WHY RATIONAL PEOPLE DISAGREE

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In this essay I shall try to share some insights - and sources - that have inspired me in recent years. 

I will explore the nature of human knowledge, and our knowledge of human nature, as they affect our capability to agree on a common understanding and program of action. 

We consider Science (in the abstract) to be a higher authority than our own personal experience, and at first glance we think of the scientific method as the application of Reason to practical and theoretical problems. Our experience of learning, and of using, science is one of applying well-established principles in a chain of cause-and-effect reasoning to solve problems about what to expect in the working of natural systems, and even to provide quantitative guidance for our own effort when we design systems to do what we want. 

With further thought we realize that the authority of the scientific method rests not on the certainty of our reasoning, but on the collective experience of a worldwide community of sophisticated and skeptical users who can test the validity of ideas for themselves. They appreciate the historic strokes of genius in perceiving facts and principles that we take for granted today, but they realize that plausible explanations can be invented easily, and that an idea that cannot be tested quantitatively is not of much use. They repeat the experiments, and work out the consequences, and explore the limits of applicability, of any contribution to this body of knowledge. The ideas, from diverse sources, that survive this critical test become an inter-connected system of rational explanations only in the course of retelling and teaching.  In this sense Science is an example of cultural evolution. 
  

In this spirit the rationality, and irrationality, of human behavior and subjective experience becomes the subject of scientific curiosity, of philosophical pronouncements, and of technological manipulation. We have accumulated quite a variety of explanatory knowledge, from experiments with other life forms and with human volunteers, and from medical observations of patients with neurological damage from accident or disease, in comparison with normal subjects. For example the electrochemical chain reaction responsible for propagation of nerve impulses was worked out in the 1950's at the Wood's Hole Biological Institute, Cape Cod, using nerve fibers of the squid called giant axons, which are about 1000 times larger than most neurons and could be impaled with electrodes to stimulate and measure their vital processes. The visual system was explored in the 1960's with experiments on rats and cats. 

Let me illustrate with a demonstration of psychochemistry in action. Please stare at this wheel [see note] while I am talking and we will see an example of what I am talking about. The retina of the eye has evolved as a part of the central nervous system and it contains layers of associative neurons that function like brain cells. The optic nerve contains fibers that transmit signals to the cortex of the brain, but not in the point-to-point pattern that we would expect to project an image. Now look at the other disc and note that the printing has gotten dizzy! We see it turning, but we know it is not. If you look back at the turning wheel for about half a minute, and then look at any patterned surface - the carpet or the wood grain on the wall, you can see the effect again. The phenomenon, called nystagmus, seems localized in only a part of the visual field, and it demonstrates that the discrimination of movement is localized in the retina of the eye, not the brain. 

 
Experiments in the 1960's demonstrated that single fibers of the optic nerve were stimulated by abstract properties of the image projected in the eye: motion, contrast, directionality of pattern features. The associative neurons collect inputs from a multitude of the rod and cone cells that are stimulated by light and pass them on selectively to the optic nerve. They are both stimulated and inhibited by signals from up to about 1000 synapses and each one detects a particular kind of spatial and temporal pattern in the surrounding visual field. 

This demonstration shows that our exquisite sensitivity of discrimination for moment-to-moment changes in the visual field is dynamically balanced to register a stationary background in order to perceive very slight motions. The synapses, where nerve cells pass signals from one to another, discriminate between stimulus and inhibition with a balance that depends on a chemical environment that is constantly adjusted. This adjustment changes when we fool it with a constantly-moving object, by means of a chemical process that has a time-constant of about half a minute, and recovers in a similar time when we go back to a more normal visual field. 

This experiment illustrates that our perception of the world around us is a dynamic process of creating an internal representation of our surroundings, out of abstract attributes that are communicated from our sense organs. We learn how to interpret these signals, to "make sense" of them, and we interact by taking another look as needed to fill in the blanks. We interpret the visual and other sensory patterns according to our past experience and fill in more blanks from our accumulated knowledge. We know about the back sides of things even when we can't see them and we know what to expect when objects move. Even more, we know what to expect from our own efforts to move since our bodily kinesthetics keep us informed in that regard. 
 
 These are all processes that we have in common with other life forms and that do not depend on the sequential thought patterns that we call reasoning. Even an insect conceptualizes its surroundings, and its muscular efforts, in this sense to get where it wants to go. Our cognitive awareness of our surroundings is the automatic result of many mental and physiological processes that "take care of themselves" and proceed without our giving them any attention except when they demand attention because we must respond consciously. These are parallel processes in the sense that they do not wait for each other but proceed independently. 
 
