In that book, Sam Harris talks about consciousness and what makes us who we are. He describes (paraphrasing) how we feel as if we’re something riding around in our heads and looking through our eyes. He explains what consciousness is”
“an experiential internal qualitative dimension to any physical system.” Put more simply, consciousness is what it’s like and how it feels to be you.
He then goes on to talk about the ego or the sense of ‘I’ that we experience as human beings:
“The sense of being an ego, an I, a thinker of thoughts in addition to the thoughts. An experiencer in addition to the experience. The sense that we all have of riding around inside our heads as a kind of a passenger in the vehicle of the body…. Now that sense of being a subject, a locus of consciousness inside the head is an illusion. It makes no neuro-anatomical sense. There’s no place in the brain for your ego to be hiding.”
Later he talks about a medical procedure called calloscotomy, which inhibits the right hemisphere from communicating with the left. They have done this procedure to people who suffer from severe epileptic seizures. They’ve also performed this procedure on various animals, including cats and monkeys.
So here’s the really interesting part. In my opinion anyways – when they do this procedure, it’s as if they create two consciousnesses in one skull. It’s creepy but it’s almost as if two people are sharing the same body.
In one test, they showed a subject who had undergone this procedure a set of four different colored blocks. Then they showed him a picture of the blocks in some arrangement in front of him and asked him to duplicate it with his blocks. The subjects right hand (the left hemisphere controls the right side as well as visual-motor capacity) was easily able to complete the task, but the left hand (controlled by the right hemisphere) could not.
However, it gets even stranger:
But more surprising was this: As the right hand kept trying to get the blocks to match up to the picture, the more capable left hand would creep over to the right hand to intervene, as if it realized how incompetent the right hand was. This occurred so frequently that Gazzaniga eventually asked Jenkins to sit on his left hand so it wouldn’t butt in.
When Gazzaniga let Jenkins use both hands to solve the problem in another trial, he again saw the two brain hemispheres at odds with one another. “One hand tried to undo the accomplishments of the other,” he wrote. “The left hand would make a move to get things correct and the right hand would undo the gain. It looked like two separate mental systems were struggling for their view of the world.”
The take away from this experiment and many more that they’ve done since is this:
“The demonstration that you could in effect split consciousness by splitting anatomy—by just making a tiny change in anatomy … It was one of the most remarkable results in neuroscience, with huge implications,” said Patricia Churchland, a philosopher at the University of California, San Diego, whose work focuses on the relationship between philosophy and neuroscience. “If you thought that consciousness and mental states were independent of the brain, then this should have been a real wake-up call.”
Helping to illuminate the relationship between the mind and the brain, according to the cognitive psychologist Steven Pinker, is one of split-brain research’s most important contributions to modern psychology and neuroscience. “The fact that each hemisphere supports its own coherent, conscious stream of thought highlights that consciousness is a product of brain activity,” he told me. “The notion that there is a single entity called consciousness, without components or parts, is false.”
We have often described our ‘self’ as something separate from our bodies. Most of our religions describe some sort of soul that leaves or changes as we die, but this experiment shows that by simply cutting off communication between our two hemispheres, we can create two consciousnesses that are independent of one another.
While you’re reading this, you could have two different opinions of this piece, depending on which hemisphere you asked.
How creepy but fascinating is that? And are there more ‘I’s’ lurking around in our skulls that we haven’t discovered yet?
No matter how you look at it, I think this shows that the soul doesn’t exist if you think your consciousness or the thing that you describe as ‘I’ or ‘you’ is essentially what your soul is.
What do you think?