callmejay

First of all, a mind IS spatially divisible. You can, through surgery, remove portions of the brain and change things about your mind.

From a different direction, perhaps it's similar to:

1) Computers are spatially divisible.
2) Microsoft Windows is not spatially divisible.
3) Ergo, Microsoft Windows is not identical with a computer.

mtdew

How do you figure? You're cutting apart your brain, not your thoughts. You're spatially dividing little bits of neurons; you aren't taking a knife to your memories. You can't cut out a single memory. You can't take a chunk out of your brain and say, "Hey! There goes 6th grade!" This isn't Harry Potter. You can't pull a thought out of your head. You can alter your consciousness, yes, but not directly. When you alter your mind, you are actually doing (most likely) chemical things to your chemical riddled brain. Thus the imprecise nature of so many drugs. And trepanning.

Look. Two bodies can't occupy the same space. The mind is not an extended substance. The brain is there. You want to argue for the mind as an extended substance, be my guest. You'll just have to explain what all that fleshy neural stuff is doing in your skull in place of "emotions" or "memories."

I repeat. The mind is nothing more than a property of your brain. No one can see a mind. You can't observe a memory; you can't look at a thought. You experience them.

Think of it like this. You cut an apple in two. Is it essentially the same? Yes. It still tastes like an apple. It's still red (or green, depending on preference). It's not, however, whole. Wholeness is a property of the apple. That has changed. You could take a chunk out of it, and it would be mostly whole. It's the same deal with the mind and brain. Metacognition is pretty crazy, I know, but when you cut away parts of your brain, you're altering its properties, not the substance of the mind (the mind has no substance). You flood your brain with chemicals, and you feel differently. There's nothing you can do to a consciousness directly. It's all reflected by little neural firings in your brain. You just experience these firings. These experiences are what you call your "mind." You change the firings, the experience will change.

Essentially, it breaks down like this. If your consciousness is an extended substance, if it has physical properties like weight and color and gravity, it's dualist. But your consciousness doesn't have these properties. It doesn't weigh a certain amount. If it's not an extended substance, then it must be a property of having a brain.

spacer1

mtdew,

While I agree with your overall argument, I wanted to take issue with these comments, relating to the last point I made on this thread:
I wish to know on what grounds can you make this claim? How can you make a claim regarding the divisibility of the wholeness of your thought, when it requires the wholeness of your thought to make such an assertion? It's like trying to say that the universe looks orange from the outside, while never being able to step outside the universe.

mtdew

No, it isn't.

It's like saying I have never seen, read of, or heard of a thought that has weight outside of literary devices.

I've heard of and have read about electrical impulses firing around the frontal lobe aided by a host of chemicals, but the experience of composing this post in my mind is so remarkably different than listening to my girlfriend prattle on about her day, reading about Back-Propagated Neural Networks, or looking at a Dali painting that this entire process of self-awareness and "thought" and "mind" has created a whole new host of hurdles for Philosophy including, "How can I be certain I understand what the other person is trying to communicate to me?" and, "What came first; the girlfriend or the prattling?"

Consider. If you cut off your hand, you lose the function of that hand. You can't make it run around like Thing. It's no longer a "part" of your body; it's just a dead hunk of flesh. The flesh and bones of your body are spatially divisible (ask OSHA; they deal with this all the time), but the concept of "my body" isn't. You can't have a piece of your body under your control, detached from your physical body. It's the same thing with the mind. You can take a chunk out of my brain, but the little bit of brain there is no longer my mind. The special case of subjectivity is gone.

If you remove a hunk of neurons that contain bits of my memory, the sum of my mind is reduced, not divided. In other words, you say I can't assert the mind cannot be divided because of the subjective nature of the question, and I assert the subjective is what makes the mind.

John Page

I had half a mind to respond to the OP.

Jarlaxle

Can a person live with only one hemisphere? If so, which one? If either, are we all two people in one?

Jarlaxle

Split Brain = Split Mind?

The last comment on this page reads:
"The finding that within a split-brain individual, one hemisphere is not aware of the activities of the other implies that whatever the mind may be, it is closely tied to the brain. Splitting the brain splits the mind."

Luiseach

lol

I've thought about this some more, and I want to clarify: the 'mind' as a concept is not spatially divisible, but the physical structure which produces the concept is definitely spatially divisible. The mind is the brain's sense of itself.

John Page

I disagree, examples as follows:
1. There are two (physical) elephants. They are spatially divisible.
2. There are two minds perceiving an elephant. Both minds contain the concept elephant. The concept elephant is spatially divisible.

The two elephants are in physcial form and the two minds are in physcial form. That a shared concept of an "elephant" can simultaneously exist (supervenient on both mind/brains). Accordingly, I can see why elephants are spatially divisible but concepts are not.
I agree with this and suggest it follows that (in a system where) where there is at least one mind per brain, concepts must be divisible in order for us to share their meaning.

Cheers, John

RichardMorey

At the risk of paraphrasing others:

Descartes is right in the sense that the mind and the body are not identical. The mind is instead an emergent property of the organization of parts of that body.

Is this a refutation of materialism, as Descartes would hope? Hardly. Let us imagine a simple automatic mechanical calculating machine. This machine takes input, does a calculation, and gives an output. This 'calculation' (not the output, but the actual act of calculating as it is happening) is not spatially divisible, yet the machine is clearly spatially divisible. The 'act of calculation' is not material, but is the result of only physical processes. We speak of it using nouns and it can fool us into applying ideas that only apply to physical things (as it did Descartes) but needn't.

Richard Morey