kind of soul, it’s hard to prove free will exists.

Scientifically, “the soul” would be the “spark of life” all living things have. Why can’t you get a dead body to start up again with the right chemicals or something? Because a living thing is so complex that once its harmony is disrupted it can’t be gotten back. That harmony would be the “soul.” Some living things are more complex than others, so there even harder to “get back.” Once the brain is damaged, the unique ordering of chemicals and electronically impulses that makes you “you” is gone. That would be the “soul” scientifically.

I don’t know whether I think this scientific soul is worth calling a soul; I take the word as strongly implying a separate entity from the body, one that’s generally believed to survive the death of the body. The scientific equivalent is more like a convenient shorthand for the particular state of a brain and body (the body affecting the brain via hormones and chemical signals and the like), the combination of which make a unique person. I agree in the broad strokes with what you’re saying – a personality is in the chemicals and impulses, not a magical non-physical spirit, but calling the chemicals and impulses a soul seems to me to carry too many excess connotations.

SoronTheBeast Posted:

Really, I’m talking about two kinds of ‘scientific soul.’ One being a “life force” the other being a “repository of thoughts and experiences.”

But, for both kinds of “scientific souls” we are talking about an unique ordering of chemicals and electrical impulses. One ordering, which I called “harmony” above, keeps you alive. The other I am talking about is the ordering in the brain that gives you (or any animal really) memories and a personalty. For exampled, some dogs are mean and some dogs are nice.

I’d still consider it short of the definition of soul, but we may be working to different definitions; I consider the ‘survives death’ part to be the main characteristic of a soul. I don’t believe such a thing exists, so I don’t think there is a ‘scientific soul’. Granted though, there are physical patterns of chemicals and neurons that keep a body alive and instantiate a personality. If you want to call it a soul then carry on…

[and then I see that in your later post you’ve said much the same as I just did – mixing definitions is a Bad Idea™. As for world views, you may be able to tell I’d count myself a materialist. There are some very interesting ‘high level’ properties to matter, but nothing that isn’t founded on physical stuff. By high level, I mean that thoughts and memories are high level features of brain cells in the same way as “wetness” is a high level feature of water molecules – you can’t satisfactorily describe what “wet” means in terms of water molecules, even though there’s nothing causing the wetness except for those same molecules, just as you can’t really describe a thought in terms of brain cells, even though there’s nothing but brain cells involved in thought.

I sometimes tend towards materialistic functionalism; that thinking can be seen as a function of the brain in the same way as digestion is a function of the stomach, but functionalism as a theory doesn’t really say a great deal. It’s hard to find a part of it to disagree with, but that’s largely because it’s an ‘anything goes’ kind of theory.