|A book by|
William H. Calvin
UNIVERSITY OF WASHINGTON
SEATTLE, WASHINGTON 98195-1800 USA
The Cerebral Symphony|
Seashore Reflections on the
Structure of Consciousness
Copyright ©1989 by William H. Calvin.
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Thinking about Thought:
Twilight at Nobska Lighthouse
Perhaps our thinking exemplifies a selective system. First lots of random scattered ideas compete for survival. Then comes the selection for what works best -- one idea dominates, and this is followed by its amplification. Perhaps the moral... is that you never learn anything unless you are willing to take a risk and tolerate a little randomness in your life.the American physicist Heinz Pagels, 1988
The Eel Pond drawbridge is out of commission. The hydraulic brake (it gently lowers the bridge the last meter or so) leaked its fluid, and so the bridge crashed down, damaging the gears. They're talking of two weeks just to get the parts. In the meanwhile, boats are trapped. They've gotten a big construction crane to come out and hold the bridge open for several hours at a time yesterday and today, to allow boats in or out. And, of course, expose the graffiti on the bridge's underside for two hours at a time, rather than the usual two minutes; while high school sports and sex are the usual topics, the most legible from down the street is Entropy Rules -- the End of an Era. Weltschmerz in Woods Hole? But certainly appropriate to this new situation, with the breakdown of carefully engineered order in this local region of the universe.
With the two-week prospect, the question has arisen as to who will pay for the crane. Two of MBL's big fishing boats dock inside Eel Pond, alongside the animal tanks, and so the MBL's strained budget may end up paying for the crane if the town of Falmouth reneges on its responsibility to keep the sea-lanes clear of the obstruction it engineered.
Prop the bridge open? A little temporary scaffolding is the obvious solution. There is a back way around Eel Pond to reach the rest of Water Street; the bridge isn't the only route. But some merchants will feel cut off from the waiting-for-a-ferry pedestrians if the bridge is propped open. If the town can even contemplate leaving the bridge closed shut for two weeks, one can see that the ancient presumption of the boat's right-of-way over imposed obstructions has been seriously eroded. Lawyers love such situations.
WITH THE CHANGE IN SEASON (autumn is almost "in the air") have come more of the great birds as they fly south from Maine: Not only does Eel Pond now have five cormorants sunning themselves on white buoys, but a Great Blue Heron flew in several hours before sunset. He perched on the outboard motor of a small boat, then moved over to repeat the same pose on the rear of a cabin cruiser. I kept watching to see what would happen if someone came up the passageway from below decks -- and saw that giant bird perched there, looking at him. The Great Blue looks even taller than usual, as one typically sees a heron standing in a foot of water, looking for foolish fish in the shallows.
He's quite out of place here, though his ancestors might have fished these waters a hundred years ago. Great Blues specialize in shallow water fishing (they'll take the occasional snail or tadpole as well). Thanks to all the rock and concrete that has eliminated the former shoreline, Eel Pond doesn't have much shallow water, and derelict boats occupy most of what there is; that heron will either have to start competing with the cormorants at their deeper water game, or fly elsewhere to find a more suitable stretch of shoreline. As the ecologists put it, the cormorants and the herons have "partitioned the resource" (by depth of water, in this case) rather than competing directly with one another; if they competed directly by fishing the same waters, one species wouldprobably win out and the other go extinct. The basic reason that so many animal species are going extinct these days is because humans have invaded their niche and started competing with them for resources such as food and land. Usurping their food and nesting sites is just as deadly as shooting them, merely delayed one generation.
Maybe this is a nonconformist heron, out to change the traditional heron habitat. But most genetic or cultural changes that carry an individual very far away from the optimized way of making a living are going to be bad news: even if he manages to feed himself, he is likely to be judged a poor risk by traditional genetically programmed standards, and therefore lose out in the competition for mates. Once optimizing has gone on for awhile, it can create a dead-end (at least, until the climate changes, un-optimizing things).
It's closely related to one of the arguments advanced for why humanlike consciousness-intelligence-language-whatever has only happened once in 3 billion years: Maybe it was selected against, because little increments would not really be net improvements in the reproductive sweepstakes called "fitness." Just imagine a chimp that "talked a little funny" or didn't learn to forage efficiently because of spending so much time playing around with hammers. Of course, a sudden and big improvement, which carried fitness changes into net positive territory, might get around this ecological niche-fixity objection. Jumps can occur, thanks to conversions of function -- and once a new niche is discovered, natural selection may be relatively ineffective until the niche is saturated and optimizing begins. So little improvements may not be the best place to look for the origin of these human peculiarities, however important efficiency eventually becomes.
