WHAT IS THE SOURCE OF CONSCIOUSNESS?

IS THE PHYSICAL THE CAUSE OF THE CONSCIOUS?

Are conscious states in some way made out of the brain?

Are conscious states manufactured, generated, produced by the brain?

Does it make any sense to believe that this squidgy bundle of chemicals fizzing with electricity called the brain is responsible for the special and indescribable taste of olives, the sound of an oboe, the feel of silk, the smell of woodsmoke, the intensity of passion, the terrors of dread, the experience of agony and euphoria?

The idea that the physical (in effect, the brain) is the cause of the conscious (pain, taste, hearing etc.) is a particularly difficult problem because the physical and the conscious have a range of very different and, more importantly, exclusive properties.

More needs to be said about what is meant by this distinction between the physical and the conscious:

The physical is:
SPATIAL, EXTENDED, OPEN TO PUBLIC ACCESS, KNOWN INDIRECTLY AND NON-INTENTIONAL
The conscious is:
NON-SPATIAL, NOT EXTENDED, PRIVATE, DIRECTLY KNOWN AND INTENTIONAL

(Click HERE for a more detailed discussion of the differences between the conscious states and the physical.)

The claim, then, that events in the brain are the cause of conscious states can be broken down into several distinct and contentious sub-claims:

1. that the spatial physical is the cause of the non-spatial conscious

2. that the extended physical is the cause of the non-extended conscious

3. that the publicly observable physical is the cause of the conscious to which only the subject has privileged access

4. that the physical, which is known indirectly, is the cause of the conscious, which is known directly

5. that the physical, which lacks the property of intentionality, is the cause of the conscious, which possesses the property of intentionality.

There may be a complete correlation between the two in the sense that certain conscious states occur only when certain brain events have occurred immediately prior to them. But even if we allow complete correlation between the two (which I do not intend to dispute), we still have an apparently insurmountable impasse to overcome as Kim eloquently shows in connection with a correlation between C-fibres and pain:

'C-fiber stimulation correlates with pain … But why? Can we understand why we experience pain when our C-fibers are firing, and not when our A-fibers are firing? Can we explain why pains, not itches or tickles, correlate with C-fiber firings? Exactly what is it about C-fibers and their excitation that explains the occurrence of a painful, hurting sensation? Why is any sensory quality experienced at all when C-fibers fire?'
(Philosophy of Mind by Jaegwon Kim)

And Chalmers even more succinctly:
‘How could it [consciousness] arise from lumpy gray matter?’
(The Conscious Mind by David Chalmers

Why do we have any experiences at all when our brains are stimulated?

Is there a causal theory that can give an explanation of the link from the physical to the conscious?

I will look at this problem in four sections:

1. a nomological theory of causation
2. a nomological theory of causation that includes spatial contiguity
3. an energy transference theory
4. Searle’s theory of biological naturalism

1. Nomological theory
The idea here is that we normally think of one thing causing an effect when there is a general rule that is being followed. For example, we think that when we press a light switch the light comes on on the grounds that there is a general rule that says that whenever the electrical circuit is completed light bulbs in the circuit heat up and shine. Or we believe that when we hit a drum with a stick there will be a sound on the grounds that whenever vibrating surfaces are struck sound waves are emitted. The problem now is whether we can say the same thing about the physical causing the conscious. It might be that there is a general rule that says that when the cells in the brain fire in a certain way then there is a feeling of touch or whatever. But this situation would equally well fit an occasional relationship as a causal one. (For more on one-way occasionalism click HERE here.) So there might be a regular relationship - this brain state is always followed by this conscious state - but that would not be enough reason to say that the brain state was the cause of the conscious state.

2. Nomological theory of causation that includes spatial contiguity
Because nomological theory on its own does not seem to provide the answer, suppose we add to it the idea of spatial contiguity. What does this mean? It means that to say that x is the cause of y we first of all show that x is regularly followed by y. We then add the new condition that x and y must have some actual physical contact between them. For example, green traffic lights regularly show after the amber traffic light but no one thinks that the amber light is the cause of the green light. They are both caused by the electical system in the lights. There is no direct physical contact between the amber lignt and the green light. But when we start to look for contact between a physical thing like a brain and a non-physical feeling we find that we encounter the difficulty that the feeling is not spatial. How can something that is not spatial be caused by something that is spatial? There is no obvious answer to this question.

3 Energy transference theory
Another assumption we make about causation is that it involves a transfer of energy from cause to effect. For example, if I cause a door to open by pushing on it, energy is being transferred from my body to the door. However, it is difficult to apply this explanation to the idea of consciousness being caused by the body. Take an example of smelling a rose. Particles from the rose enter the nose, information is sent to the brain and energy is transferred from one place to another. When the brain receives this data, there is a conscious experience of smelling the rose. Is some of the energy that enters the body spent in producing the conscious experience? This seems unlikely because, if there were, such a loss would break the law of the conservation of mass and energy. Some energy would have vanished into a non-physical realm. When you think that there are billions of conscious human beings and many billions more conscious animals in the world, there must be a great deal of energy going missing all the time. Surely someone would have noticed this by now?

4. Searle’s theory of biological naturalism
Searle uses comparisons to make his point about consciousness. He says that, for example, a table is a solid thing. Solidity is one of its properties. But if you now think of the atoms and molecules of which the table is made you realise that they are not solid. Atoms are nearly all empty space. So being solid is something the table has on the big scale but does not have at the very micro scale. Consciousness, says Searle, is like this. People say that you cannot find consciousness if you look inside someone's brain. That's true. But then you cannot find solidity if you look inside a table at the atoms of which it is made. Consciousness he considers to be a feature of the complex structure of the brain that is not found in the micro details of the brain.
This all sounds very plausible until you consider that the comparison between the solid quality of the table and consciousness is not really convincing. It breaks down when you notice that the table is a public object at both levels, large and small whereas the brain is a public object and consciousness is in the private domain.

CONCLUSION: It does not seem that any of these approaches to the idea of cause and effect can give an explanation that fits the idea that the physical is the cause of the conscious.

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