Tuesday, April 3, 2018

Physical Connections Do Nothing to Explain Cognition

Let us imagine a thought experiment. Imagine we have a large Olympic-sized swimming pool. Let's suppose we fill the swimming with a gel-like substance about the consistency of jelly that you might spread on your toast. Now let's also imagine that we pour a hundred billion little spheres into this swimming pool, and mix the contents of the swimming pool so that the spheres evenly spread out in the pool, with just as many spheres in any cubic meter of the pool.

Is there any reason at all why we should suspect that anything like a sense of self or a thought or consciousness would come out of this gel-filled swimming pool with all these spheres? Not at all, not unless a human were to jump into the pool.

Now, let's imagine something more complicated. Let's imagine that each of these tiny spheres that were poured into the swimming pool has a special power: the power to physically connect to thousands of other spheres. Let's suppose we activate this power in the spheres, causing thousands of tiny little wires to protrude out of each of these spheres; and let us suppose each of these thousands of wires ends up connecting with some other sphere other than the sphere from which the wire came. Let's imagine that after a week or two there is a situation in which each of the tiny spheres is directly wire-connected to each of thousands of other tiny spheres.

Is there any reason at all why we should suspect that anything like a sense of self or a thought or consciousness would come out of this gel-filled swimming pool with all these spheres, which were connected in such a way? Not at all, not unless a human were to jump into the pool. And if we were to ramp up this technology to another level, so that each of the hundred billion spheres became wire-connected to a million or a billion other spheres in the pool, this would still not give us the slightest reason for thinking that any such thing as a thought or self-hood or understanding would be coming out of this swimming pool, unless a human was in the pool.

So why, then, is it that we suppose that it is the connection of cells in the brain that is somehow able to give rise to our consciousness, our thinking, and our understanding? The swimming pool I have described here is similar to the human brain. The jelly-like gel has the same consistency as the human brain. The little spheres are like the neurons of the brain. The wire connections are like the connections that link neurons in the brain.

There is no reason at all to suspect that physical connection should act as some magic wand causing consciousness or understanding or self-hood to appear. Consider a crystal lattice. This is a regular structure in which all the atoms are connected by bonds. In a crystal lattice you could follow the bonds to trace a path from any one atom in the crystal to any other atom in the crystal. But no one that I know of has ever suspected that a crystal might be conscious because of such an arrangement of atoms. Mere physical connection does nothing to explain consciousness or understanding or self-hood.

Consider the global telephone system. There are now almost as many cell phone subscribers as there are people. This means the global telephone system is a connected network of billions of nodes. Most of these nodes are smart phones or cell phones with capabilities greater than neurons. But while the idea of an intelligence arising from a phone network was once fancifully suggested by the science fiction writer Arthur C. Clarke in the story Dial F for Frankenstein, I know of no one who has seriously suggested that the global phone network may be conscious. Nor do I know of anyone who has seriously argued that the global computer network known as the Internet has achieved a kind of self-hood or consciousness or an understanding of itself.

Inside a heart or a liver of a large animal like a whale or an elephant, there are innumerable cells connected by tiny capillaries. Since there are 10 billion capillaries in the human body, we may presume there are billions of connecting capillaries in the organ systems of an elephant or a whale. But nobody ever thinks that such a high degree of connection causes an elephant or a whale to have some mind that is created from underneath its neck.

The human brain has an architecture in which connection is the most prominent feature. But there is no reason to think that such a high degree of connection should in any way be something that can explain the main characteristics of the human mind.  A 2010 book by two neuroscientists states in its preface, "The neuroscience literature contains many speculations about how the brain computes, but none is well established." 

Let me tell a little science fiction story. Once there was a planet on which most of a continent was covered by a densely packed jungle. The trees of this jungle had long thin branches and vines that could connect with many other trees. A particular tree might have branches and vines that stretched out for hundreds of meters, connecting with hundreds of other trees. But there was something very remarkable about this jungle. When most arrangements of these trees and branches and vines existed, the huge jungle was just an ordinary jungle, no more conscious than a stone. But when there got to be a sufficiently great density of these trees and branches and vines, the jungle became a self-conscious mind, and was capable of judgment, analysis, insight, imagination and self-conscious experience.

The story isn't very believable, is it? Why should a jungle become self-conscious merely because there was some particular arrangement of trees and branches and vines? But such a story is just like the story that our neurologists ask us to believe. We are told that we have consciousness merely because of a particular arrangement of densely packed nerve cells and dendrites connecting different cells – an arrangement quite like that of the jungle just described, except that instead of trees it is nerve cells, and instead of branches it is dendrites, and instead of vines it is axons.

