Why what you choose doesn't matter: Part 1

Brain: Organ in your head

So what's your "mind"?

Some research indicates that they're the same thing.

There are poor folks out there with intractable epilepsy. A radical therapy is brain surgery in which the corpus callosum - the part of the brain that connects the two hemispheres of the brain - is severed, letting the two halves of the brain operate independently.

These split brain people are pretty interesting. Repeated experiments show that the left half literally doesn't know what the right half is doing and vice versa. "Raise both hands" gets only one arm up, since only the side of the brain that understands language, and the arm that listens to that side, can respond. If you interview the same patient, but different sides of the brain, you get different answers to the same questions.

The dudes who did this work got a Nobel prize for figuring this stuff out. The split brain patients are how we know the right and left brain handle different tasks.

So how does this cast doubt on souls and show that minds and brains are the same thing?

If there were some thing like a soul or mind that was not identical to and in fact separate from the brain, then splitting the brain shouldn't split the mind. The soul or disembodied mind should be able to co-ordinate both sides of the brain. When the mind hears a question, it should give the same answer, no matter which side of the brain the question came through. If the mind wants to be a fireman when he grows up, one shouldn't hear "race car driver" from the right side and "hacker" from the left. But we do, in fact, observe these things.

So when patients with split brains exhibit split minds, we have to conclude that minds and brains are the same thing.

One could argue that we are all, actually, of two minds, and not just one. But while I can't speak for the rest of you, there's only one voice in my head.

And if that's not enough evidence: Antidepressants. How can a chemical lift your spirits if your "spirit" is not actually a thing with which chemicals can react? Unless pharma companies have taught pills to hold seances in your blood stream, drugs can't interact with the spirit world. And if pills can change your feelings, your mind has to be a physical entity.

And the facts that our minds are brains and that our brains are physical objects have some pretty interesting implications. As we'll see in Part II...