Jun 19 2007

A Turing Test for a Cell Phone and Dividing the Brain

Michael Egnor is slowly working his way through all the bogus and discredited arguments for dualism – the notion that the mind is separate from the physical brain. He just won’t stop. I think it’s a good skeptical exercise to go through these arguments and expose their fallacious logic. So as long as Egnor keeps setting them up, I’ll keep knocking them down.

His latest entries are thought experiments (and I use the term lightly). In the first he imagines scientists on an island finding a cell phone and whether or not they could discover if the voices coming from the phone were created by the phone for were merely being received by the phone. Get it – the phone is the human brain. He is recycling the argument that the brain is a receiver for the mind, not the generator of the mind. This is a way to explain all of the evidence that links the brain to the mind by saying that the brain is necessary, just as a phone is necessary to have a phone conversation. But the brain does not create the mind just as a phone does not create the voices that come out of it.

Orac has done a nice job of destroying this bit of nonsense from Egnor.  I will just summarize the main points, which Orac hit nicely, and extend them a bit.

Scientists can conduct experiments to distinguish between a generator and a receiver, whether a phone or a brain. The first and most simple is to see if the phone/brain can generate a voice/mind if it is being cut off from the outside – presumably from any outside signals. This happens all the time for cell phone users, resulting in those annoying dropped calls.

No one has been able to similarly shut off the mind from the brain. The mind continues to exist as long as the brain continues to function, regardless of other factors. Of course, this can easily be turned into an unfalsifiable claim – you can’t isolate the brain from the soul or whatever creates the mind, since it is spiritual and not dependent upon any physical laws. This is the only way to rescue this claim, and it also renders it non-scientific and therefore useless (Intelligent design proponents are really good at that).

The second way to test it was anticipated by Egnor, but he totally blew the thought experiment by missing the point (ID proponents are really good at that too). He writes:

“They show that all kinds of things — chemicals, mechanical impacts, electrical interference — can change or ablate the voices. They find that certain sounds the voices make are consistently associated with patterns of activation in the cell phone circuits. They found that some aspects of the voices — tone, amplitude, etc. — are localized within the cell phone. They conclude that the voices are simply an emergent property of the cell phone circuits!”

Egnor is saying that because physical manipulation can change the physical properties of the voice coming from the cell phone does not mean that the phone is causing the voices. He goes on to argue that the content of the voices – meaning, emotion, etc. cannot be altered by futzing with the phone, because the phone does not cause those voices.

But Egnor never closes the deal. He does not complete this analogy with the brain. His analogy is dependent on the unstated claim that by manipulating the brain chemically, physically, electrically we can alter physical aspects of its function, but not the meaningful content of the mind. The claim is unstated perhaps because it is completely untrue – we can change emotion, memories, personality, and behavior – everything that qualifies as the mind, by manipulating the physical structure of the brain. Right there the analogy breaks down, and in fact Egnor’s thought experiment, if done properly, proves my point and disproves his.

Rather than exploring this aspect of the analogy, Egnor side steps it with a tautology. He takes as a premise that “meaning” is not physical, and therefore cannot come from something that is physical. He tries to rescue his analogy by assuming as a premise the conclusion he is trying to prove. But “meaning” is just an abstraction we assign to patterns of thoughts, moods, and behaviors, which in turn are demonstrably created by the brain.

The second thought experiment
has to do with dividing the brain. Egnor writes:

“Imagine that we can do complete split brain operations. We can separate the hemispheres of the brain completely, and not just partially as we can do now with corpus callosotomies. We can then further subdivide the tissue, keeping the brain parts biologically alive, in quarters, eighths, etc. Ignoring for the time being what would happen to the person’s consciousness (which brain part would mediate the first person experience of the original person, if any?), what would happen to the original person’s altruism? Would each one-eighth brain have one-eighth the altruism? Would each lobe contribute one-eighth of the previous brain’s annual contribution to the United Way? Would the altruism stay in one of the lobes- the left occipital lobe, and leave the other lobes heartless? What if we kept dividing? Is there an altruism neuron? The question seems nonsensical. Altruism, as an idea, doesn’t have ‘parts’. Unlike matter, ideas can’t be divided or localized.”

Wow. Coming from a lay person this would be a reasonable if naïve question. Coming from a neurosurgeon – well, wow. Egnor clearly has not thought much about brain function.

What makes a person – you – is the function of your entire brain working together. If you take away a piece of the brain what is left is part, but not all, of you. Neurologists see this all the time. If a person has a stroke in their non-dominant parietal lobe they will have a syndrome of neglect – they cannot see or even think about the opposite (usually left) side of the world. Are they the same person they were? Well, yes, minus the ability to see or think about everything on the left of them. Amazingly, they do not notice the deficit, they cannot perceive that the problem is with them. The concept is just missing – it’s gone with that part of the brain damaged by the stroke.

There are many similar syndromes of loss of a specific neurological function following damage to a piece of the brain. This includes loss of certain personality traits. If the frontal lobes are damaged that can result in the loss of the ability to censor oneself. This can cause a previously nice and friendly person to become a loudmouth jerk.

Let me give yet another example, this one everyone can relate to. When we are dreaming our brains are clearly active, and we are ourselves. But we are not quite ourselves. The dreaming self is a different version of ourselves. For example, very strange things often happen in our dreams and we accept them as true – things our waking selves would never accept so easily. Clearly our dreaming thought processes are different then our waking thought processes. This is because our entire cortex is not active during dreaming, in fact the reality testing part of our brains is not as active.

So in Egnor’s thought experiment as the brain is divided we would be creating partial selves, a subset of human consciousness with pieces missing. One of those pieces could indeed be altruism.

The other component of the though experiment, however, deals with how small a piece of brain can you have and still have consciousness. This is an interesting question – it is similar to asking about animals that have simpler and simpler nervous systems and at one point are animals truly conscious. There are two schools of thought here. The first is that both situations are a continuum. So a bacteria and a single neuron have a tiny amount of consciousness. The other approach is to say there consciousness requires a certain minimum threshold of complexity and function before it emerges. And therefore, below that fuzzy minimum there is no consciousness, and above it you have the beginnings of true consciousness.

I don’t know that we can solve the problem and definitely answer the question – continuum vs threshold. But that is irrelevant to Egnor’s point, which is not valid. He is saying that this all means that consciousness does not come from matter. That is simply absurd. It is like asking how much air is necessary to create weather. Does one air molecule have weather – how about two? Is there a threshold or is it a continuum? Egnor’s logic would also imply that these questions mean weather is not created by the matter in the atmosphere and the earth’s surface – it must be made by weather fairies.

To reiterate – complex behavior and phenomena can emerge from complex systems, and there will always be the problem of defining what happens to such emergent properties at different levels of complexity. At what point down the simplicity scale does the emergent property disappear – or does it? This does not mean that the emergent property is not created by the complex physical system in the first place.

The intellectual sloppiness of Egnor is astounding – but what we have come to expect from the Intelligent Design community. Which leads me to a final point – scientific skepticism is all about method, and the core virtues of that method are intellectual honesty and carefulness. Scientists don’t really care what the answer is – what the origins of life are, for example – we just care about finding the truth whatever it is and that is tied to methodology. So ultimately we care about method. ID proponents care about the answer – they need the answer to be creation and not evolution, and they distort and destroy the method to achieve that end. Egnor’s sloppy thought experiments are just another reminder of that.

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