M I N D S ,   M O D E L S ,   a n d   M I R A C L E S

Charles Darwin appreciated the creative power of natural selection.

It was evident in paleontology - the fossil history of life on Earth, and in his observations of the divergence of contemporary living species.

Today we see natural selection in many places besides genetic evolution.

In our immune system antibody molecules are produced by cells in our blood stream that are self-selected to proliferate, by their reaction to foreign body antigen molecules. Gerald Edelman got his Nobel prize for his work on the biochemistry of this adaptation. 

In anatomic development, especially in the nervous system, cells proliferate and then die unless they make the connections to become functional.

Neural networks adapt by natural selection. With about 100 billion neurons in the central nervous system, each making connection to about a thousand other neurons, interconnections are reinforced if the association has value, and attenuated if not.

Computer programs are written to simulate neural networks. Multiple inputs are each associated with multiple outputs with links that vary in strength, at first randomly but with adjustments that are increased or decreased according to the success of each trial, in a training process that accumulates corrections from many trials. This kind of learning system has application in self-adjusting automatic controls and for recognizing corellations in systems that are too chaotic for ordinary analysis.  But except for the simplest applications our contemporary electronic computers are almost useless for modeling the massively parallel processing in our brain.

For millennia philosophers have been mystified by what they call the mind-brain problem.

They could theorize about the character of real things, and their interaction, and they could describe their inner experiences but what kind of reality was that?

Our perception of ourselves and of our surroundings is not a "physical thing" but it obviously exists, so it must exist in another domain, call it "spirit". But these separate domains obviously interact. We perceive things and we manipulate them. In fact our body is a thing and we trigger its muscles to manipulate it, and tools, and other things. We even perceive a tool as an extension of ourselves, and feel the force of the pliers on the object we are gripping, or the impact of the tennis racquet on the ball. Yet the perception is obviously different from the physical fact. How does that work?

Today we have clarified our thoughts about information and how we can use it to wend our way and work our will in the world. 

The ventilating system in this room has a very simple central nervous system.  The thermostat processes one bit of information - one binary digit that signals when the temperature is above its set point.  That signal turns on a cooling system and then turns it off when the room temperature is below the set point and the signal disappears.   We understand the working of that system as a process- the rudimentary experience of the thermostat  results in behavior of the system to regulate room temperature by using an external source of energy. That system was created with a purpose - by its Intelligent Designer - to keep the room comfortable.

Experience and behavior and purpose are ideas that we use to comprehend what happens.

What was mystery to Plato and Aristotle, and Descartes, and Kant, and Whitehead is now, more and more, empirical fact. What was speculation to William James and Donald Hebb is now neuroanatomy and physiology. Take for example our system of visual perception. In the 1950s it was established empirically that fibers in the optic nerve don't carry point-by-point signals from the optical image projected on the retina, but rather are stimulated by abstract features of that image. The retina of the eye is part of the central nervous system, with associative neurons that connect to a variety of combinations of the surrounding rod and cone cells that are sensitive to light. They detect patterns of signals that represent features like edge contrast and geometric orientation and brightness or color. The impulses through the optic nerves to the brain represent patterns, not points in the visual field.

In the brain there are at least seven regions that receive signals, directly or indirectly, from the optic nerves. They specialize in different aspects of pattern recognition - object/background, motion, perspective, hue and shade of surfaces corrected for differences in illumination, and so forth. They are triggered by patterns of patterns and they feed into one another to create the images in our brain that represent our surroundings. I'll try to show you an intuitive idea of how that works. 

What is pattern recognition good for?

Each associative neuron is constantly combing its inputs for a combination that it recognizes, and it says "Aha!" by sending a signal to the multiple neurons that connect to its output.  They receive this input and many others.  And they say "Aha - I recognize that combination of edges and surfaces - it might be a table." And that output triggers other neurons that say "If it is, then it has these characteristics." And other neurons that say "If so, it is. If not, it must be something else."  This roundabout way of discovering reality works so well because each associative neuron is self-motivated, checking its inputs and waving its outputs, working in parallel with billions of others.  And when a combination of stimulative and inhibitory signals causes a useful output that combination  is reinforced, and can be more easily recalled.  Thus we build up a memory of past experiences that feed back into our recognition of present inputs in what Edelman calls a re-entrant system. The associative character of that information storage and retrieval yields the fantastic wealth of possibilities in our thoughts about experiences, real or imagined.  And the magic of intuitive leaps to new ideas that we create.