Nor will it work to try to appeal to computers to justify the "connections lead to cognition" idea. It is true that if you open up a back of a supercomputer, you will see many wires connecting things. But there is no computer in the world that has any type of real understanding or cognition.  Computers do processing and information crunching, but there is no computer with the slightest understanding of any abstract concept.  Understanding only occurs in minds, and computers don't have minds. 

Some might try to use the “you shouldn't expect mind from neurons” situation to argumentative advantage by saying, “Yes, it's unexpected – it's an example of emergence.” Here is how one William Hasker tries to do this on page 212 of a book called, “The Soul Hypothesis”:

The general idea of emergence is that when one brings together elements of a certain sort, and arranges them in a proper way, something genuinely new appears, something that did not exist in the elements prior to their combination. The new thing isn't just a rearrangement of what was there before, but neither is it something dropped into the situation from outside. It “emerges,” comes into being, through the operation of the constituent elements, yet the new thing is something different, and often surprising; we wouldn't have expected it before it appeared. Take a mathematical equation of a certain sort, plot it onto a set of coordinates, and a fractal pattern appears – complex, unexpected, and sometimes stunningly beautiful. Dissolve some chemicals in water, let the solution stand for a while under the right conditions, and regular, highly organized crystals are formed. When the right numbers and kinds of chemical molecules are arranged in a particular complex structure, we have something new – a living cell. And given a sufficient number of the right kinds of cells, properly organized, there is the wonder of awareness, involving sensation, emotion, and rational thought. In each case, what “emerges” is something qualitatively new – a fractal pattern, a crystalline structure, life consciousness.

Hasker's statement has a certain superficial appeal, but it does not stand up to close scrutiny. Let's look carefully at some of the examples he has provided.

A fractal pattern is a case in which a particular algorithm using what is called recursion is combined with some graphics software. What do we expect to get from this? We expect graphics output, and that's just what we get. With such output there is the property that you can zoom in, and keep continuing to get a certain type of detail. But given the recursive nature of the algorithm, that's just what should be expected. There's no wondrous “emergence” in this case; we expected some graphic output, and we got it. And even if the result was unexpected, you would hardly be justified in using such a feeble example (mere graphics output) as something that might justify conclusions about the almost infinitely more substantial effects of the human mind (such as consciousness, abstract thinking and memory).

As for Hasker's example involving a crystallization of water, there's no real emergence going on there. Such a crystallization is quite predictable, given the laws of chemistry and physics. Nothing unexpected has happened. The crystal pattern is nothing new that has emerged. We simply use the term “crystal pattern” to refer to a particular type of arrangement of molecules. Similarly, there is no non-trivial “emergence” going on when I arrange 12 pennies into a circle; in no non-trivial sense does circularity emerge if I do that.

Hasker then says, “When the right numbers and kinds of chemical molecules are arranged in a particular complex structure, we have something new – a living cell.” This is an invalid example, because no one has ever observed any such thing occurring. Scientists absolutely are not able to make living cells come into existence by combining mere chemical molecules. Many scientists assume that the first living cell arose from a mere chance combination of chemicals, but that assumption is unproven and very dubious, because the chance of such a combination producing life seems fantastically unlikely.

In short, Hasker has not given us any examples that justify the “mind from mere cells” thinking of his claim that “given a sufficient number of the right kinds of cells, properly organized, there is the wonder of awareness, involving sensation, emotion, and rational thought.” None of his previous examples justify thinking that the wonder of rational thought and awareness is something that we should expect to jump out from “a sufficient number of the right kinds of cells, properly organized.”

Another example sometimes given to justify philosophical notions of emergence is the fact that when hydrogen and oxygen combine to become water, a novel property of “wetness” emerges. But in one sense such a thing is not unexpected. The general rule in chemistry is: combine two elements to make a compound, and you will get something new with its own chemical properties different from those of any of its constituents. That's exactly what happens when hydrogen and oxygen combine to make water. So in one major sense it's not at all unexpected that we would see some new property or characteristic.

All such examples of “emergence” fail to justify “mind from brain matter” assumptions, for the general reason that they are all cases of one thing physical producing something else physical. Even in the fractal example, we are dealing with something physical, as the fractal pattern is produced on some computer hardware that uses software. Even if you could establish that novel physical characteristics arise unpredictably from physical things, this would not justify the very different conclusion that mental capabilities arise from mere cells.

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