LABOR DAY in the first week of September is giving sure signs of being the official end of summer. The town is full of overstuffed station wagons, waddling about. And the skunks seem to know about the refrigerators being cleaned out. Several of the restaurants and taverns in Woods Hole have already closed for the season.
Rented trucks are much in evidence in the MBL parking lots as labs pack up and go back to New York or Baltimore or Pittsburgh. There is a new seasonal traffic hazard, thanks to amateur truck drivers: I saw one sad rental truck stuck between two cars, having clipped both of them while trying to drive through a car-width lane in the MBL parking lot. The truck was wedged in tight, embarrassingly trapped for everyone to see.
Eel Pond is almost empty of sailboats, though that surely has to do with the lovely weather as well as people being homeward-bound. There is almost room to sail in Eel Pond or Little Harbor again; ordinarily, they are overcrowded parking lots for boats, a minor version of the tragedy of the commons.
MBL's little patch of beach front is absolutely jammed with bathers. Its parking lot is also crowded, but many of the cars and station wagons are packed for the trip home. The imported sand of Stony Beach seems to be the last stop before hitting the road, a chance to wear out the kids so that they'll nap during the long drive down the interstate highways. Unfortunately, the salt air tends to make the drivers as sleepy as the kids.Today's civilization is full of people who have not the slightest notion of the character or poetry of the night-- who have never even seen the night. Especially away from the city where it is truly night and there are no artificial lights to stab or trouble the dark....the American natural historian Henry Beston, 1928
AS THE PACE OF LIFE CHANGES in Woods Hole, the evenings are different. The haze has been clearing out, probably because the winds have shifted about to blow dry out of Connecticut and Rhode Island, rather than from off the humid Atlantic. It has caused a mass migration of the windsurfing fans to new beaches.
By late August, the sunsets are noticeably earlier -- and the sun sets over Woods Hole as seen from Nobska lighthouse. The promontory in front of the lighthouse becomes a gathering place for the local residents who are fans of the sunset, and each evening the sun sets a minute or two earlier, sets a solar diameter farther south than the previous evening. Until by early September, it is setting right in the "Hole," the east-west channel between Woods Hole and the Elizabeth Islands. In the foreground stretches the bright red streak of shining water; sailboats sail into it, ferries steam across it, and the windsurfing sailors off Nobska Beach seem to disappear within it for a few moments.
And the change in weather has brought some spectacular violet-and-rose sunsets. Occasionally, the lighting conditions and pastel backdrop are just right for seeing green spots near sunset, as the afterimages of the bright sun on the retina are enhanced by color contrast; little green spots seem to stream off the sun and drift to one side. If the sun is too dim due to haze, or the nearby clouds are too bright or not reddish enough, one doesn't see them.
This show is, of course, all a form of perceptual illusion, thanks to lateral inhibition networks in the retina and brain. The green that one sees is the complementary color of the red surroundings; the retina's sensitivity was turned far down by the sun itself, so when looking at ordinary red clouds, the spot appears very dim and the surrounding red clouds, via lateral inhibition, induce the green. But why does the spot move, even when you maintain your fixation on the sun? That turns out to be about like asking why the whirlpools above your bathtub drain move around. Such spots of decreased sensitivity seem to be more a matter of neuronal dynamics than bleached photoreceptors, and the locus of decreased sensitivity can apparently wander away from the fixation point.
THE SMELL OF A LOG FIRE lingers after dusk, here on the beach below the Nobska lighthouse. Remembrance of things past -- the smoke and the salt air combined evoke a constellation of Proustian memories for me.
With the humidity thinning out, there are now clear nights with fine views of the stars. There are three planets in an arc across the southern sky: Mars, then Jupiter and Venus. Below them the beam of the searchlight regularly sweeps, left to right.
And there are some moving stars -- not satellites, just high-flying airplanes on their way to Europe. The popular overnight flights out of New York fly over Cape Cod on their great circle route to London or Paris. A blinking light will appear in the southwest sky above Venus, then move slowly across the zenith and disappear in the northeast, all within about two minutes. As soon as one disappears, another winks into view down in the southwest above Venus. Again and again, this two-minute pattern repeats, as if there were an endless supply of jumbo jets on some New York runway, all waiting to follow this one invisible track in the sky. Sometimes there is a two-minute pause until another appears; I suppose that they represent flights to elsewhere.
I watch for even more slowly moving lights in the sky, the satellites rotating around the earth. Or some fast streaks, meteors decelerating through the upper atmosphere. But the trans-Atlantic planes, cruising on their robotic autopilots, seem to be the only moving lights tonight, like moving trains strung together on an invisible track in the stratosphere.