So all we know of an experience is the thoughts it stimulates.  Therefore recalling the thoughts recalls the experience.  But the thoughts are information and the experience is its display in our mind - rerunning the associations that give access to their whole context.

Let's realize that our perception is a fantastic process of pattern recognition - fantastic because we can indulge the fantasy of what might be, related to what we perceive. We automatically fill in the blanks in our visual field, the blind spot where the optic nerve exits the eye and where blood vessels cross over the retina. (The retina of the eye is anatomically inside out! The light-sensitive cells are on the outside and the connecting nerves and blood vessels are inside toward the lens!) We use our knowledge from past experience of familiar objects to recognize the whole object, not just the part that is visible from a particular viewpoint, and we correct the image automatically for the motion of our eyes. We see what's there, and what it's doing, not just the fragmentary image in our eyes at any moment. We are modeling our surroundings in our brain.

A model is a representation of something else.

A ship model is a miniature construction that communicates a reality that is too big to fit in the museum. A model of behavior is an example that embodies an ideal. A dress model is an idealized wearer of the product.

And in science we recognize that our ideas about real things and processes are idealized representations - they are models of reality.

Isaac Newton thought he discovered the Word of God.

Causality is a human experience. The leader would command and the followers would obey. Creation is a human experience. We wish to make something and that's motivation to do the job. God said F=Ma and that's how His Creation had to go!

Newton's creation was more subtle. He invented the methods of Calculus to deal mathematically with continuously changing variables. He could solve the equations of motion of planets around the sun and explain their variable velocity and elliptical orbits that Kepler had deduced from astronomical observations.

Nowadays we think of Newton's equations as a model of reality - an idea that applies perfectly to ideal systems - point masses and instantaneous action at a distance - and real objects and mechanical phenomena are near enough to the ideal that the equations are useful. We can predict mathematically, to good accuracy, what to expect given input data about the system.

The modeling function serves a purpose - EXTRAPOLATION ! We can imagine what-to-expect from sensory inputs and past experience. We know where to go to catch that fly ball when it comes down.

How do we know? The associative connections in our massively-parallel-processing system call back aspects of past experiences and fit them together into our ongoing imagination of what-to-expect.  We know that that fly ball will continue on its trajectory unless something gets in its way.  And that experience is dynamic because it is constantly updated by new sensory input as we zero in on the effective motions to catch the ball.

We automatically forget what was wrong in our perception of reality and replace it with the latest information. We, and other life forms, have evolved the scientific method! We theorize (imagine) what to expect, compare with empirical data, and correct the theory so that it better models reality. The common fly, with very different optics, or a bat in the dark, flying by sonar, can approach and land wherever they want to.

Another example of modeling will clarify our thoughts about reality, and the reality of our thoughts.

Architects don't do architectural drawing any more, except for casual sketches to develop their ideas. They use computer programs that compile lists of data about their creation - locations of points and lines and surfaces in the construction. That input is facilitated by a human interface - a part of the program that displays on the screen an image of what the data represents. When the job is done the computer uses the data-list model to drive a plotter to create working drawings to represent the project, with dimensions and specifications for construction. And perspective drawings with shading and rendering of surfaces and surroundings to visualize the completed project.

A related application is called virtual reality - a program that accesses the data about a project and creates an image on the screen of what it looks like from any viewpoint, inside or out. We can walk through the building and see it as it will be when finished.

An even more impressive example of virtual reality is used in flight simulators and video games. The user wears goggles with binocular images, which are rigged to signal the computer about the user's head position. The resulting images change automatically as the user looks around at the virtual reality represented by the computer model.

But the map is not the territory, as the General Semantics people tell us.  It's information about the territory, incorporated in a physical form of paper and ink.  Or in the GPS system you might have in your car, that calculates your location from satellite signals and refers to map data to create an image of the roads you might take from where you are to where you want to go.

