More on Mind

Dateline: January 11, 1998

WHAT does mind consist of? It consists of intellect, intelligence, awareness, consciousness, subconsciousness, and (arguably free) will. Probably a bunch of other very important stuff, too, such as emotion, curiosity, and imagination; but the others seem to me the fundamental elements, and form the focus of this article.

Intellect is the power of knowing as distinguished from the power to feel and to will. Awareness is the recognition that one is not a brain in a vat--it is the ability to feel, to sense, that there is a world outside. Consciousness is the obverse: the recognition that one is an individual mind in a body in an environment, or as philosopher David Chalmers has put it more succinctly, it is "the subjective experience of an inner self." (I have a careless tendency, stemming from the days before I got into this stuff, to use sentience as though it were equivalent with consciousness. Dan Dennett defines sentience as the "lowest grade" of consciousness. I now rather think of it as the lowest grade of awareness. Whatever the case, sentience is not to be confused with sensitivity. A thermostat is sensitive but not sentient.)

Armed with consciousness and awareness, a survival machine has no choice but automatically to want (to will) to make greater sense of its surroundings and develop ways to deal with it. (In a sense, the apple from the Tree of Knowledge endowed Eve and Adam with the worldly attribute of physical awareness--worldly because it implies sensors and therefore a body. Pure spirit, lacking physical sensors, would be unaware of and impervious to temperature, walls, pain, etc. It suggests that Utopia/Paradise/Nirvana/the Garden of Eden is unattainable as long as we are aware. You'll have to consult the Buddhist monks if you want to know how to attain Nirvana without getting naked and knowing it.)

Though I leave out imagination from my list of fundamental mind elements, I have to agree with Ian Stewart and Jack Cohen that if there is a single most important "essence" of mind, it is probably imagination. Because the fact is, everything we see, hear, touch, and smell is essentially imagined. The physical components of the brain construct an approximation of the physical components of the world. There is no red or blue in nature, merely narrow bands in the electromagnetic spectrum for which our brains construct an imaginary sensation we label redness or blueness. It's not that reality is a figment of our imagination, it is that imagination is a figment of reality, as Stewart and Cohen would say.

Digital or Analog?

Is mind digital or analog? This is an important question, not least because Machina sapiens is, at least to begin with, a digital being. Is mind, on the one hand, all or nothing, on or off? Or is it, on the other hand, a matter of degree? Does a bacterium have a little bit of mind (or a mind with very limited capabilities), an ant a bit more (or somewhat more powerful capabilities), and a human most of all (or the most powerful of all)? Dan Dennett (in Kinds of Minds) opts for analog, being doubtful that we will ever discover--or would even want to discover, for ethical reasons--a line separating the sentient from the non-sentient.

Dennett is among the many who, over centuries, have believed that mind resides in the whole body, and not just in the brain, despite the thrall in which Descartes' mind-body dualism has held both science and philosophy. Descartes had not the last nor the only word. Friedrich Nietzsche wrote in Thus Spake Zarathustra: "Behind your thoughts and feelings, my brother, there stands a mighty ruler, an unknown sage--whose name is self. In your body he dwells; he is your body. There is more reason in your body than in your best wisdom."

For an example of your body's mind in action, take blushing. No-one ever wants to blush, and usually our conscious mind tries to override our body's embarrassing decision--but to no avail. Or take a pilot's swift bodily response to a sudden emergency, hauling back on the stick before s/he has time to think. Yes, it takes time to think.. Roughly a twentieth to a tenth of a second for the pilot's consciousness to register that immediately in front of him or her is a 747 emerging through a gap in the clouds and on a collision course. In that split second, assuming a combined speed for both aircraft of about 1,000 mph, between them they travel roughly the length of a football field. If you're a passenger on either of those planes, the last thing you want is for your captain to mentally dust off the flight manual in memory and turn to section 37(C)iii(q), "Collision Avoidance."

How does the pilot react to the menace without being fully aware of it? Francis Crick (co-discoverer of DNA) and Christof Koch wrote in Scientific American that "It now seems likely that there are rapid 'on-line' systems for stereotyped motor responses for hand or eye movement." My take on this is that our bodies come with a built-in secondary mind that monitors the environment and that takes control from the primary mind when triggered by an immediate threat to survival.

Kinds of Minds

Dennett classifies minds into four types, which I have taken considerable liberties in interpreting thus:

Darwinian minds are physically and mentally blind. If they stumble across the right behavior, it is by pure chance. Pre-biological crystals and the most primitive biological lifeforms exhibit such minds.