IT ISN'T JUST CHILDREN that are critical about how a story is told. All human beings seem to be perpetually stringing things together: Phonemes into words, words into sentences, concepts into scenarios -- and then fussing about getting them in the right order. Our brain uses word-order rules to create a very productive language, with an infinite number of novel messages, rather than the several dozen standard interpretations associated with the several dozen cries and grunts of any other primate species. It isn't our mellifluous voices that constitute a significant advance beyond the apes but rather our arrangement rules, the meaningful order in which we chain our utterances.
And talking-to-ourselves consciousness is, among other things, particularly concerned with creating scenarios, trying to chain together memory schemas to explain the past and forecast the future. Peter Brooks describes it this way:
Our lives are ceaselessly intertwined with narrative, with the stories we tell and hear told, those we dream or imagine or would like to tell, all of which are reworked in that story of our own lives that we narrate to ourselves in an episodic, sometimes semiconscious, but virtually uninterrupted monologue. We live immersed in narrative, recounting and reassessing the meaning of our past actions, anticipating the outcome of our future projects, situating ourselves at the intersection of several stories not yet completed.
It is our ability to choose between such alternative scenarios that constitutes our free will -- though, of course, our choices are only as good as our imagination in constructing a wide range of candidate scenarios. Logical reasoning also seems dependent upon the sequencing rules for reliable entailment. Our sophisticated projection abilities are very sequential: A chess master, for example, tends to see each board configuration not just after the next move but a half-dozen moves ahead, as several alternative scenarios. Even our recreations are surprisingly serial.
Darwin Machines suggest that our insightful behaviors arise from scenario-spinning, thinking before acting. It need not even be conscious attention given to a problem, as much problem-solving seems to occur in the background, subconsciously.
HOW WE PIECE THINGS TOGETHER subconsciously has always been one of the great mysteries. The examples in Chapter 5 -- Otto Loewi's discovery, and Albert Szent-Györgyi's aphorism -- emphasize the role of nocturnal mentation. But often the solution to a problem suddenly presents itself when you're awake and seemingly doing something else.
Today, I was sitting on the beach, listening to the waves, doing nothing in particular. And suddenly I knew what was the trouble with our car, which had sprung a leak in the cooling system earlier in the day. Yet the leak stopped after I replaced some coolant ("antifreeze," in the American idiom). It was dripping quite regularly from back under the engine somewhere, a stream running down the street when we were stopped in front of the bakery. What sort of major leak suddenly stops?
But it did. After an hour's drive and a ferry trip (and not a drop of antifreeze under the car after it sat on the ferry), plus a hike down the beach, and finally my subconscious presented the solution to my conscious brain -- after I had been contemplating the incoming tide and the Great Blue Heron.
- I had turned off the ventilation system before leaving the bakery, opening up the rooftop because it was such a nice day.
- Ventilation systems include heaters.
- Heaters have hot antifreeze piped through them.
- But there must be a shut-off valve for the antifreeze, in case you're running the air-conditioning system instead
- Therefore the leak must be in the hose that returns the antifreeze to the radiator. That's why the leak stopped after we left the bakery!.
Now, consciously, I hadn't been thinking about this for several hours; I'd relegated it to something to check out when I returned home. And I certainly hadn't remarked upon the fact that I'd routinely turned off the ventilation system; it was one of those minor facts lingering in my short-term memory that would likely have been completely lost in another few hours. Admittedly, I had remarked upon this being an intermittent plumbing problem and wasn't that novel...? (I have a long history of trying to solve intermittent electronics problems, because they plague the neurophysiologist, and of trying to diagnose intermittent neurological problems associated with marginally conducting nerves -- so intermittent symptoms were automatically placed in an interesting category).
But car problems I usually leave to the dealer's mechanic. I haven't understood my way around under the hood of a car since the 1950 Plymouth station wagon that I bought used while in graduate school. My knowledge of automotive plumbing is minor: I worry about adding windshield-washer fluid to the antifreeze by mistake. But my subconscious figured all this out, presumably by trying out lots of nonsensical combinations of things that were too absurd to complete with my main-track conscious experiences of sun and surf.
My wife, who thinks that theories exist to be disproved, immediately suggested an experiment, that we should turn on the heater when we returned from the beach and look to see if any antifreeze dripped. But then sun and surf got to her too, and we forgot all about it.
Multiple scenarios evolving simultaneously suggests, however, that there is more to Darwin Machines than just the set of railroad sidings, evolving away to create a dominant sequence -- it seems as if there are various collections of sequencers, subpopulations with their own internal evolution. The same thing happens in biological evolution, as isolated subpopulations (demes, as they are called) provide the setting for much competition among themselves. Perhaps our population of a hundred sequencers becomes partitioned; instead of a dominant near-clone taking over entirely, perhaps the minorities get the opportunity to evolve among themselves. And occasionally take over, when a near-clone shapes up that can supercede the original victor.