 
The Scientific Method, of inventing a theory, working out its consequences, and comparing with further observation to refine the theory was selected for its survival value - that is, it evolved biologically - in cognitive processes long before we had the capability to know that we know. It just happened and we lived our lives reacting to the resulting awareness of our surroundings, including the capability to imagine a variety of possible outcomes. We share with other life forms the necessity to balance between commitment to action versus reconsideration to explore other possibilities. 

The capability for symbolic thought has taken credit for our "higher faculties" but I submit that that is nothing new. In the non-verbal context of spatial relations we can imagine various possibilities, and compare and select the best alternative. This is also symbolic thought but we do it so easily that we are not aware of its creative attributes, although we marvel at the wisdom of wild animals in their natural habitats.  

These thoughts are from a book by Howard Margolis titled Patterns, Thinking, and Cognition, where he develops an argument of evolutionary plausibility for this aspect of associative systems. 

 
Science is a bad word today because it is cited as a Higher Authority by those who would have us buy a product, or a candidate, or a public policy, on faith - just the opposite of the open mind and critical attitude that really is science. 

"Evolution is just survival of the fittest" has become an elitist, antidemocratic ideology which is used by the private-profit-at-any-price ideologues in our modern commercialized culture to excuse abuses of economic power just as the observations of Malthus on population dynamics were used to justify genocide in Ireland and elsewhere in the British Empire, and in this century by the NAZI Master Race.

Evolution as a catchword for passive acceptance of whatever exists does not explain anything, any more than God does, and we must refine our ideas to provide a better framework for comprehending the wealth of phenomena in living systems. 

In a previous book, Selfishness, Altruism, and Rationality, Margolis develops a theory of self-interest that he postulates as a genetic heritage of natural selection of instincts for group survival.  He uses the idea of "fair share" as the basis for individual choice in distributing one's resources between personal and public purposes, and the justification for this evolutionary explanation is the observed behavior of real populations in supporting public purposes as well as private, cooperation as well as competition. 

We also observe co-evolution of species in an ecosystem where each species has a marginal existence, limited by available resources, but the whole environment evolves to make the best use of natural inputs. Cooperation and competition are both useful ideas in understanding a real natural system. 

Another observed result of natural selection pressure is the survival value of genetic diversity in a population, so that adaptation to changed circumstances does not need to wait for random mutations that fit the need and are also viable. Witness mankind's success in selecting domestic crops and animals for many specialized uses. 

Our dog Barney, who is half Labrador Retriever, is an example of the psychochemistry of motivation. He has recently learned, to his great joy, that when he barks with a certain voice we will look at his water bowl and fill it if necessary. While we fill the bowl he goes out through his dog door to the enclosed yard, and comes back. He doesn't need an explanation of that behavior, but we do. He just wants to do it, and we are not privy to his stream-of-consciousness wishes that move him on his way. 

But we do understand the unnatural selection pressure of human breeders that made him what he is. People play God all the time, and bird-shooters want dogs to do the messy part of retrieving dead birds from the water. We can theorize that the association of people and water somehow triggers his instinct to do his job, and his gesture of going out seems to him to serve that purpose. This reasoning on our part is an example of evolutionary plausibility as an explanation of observed phenomena, and we can never be certain that we have found "the reason". If the idea helps us to organize our attention and perceive more examples that fit it we will like it better; if it only helps us to recognize conflicting examples that is also a useful result and we will seek another explanation. 

Humankind has evolved a capability to communicate and hence to work together that has such a survival value that we now find ourselves in charge of the world!  The selective pressure for linguistic capability has been so effective, both in competition with other life forms and in conflict with others of our own kind, that we have suddenly gone beyond the pace of biological evolution into cultural evolution and scientific discovery. 

 
What is this new cognitive capability and why does it have such power? 

It seems to me that the power of language comes from the need for parallel-to-serial conversion. When we express our thoughts to another person we must concentrate our attention to choose words that express sequentially the various attributes of thought we wish to communicate. The listener must likewise concentrate his attention to select the appropriate meanings from among many possible interpretations. When I say that something is awe-full I might mean that it is impressive, or that it is unfortunate, or that it is excrement. 

We are not aware of the parallel nature of these associative processes since our attention is only on the selected product; their high data rate capability goes down the drain with the wealth of alternatives that are rejected. One aspect of humor is the satisfaction that comes from resurrecting some of these lost gems with revealing double meanings. 