Skinnerian minds are mentally blind, and seek for the right behavior by physically trying out whatever options are open to them. Primitive lifeforms and certain types of robot, such as Braitenberg vehicles, exhibit Skinnerian minds.

(At this point, we seem to go from a basic algorithmic mind process to a heuristic one.)

Popperian minds first try out the options in their minds, applying heuristic "rules of thumb" before committing to action. The higher animals appear to be Popperian, and we have built robots with embedded heuristics.

Gregorian minds try out their options in the group mind, looking for pointers and tools to help them make a decision. The group mind--the family, the tribe, Society--is dependent on language for its existence.

Humans evidently have Gregorian minds. It is open to debate whether monkeys, dogs, dolphins, and other animals that seem to exhibit a high degree of intelligence have rudimentary intraspecies language capability and can therefore be said to have Gregorian minds. It seems to me also open to debate whether composite organisms such as bees' nests and ant colonies have language capabilities-think of the bee's dance, a body language telling the nest where to find food, or the ability of an ant colony to dispatch workers to the far side of the mound to repair the hole left by Ant Hilary (Douglas Hofstadter's anteater in Godel, Escher, Bach). But if there is a communal mind communicating with and controlling the worker ant, where exactly is it? For that matter, where exactly is your mind located?

Where is It?

Mind is not centrally located. It is not in the brain; an ant colony has no brain. Neither is it necessarily a feature of the whole body. It is, in fact, at least at the Gregorian level, a distributed feature, which probably explains why attempts to pin it down to the brain or some organ, some CPU, within the brain have been doomed to failure.

The arrangement of furniture in your home reveals part of your mind. Your automobile is an extension not only of its engineer's mind, but also of the group mind. The automobile is a set of thoughts and concepts--parts of a mind--captured and preserved in a form of organization (in the case of furniture) or in metal and plastic (in the case of an automobile). In fact everything we create is a part and not just a product of our minds. We attribute to our most creative people the possession of "great" minds. How do we know? We can't see inside their heads, can we?

Umm, well, actually, yes, using brain scanning techniques. But we don't need to scan Picasso's brain (or body) to be sure he had the mind of a genius. Geniuses take what's "in" their minds and hang it out on display. They distribute it. If Picasso had never put brush to canvass, he would not have had a great mind. He might (though even this is doubtful) have been capable of conjuring up his wonderful works "in his head," as it were, but he could not have conjured and retained all of them in his internal memory. His canvasses are in fact part and parcel of his mind, his memory--his memes.

A Penny for (a Videotape of) Your Thoughts

Why do I write "videotape" and not "photograph" in the above subhead? Because a thought is not a still image. It is a moving, dynamic thing and--wouldn't you just know it!--someone's figured out how to tape it. It's humiliating, especially to one who hasn't yet figured out how to tape a TV program on his VCR.

Probably the hottest thing in neuroscience right now is brain scanning, using such techniques as magnetoencephalography (a ME-scan! How appropriate!), 3-D electroencephalography, functional magnetic resonance imaging (fMRI) scanners, positron-emission tomography (PET) scanners, magnetic resonance spectroscopy (MRS), and the "PET reporter gene/PET reporter probe," a device so new (as of 1996) that Tom Wolfe (author of The Right Stuff, a best-selling book about test-pilots) noted "it still has that length of heavy lumber for a name." These machines do all manner of things, from mapping the blood flow and chemical changes in the brain to showing a video of specific genes in real time as they are expressed inside the brain. Some of these devices were barely on the technological horizon five years ago. In another five, they'll be considered crude and quaint.

Geoff Aguirre at the University of Pennsylvania has used fMRI on subjects immersed in a virtual reality world, enabling him to test a much greater range of thought-processing mind/brain activity than is otherwise possible for a patient pinned motionless inside an 11-ton magnet.

A ME-scan enabled neurobiologist Karl Friston to map a subject's brain activity as the subject decided to make small hand movements. The scan showed what areas of the brain were involved, and when, and that it took the subject more than a twentieth of a second between deciding to move his hand and actually moving it. This is why you don't want your 747 pilot making primary-mind intellectual decisions within a hundred yards of the side of a mountain.

Science writer John McCrone is so taken with the dynamical mind process that he is taking a year to write a whole book describing about a twentieth of a second of it (Going Inside: The Science of a Single Moment of Consciousness, forthcoming October 1998, London, Faber & Faber). After you've read the book (and you should-he's a good writer), then go see the movie.