So we see that this visual modeling process has three components - data to represent the reality, an implementation to view the data, and a user to react to what he sees.

Newton's laws represent planetary motion with a mathematical notation F=Ma where force F is proportional to the product of planet and solar masses and the inverse square of their distance apart, and acceleration a is the rate of change of velocity which is the rate of change of position. The implementation of that model is a solution of the equation that evaluates the vector position of the planet as a function of time. The user is an astronomer who points his telescope to see the planet, and perhaps makes measurements to improve the accuracy of the input data.

And evolution by natural selection is an idea, a model that represents the development of a population of individuals that replicate, with differences, in an environment that affects viability. The individuals might be microbes, or plants, or animals, or the neurons in your brain, or the connections between neurons. The user is a paleontologist classifying fossilized life forms, or an environmentalist observing the interaction of different life forms, or Gerald Edelman puzzling out the adaptibility of our immune system or the creativity of our "imagined present." 

Consciousness and awareness and experience are separate functions.

Experience is the raw input to our thought processes, sensory and somatic and instinctive and retrospective, mostly unconscious.

Awareness is the parallel-processing pattern recognition system that creatively models our circumstances, external and internal, for instant response. It manages so much that we can't possibly attend to everything consciously.  It enables access to a wealth of inputs that might be relevant, by directing our sense organs and filling the blanks from past experience, and spinning a web of possibilities to be considered.  Memory and extrapolation from past experience and intuitive leaps to new ideas can be realised.

Consciousness is the motivation-modulated, selective attention that guides our way in the world.  It's our awareness of purpose, which we share with other animals.  It's our effort to reach a goal or to accomplish a task.  It's our train-of-thought, cause and effect reasoning.  It's our awareness of thinking, and of how we might communicate our thoughts to others.  It's our ability to see ourselves as others see us, so that we can decide what to say, to lead them to the thoughts we want to communicate.

Our virtual model of reality uses input data, Experience, with an implementation, Awareness, and a user, Consciousness, to selectively and interactively serve our purposes,

Now let us get back to the quandary we started with, what's the difference between thoughts and things?

First, the map is not the territory.  But all we know about things is the thoughts we have about them, the signals they generate in our perceptual systems and our active, imaginative and creative conceptualizing about them.  And so if all we know is what we think, of course we think we know it all!  However lets take credit for the job that is automatic in our mind and recognize that our recognition of things as different from thoughts is part of our own Intelligent Design of the world as we know it!  It's a fait accompli that is so fundamental that it's taken for granted in our everyday lives and when philosophers consider the question they turn it upside down and put thoughts in a mysterious unreal world along with spirits and souls and gods!

The ancient philosophers were concerned about the "essence" of things, what we today would consider the definition of the words we use to classify them.  The idea of "dog" has a more fundamental "existence" than any particular dog because it is more abstract, it is simpler because the differences are left out of its definition.  Now we are much more sophisticated about that data processing. We can use words to represent things, or attributes of things, or processes that happen to things. And our ideas about those things, attributes and processes.

More Thoughts

In fact there is usually a survival value for variability between individuals, to enable a population to adapt to changes in the environment, or to help your pattern recognition capability to learn from experience.

Modern Physics (1890-1920) - the discovery of ionizing radiation and sub-atomic particles and relativity - found that fundamental ideas about the immutability of matterand space were not universally applicable. Any idea is only good for what it's good for, and we can expect to need new ideas when we discover - or create- more reality.

Process Theology has developed the idea of a God that's not omnipotent and omniscient and supernatural, but rather is an idea that we can use to comprehend what is real.  Our whole knowledge of reality is a process, and we're missing opportunities for a wider horizon if we don't keep an open mind.

This time it's an effort to build an intuitive understanding of our capability to experience by creating an internalized representation of our place in the world.  The massively parallel computation in our brain is taken for granted and we're exploring what it's good for without resorting to supernatural, magical thinking.

And the quandary of mind-brain dualism is left behind in the trash bin of word games that philosophers play on one another.