Paradoxically, the use of a lower data-rate channel brings about a more explicit awareness of our own thoughts and narrowing our span of attention makes possible greater subtlety of meaning. 

In addition the demands of expressing our thoughts so that another person can follow them are so stringent that we even forget their origin in ourselves and concentrate on seeing ourselves as others see us. What we think of as "thought" is cast in the mold of verbal communication. Scientific explanations, as we teach them and learn them, are a cause-and-effect chain of reasoning that we might use to persuade someone so that they will be motivated by the same conclusions we have drawn. The utility of cooperative action is so great that our awareness of thought, and thought of awareness, has developed almost entirely in the social context of communicating our mind-set to other people. 

Nevertheless we recognize that scientific progress comes from serendipitous observations that demand new explanations and from intuitive leaps of conceptualization. Both of these are intrusions of parallel processes into our serial thought patterns. 

Sometimes these conceptual leaps are long overdue and are immediately recognized as valuable; more often the giants of thought are way ahead of us. For example James Clerk Maxwell, who invented radio waves theoretically fifty years before they became a practical reality, analyzed an automatic control system in a paper published by the British Royal Society in 1868 about the behavior of the flyball governor for regulating the speed of a steam engine. It was not until the 1920's that this understanding was applied to marine steering systems and by the 1940's it was included in every electrical and mechanical engineering curriculum and automatic control systems were everywhere; we now have power steering in nearly every truck and automobile. 

Back to psychochemistry: 

Mind Matters by Michael S. Gazzaniga is a popular review, addressed to the intelligent lay reader, of what is known about brain functions and their relation to the subjective experiences he calls "mind". He starts with the experience of pain and explains that more is involved than nerve signals to the brain that let us know about impending injury. Our perception of a particular stimulus as painful depends on our cultural expectations as well as our prior experience and medications we might use. The feedback control mechanism that keeps us from physical harm is fine-tuned with psychochemical and social interactions that we take for granted except when they go wrong. 

 
He describes the pharmacological actions of various substances that have been investigated using patients with different pathologies as well as with animal experiments. Many natural chemical effectors have been discovered and found to be important in particular functional systems, and to be affected by particular medications. 

He goes on to relate what has been discovered about brain functions relating to speech, mainly from patients with localized brain damage. It appears that speech functions are usually localized in the left hemisphere of the brain while spatial functions are on the right, and the recognition of words and the interpretation of meaning seem to be separate functions. 

Roger Sperry was Assistant Professor of Anatomy at the University of Chicago in the late 1940's and he was doing experiments to check the conventional wisdom of developmental explanations for anatomic facts. For example it was assumed that innervation was functionally selected by learning processes after finding its destination. Sperry transplanted legs to unusual places on young salamanders and found that the nerve bundles somehow found the new destination, provided that the transplant was done at an appropriate time. It was also assumed that mental activity such as pattern recognition could be discerned from EEG waveforms and spatial patterns. My friend Ron Myers, a medical student who lived in the student coop where I did, who worked in Sperry's lab placed platinum wires through the brains of cats after they were trained for visual discrimination tasks. The EEG patterns were then completely different but performance was unaffected. 

With this kind of iconoclastic behavior he did not get tenure at the U of C, so he went to Cal Tech where he later got the Nobel Prize for work started in Chicago with my friend, first with animals and later with human patients. 

I am referring to the split-brain experiments, where by cutting through a bundle of fibers called the corpus callosum, the two hemispheres of the brain continue to function independently of each other. First with cats and later with human patients the psychochemical results of mental activity could be explored by detecting their effects in the opposite hemisphere. 
 
Michael Gazzaniga was the neurologist who worked with Sperry at Cal Tech using patients whose intractable epileptic seisures were relieved by the split-brain operation. In these patients the existence of an automatic interpretive function is easy to observe. The visual field is divided with a projector that shows different images to the areas that are received by each hemisphere of the divided brain. An example quoted in the book has a chicken foot shown to the left hemisphere and a winter scene to the right. From a pile of pictures the one hand picks out a chicken, and the other picks out a snow shovel. When asked why, the patient answers, that is a chicken foot and you need a shovel to clean out the chicken shed. The right hemisphere associates snow with shovel, but the left explains the choice verbally with a completely different connection. 

In another example the patient is shown a movie of people in a dangerous situation of fire and violence, projected to the right hemisphere field of view. She responded, "I think I just saw a flash, maybe some red trees like in the fall. I don't know why, but I feel kind of scared. I don't like this room, or maybe it's you getting me nervous." Here the emotional tone was psychochemically communicated, without the content that caused the feeling. 