Tom Wolfe, on the other hand, is somewhat less than thralled over the potential of neuroimaging (to use the academically preferred word for brain scanning). Writing in Forbes Magazine, Wolfe acknowledges that neuroscience is likely soon to produce a new theory as powerful as Darwin's, but he fears that brain imaging . . .

The "certain theories" to which he alludes cluster around one central theory originated by zoologist Edward O. Wilson: That we are hardwired genetically to be what we are and behave as we do. Therefore, think some of the theory's believers, we really are machines, therefore we have no free will, therefore it's OK to do drugs, be gay, sexist, violent, ignorant, etc. etc., and I can prove it Your Honor with this home video of my latest PET gene scan. The only relief offered by this scenario is that lawyers would become extinct, it being so obvious we're all not guilty of anything.

Fortunately for my own sanity I don't subscribe to such an extreme version of the theory and neither, I am sure, does Wilson. (Lawyers, however, should not take comfort in that. There remain other reasons why the days of their profession are numbered.) It's not difficult to accept that hardwiring at least for the Four F's (Fighting, Fleeing, Feeding, and Mating) is present, if not yet fully expressible, in the newborn infant; but the intellect, which has the power to override the hardwiring or even to re-wire it in places, is put there by the environment, particularly the immediate social environment of the family. It is not innate, it is not genetic. It is memetic.

I do, however, go along with the theory so far as to think we are complex machines, or if you want to be persnickety about definitions, that we are complex descendants of simple machines.

Emergence

There is a school of thought, to which I subscribe, that life and mind are not fundamentally complex, but instead evolved through and are made up of lots of very simple, algorithmic, on or off, mindless, robotic agents, and that through some synergistic mechanism (Boole's logical operators AND, OR and NOT being prime candidates for the parts making up this mechanism) they tend to bring order out of chaos.

A striking demonstration of this effect was provided by roboticist Philippe Gaussier in 1994 using a bunch of very simple, algorithmic, on or off, mindless robots known as "Braitenberg vehicles" after Valentino Braitenberg, the neuroscientist who conceived them. A Braitenberg vehicle is a robot with two light sensors (photocells), one on the left and one on the right. Whichever of the two sensors picks up a stronger light signal, the robot will turn in that direction and move toward the stronger light source.

Francesco Mondada built some tiny Braitenberg vehicles, giving them three wheels, a motor, and the left and right photocells. (He called them kheperas, Italian for scarab beetle, which I guess they resembled.) The photocells detected light reflected from the four walls surrounding the kheperas and served effectively as collision avoidance mechanisms. As a khepera approaches an object (another khepera or a wall) the reflected light grows stronger and the khepera will turn to move in another direction. Simple. Algorithmic. Mindless. Robotic.

Gaussier scattered a bunch of upright pegs (on bases so they wouldn't tip over) at random on the kheperas' table top, and gave each khepera a little shallow horizontal hook at the back that would temporarily latch onto any peg that happened to be in the way during a turn, drag it around for a bit, and then let go of it when the khepera turned in another direction. The pegs themselves, when approached frontally, would cause the kheperas to turn away. This setup is random. It is pure chance whether a peg gets hooked and deposited, and you'd expect that at the end of any given period of time the table top would look just as chaotic as it did to start with.

Not so!

Over time, Gaussier's kheperas "shepherd" the pegs into neat rows, some at right angles to others, to form a maze. To the kheperas, the rows of pegs look like a wall. Once the maze is complete, the kheperas spend their time wandering around it without disturbing the walls. They not only change their random environment into an orderly one, but also in the process are forced to change their own random behavior into a more orderly set of movements. Order emerges out of chaos, driven by Darwinian mind.

The key indicator of the value of a scientific theory is its "explanatory power," its ability to explain how and sometimes why something is what it is and does what it does. It seems to me that Gaussier's experiment, which is a hardware manifestation of software forms of artificial life/cellular automata, is a potent demonstration of the potential power of the theory of emergence starting to . . . . . . emerge out of the study of chaos and complexity. The khepera universe is arguably (yes, arguably) deterministic, but it has the hallmarks of a Darwinian mind.

God and Gaussier play dice. The dice are not loaded, but the table--the universe, the phase space--is. It is dynamically warped by strange attractors.

Until next week,

 

 

 

 

NEXT WEEK: Machine Translation 2. A review of SystranPRO English - Japanese tranlsation software.

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