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Consciousness

This article looks at consciousness in light of the inferred materialism. Even though materialism is a fairly simple and straightforward idea, consciousness is more mysterious.

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What is Consciousness?

What is a force? If we define it as ‘a force’ that is totally unhelpful. We have to define it in terms of something else with which people are familiar. Defining it as ‘a push or a pull’ is much more helpful.

What is consciousness?

Woman

To be helpful, consciousness has to be defined in terms of something else. The trouble is that there is nothing else like consciousness, and that makes it hard.

Consciousness is often described as awareness, perception, thoughts, experience, knowing, feeling, what it’s like to be something, and the like, but these are really just other words/expressions for consciousness and they cannot be defined any more easily than consciousness itself.

In a sense, though, not being able to define consciousness shouldn’t really be a problem because we all (presumably) know what it is - we experience it. It's not like we're trying to explain what it is to someone who hasn't experienced it.

[Note that we are not talking here about being conscious of something in our environment or of something that we did, but more of the general knowing that one exists and is aware. Though, of course, without a suitable definition, it's impossible to express that idea precisely.]

How does Consciousness Arise?

Even though consciousness is something we are all familiar with, understanding how it comes about is a different matter. The materialist idea is that it results from the electrical and chemical activity of the brain, yet it seems so completely different from that kind of activity that it is hard to see how this could happen.

Neurons

Dualists see it as being a feature of the soul rather than the brain. But they can’t tell us what the soul is, or explain how it works or how it gives rise to consciousness either. Instead they just assert that the soul as an entity which doesn’t need to be described or explained.

Anyway, as can be seen in other articles on this site (in particular, ‘Existence’ and ‘Free Will and the Soul’), the most likely case is that there is no soul and consciousness is just an emergent property of the activity of the brain.

Consciousness does always seems to involve memories, perhaps along with current sensory input. It seems reasonable to assume that it relies on these and results from them. It is hard to imagine someone with no memory and no sensory input having anything to be conscious of. They wouldn’t even be aware of the lack of memory or sensory input, because, having no memory, they wouldn’t know that such things could exist.

Degrees of Consciousness

A human embryo with the beginnings of a brain would be unlikely to have much of a consciousness. It seems likely that a rudimentary and very limited consciousness develops in the womb (from sounds and maybe feelings), and that a much fuller consciousness develops once the baby is born and experiences a greater variety of sensory input.

If an embryo had the consciousness of an adult, it would get very bored with 9 months floating upside down, doing nothing but giving its mother the occasional kick. Also, if consciousness were an all-or nothing phenomenon, then it would have to have started at an instant in time. It would be hard to see how this would happen in the context of the gradual development of the embryo and its nervous system.

So it would seem that there can be degrees of consciousness ranging on Earth from nothing to that of the most conscious human. In general, humans have a well-developed consciousness. Dogs appear to be conscious too, though maybe less so than humans. Spiders may have a rudimentary consciousness. But bacteria probably don’t. If consciousness results from brain activity, having a brain would probably be a pre-requisite. The same would go for trees and rocks.

It is conceivable that extra-terrestrials millions of years ahead of us in their evolution might have a degree of consciousness that we couldn’t imagine. Or in fact that humans might get to that state if we survive a few more million years.

Consciousness is Unobservable from the Outside

One thing about consciousness is that it cannot be seen by an outsider: only the person experiencing it knows it’s there. I know I’m conscious, but cannot tell if anyone else is. Because they seem to be very much like me – they converse with me the way I converse and seem to know and think similar things to what I know and think, I tend to assume that they are.

But then a computer programmed with artificial intelligence can hold a conversation with me to the extent, that, if I am talking to it online, I cannot tell that it isn't human. So, either that is not a sufficient criterion for consciousness, or I have to assume that the computer is conscious. That sounds unlikely, but then I have no way of knowing. In a sense, our brains are complex computers which manifest a high degree of consciousness. Maybe simple computers have a very basic consciousness.

Split Brains

The corpus callosum is a bundle of around 200 million nerve fibres which connect the two hemispheres of the cerebral cortex.

Corpus callosum

It was discovered in the 1960s that cutting the corpus callosum could cure otherwise intractible cases of serious and debilitating epilepsy. The idea was that the separation of the two halves would stop the chain reactions of nerve firings crossing back and forth between the two hemispheres. Not only did the procedure produce the desired result, but the patients seemed to be fairly normal afterwards.

However, researchers experimenting with split-brain patients found some interesting things.

The left side of the brain receives visual information from the right half of the field of view and vice versa. It also receives sensory information from the right half of the body and controls the movement of the right half of the body. The left half of the brain produces and understands speech; the right half seems to be able to understand to some extent, but cannot generate speech at all.

The researchers flashed images to the right side of the patient’s field of view and asked what it was. The patient answered correctly. But, when an image was flashed to the left half of the field of view, the patient said they didn’t see anything. However, when showed a group of objects, one of which was what had been flashed, the patient could pick out the correct object with their left hand. When asked why they had picked that object, the patient made up some story to justify it.

What seemed to be happening was that the left half of the patient’s brain had a mind that was unaware of what was going on in the right half of the brain. It could get clues by seeing what the left hand was doing, but would only see the actions, not be aware of the thoughts. So it had to make up reasons why the left hand did certain things.

It was possible to hold a conversation with the left-half mind because it could speak, but the right half, while it seemed to have some understanding of what was said to it, could only communicate through body movements.

In most cases, the right brain seemed to be meekly cooperative with what the left brain was trying to do, though not always. On one occasion a patient was buttoning up his shirt with his right hand while his left hand was unbuttoning it again.

The left-half mind said it didn’t really feel any different after the operation and seemed to be just as conscious as before. The right half seemed to have a will of its own and, though it couldn’t speak, it seems that it might well have its own consciousness. This suggests that split brain patients could have two independent minds. The question arises ‘Do normal people have two minds or does the constant sharing of data between the two minds make them effectively one mind?’

One is left to wonder whether the mind is really the well-defined, discrete, unified entity that we tend to think it is.

Finally, if there was a heaven and a hell, it would be conceivable that, in the case of a split-brain patient, the right half could be bound for heaven while the left half is bound for hell. This is another consideration that makes the idea of judgment and an afterlife problematic.

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Image Acknowledgements

Woman: Freerange Stock
Neurons: File:1 sinapse durante o sono - prompt Sergio Valle Duarte.jpg (cropped) - Wikimedia Commons
Brain: Wikimedia Commons