 
A favorite demonstration in introductory psychology classes is post-hypnotic suggestion - the hypnotist instructs the subject to do something innocuous, for example to get up and look out the window, at a pre-arranged signal, for example "when I pick up this pencil", with the instruction that he will not remember these instructions. After the hypnosis demonstration is supposedly over the hypnotist gives the signal and the subject does what was suggested. When asked why he did it the subject always has a rational explanation. "I thought I saw a bird fly by and I wondered what it was." or "It was stuffy in here and I tried to open the window." 

Everyone but the subject knows it was post-hypnotic suggestion, but the important point here is that the subject rationalized the action for his own benefit and does not know that his explanatory knowledge is created after-the-fact. We are so accustomed to choosing the image that "makes sense" after-the-fact for cognition of our surroundings, and to having a cause-and-effect purpose to explain our actions, that we easily assume its precedence. 

It turns out that the subjective experience of "knowing why" is in fact part of the cognitive process of constructing an internal representation of external reality, which is never finished. We are always imagining what to expect out there and checking whether we are right; we correct our impressions as needed to agree with reality. Whenever we explain our actions we are recasting these impressions into a serial form for the sake of communication. We use the cause and effect mode of explanation which assumes a purpose and a result. 

This personification is so automatic that we use it even when the explanation is only part of our own cognitive process, using the sequential mode only to clarify our thoughts. We are so used to abandoning our first impressions in favor of more plausible images of the external world that it seems natural that an after-the-fact rationalization of our own intentions should be the best explanation. We really believe it when we explain ourselves, but everyone else should keep an open mind about it and judge for themselves! And they do! We might benefit from an open mind and a second thought as well. 

In a nutshell, our subjective experience of rationality is largely an illusion, born of our cognitive need-to-know and our habit of sequential conscious thought. Everyone has the same illusion, but our thoughts are driven by feelings and associations that are bound to be different. 
 
 

Roger Sperry, in his book Science and Moral Priority, goes a step further to assert that our awareness of purpose and the psychochemical correlates of arousal and human motivation are emergent phenomena in their own right. Any effort to understand human behavior and its effects on our society and our world must take account of perceived value systems, and our concern with value systems must recognise the nature of our motivational processes. 

He advocates "a new mentalism" of as-yet undeveloped scientific ideas and methods that takes account of these interrelations without the Dualist separation of mental from material phenomena. We don't need a separate spirit world to find spirituality in our everyday experiences, but we need a new vocabulary to avoid getting lost in a web of magical expectations. 

 
Can we use these ideas in our understanding of today's world? 

The news brings home examples of tribal behavior, in Africa, in Bosnia, in Lebanon, in Afghanistan where that psychochemistry of motivation is effective. Fear and killing out of fear are used by coercive institutions, and theocratic states are the worst. 

The various Orthodox Church institutions were state-supported in Communist countries in spite of the official Atheism, probably to keep them under control. Can we generalize from today's news that their institutional motivations had the effect of sponsoring a tribal mentality in their followers? 

Do we see a different character in the American churches that compete for followers without state support? 

Should we be glad that commercialized spectator sports are so popular in the place of more sinister tribal behavior? 
 
 
 

The Astonishing Hypothesis - The Scientific Search for the Soul by Francis Crick has just appeared in the bookstores. You remember Watson and Crick who won the Nobel prize for working out the molecular structure of DNA forty years ago. He has since worked in the field of neurophysiology and this book is a review for the lay reader of the details that are known about visual perception and consciousness. 

He starts with a warning that there is no miraculous cure for our ignorance, just a hopeful start in working out the miraculous subtlety of living systems that have evolved. He ends with an expression of faith that this is the ultimate truth. 

 
The book reminded me of Chance and Necessity by Jacques Monod who in 1970 wrote a popular book about the nature of life and genetic evolution. The bulk of the book is detail about molecular biology, but a gem of an idea is expressed there. 

Monod said that life is "epigenetic" and "teleonomic".  The process of evolution works out with fantastic subtlety the ways that life forms can grow out of the nature of their materials, analogous to the order with which atoms fit together in inorganic crystals. By "teleonomic" he means the purpose that we see in adaptive variations. He points out that our recognition of organization and purpose in natural systems is a creative act on our part. We should take credit for inventing the ideas that we use to understand nature instead of postulating a miraculous Creator. 

Posted 1 August 1998 by Glen Sandberg

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