ONE OF THE MAJOR HAZARDS OF THOUGHT is when a search for the best option is prematurely concluded. Premature closure is easy to spot when it occurs with jut-jawed determination, as in the modern bumpersticker: God said it, I believe it, and that's that! And its opposite, Hamletlike indecision, is also celebrated, as Daniel Dennett notes:
Time rushes on, and people must act, and there may not be time for a person to canvass all his beliefs, conduct all the investigations and experiments that he would see were relevant, assess every preference in his stock before acting, and it may be that the best way to prevent the inertia of Hamlet from overtaking us is for our decision-making process to be expedited by a process of partially random generation and test.
In-between cases of premature closure are usually spotted only after the fact, as we contemplate a mistake.
The most frequent cause of premature closure in children is probably a short attention span. But in adults it is surely the logical framework: When something fits it, you stop surveying alternatives. When I manage to fit throwing into a newtonian framework, I usually stop there and never contemplate the relativistic case. When a doctrinaire economist manages to fit a social phenomenon into a marxist or capitalist framework, he or she usually stops exploring alternative explanations for the phenomenon. In politics, one constantly remarks on people who seem to have blinders on, unable to see the obvious -- but merely operating under a different framework.
There are, of course, some differences between the frameworks that scientists propose (and regularly discard in favor of better ones) and those religious and political frameworks that somehow achieve a do-not-violate sanctity (John Calvin used to enforce his notion of sanctity during the Protestant Reformation by burning heretics at the stake; political police tend to be equally sure of themselves). The astronomer Carl Sagan observed:In science it often happens that scientists say, "You know that's a really good argument, my position is mistaken," and then they actually change their minds and you never hear that old view from them again.... I cannot recall the last time something like that has happened in politics or religion. It's very rare that a senator, say, replies, "That's a good argument. I will now change my political affiliation."
Frameworks do save us from having to evaluate everything from scratch, but they have their hazards, as Nietzsche noted: "Convictions are more dangerous enemies of truth than lies."Nothing causes as much destruction, misery, and death as obsession with a truth believed absolute. Every crime in history is the product of some fanaticism. Every massacre is performed in the name of virtue; in the name of legitimate nationalism, a true religion, a just ideology, the fight against Satan.the French molecular biologist François Jacob, 1988
The characteristic of all fundamentalism is that it has found absolute certainty -- the certainty of class warfare, the certainty of science, or the literal certainty of the Bible -- a certainty of the person who has finally found a solid rock to stand upon which, unlike other rocks, is "solid all the way down." Fundamentalism, however, is a terminal form of human consciousness in which development is stopped, eliminating the uncertainty and risk that real growth entails.the American physicist Heinz Pagels, 1988
IN ADDITION to the seductive attractions of deductive frameworks, it has not been obvious what the alternative is -- and it's often better to go with a framework that frequently works than none at all. Furthermore, the proponents of deductive frameworks usually appear formidably hardheaded and "rational," in contrast to the people groping around for a better framework; simplistic deduce-from-the-premises frameworks readily attract followers, readily infect other agendas (perhaps accounting for some of the overlap in U.S. supporters of religious fundamentalism and judicial "strict constructionism" -- and the considerably higher percentages of physical scientists found in those camps than biological scientists).
Yet even physics eventually had to give up determinism, accept quantum mechanics, and start using fuzzy sets. And most of life, outside of photosynthesis and metabolism and the other chemical engineering wonders of our bodily organs, is not routine. There is no true "balance of nature," because ecosystems and species are always evolving. Inconsistency is sometimes the name of the game. Animals that stick to a behavioral routine get eaten by an opportunistic predator that can predict the evening visits to the waterhole, etc.; our Homo erectus ancestors made a good living by lobbing discus-shaped rocks into the midst of a tightly packed herd lapping up the lake at sunset.
Inconsistency is part of flexibility, of nature's strategy of keeping options open. Animals that cannot adapt to new environments will not survive the incessant fluctuations of climate. Judicial systems that cannot grow and change with our society's evolving problems will become rigid anachronisms that promote social earthquakes. Consistency and rationality are human virtues in dealing with certain potentially orderly situations; we make excellent use of them in engineering and legal systems, but we shouldn't expect living systems to have made them centerpieces of their operation in a changing, unpredictable world.
AND I'LL BET SOMEONE THOUGHT that "Noise" was an unappreciative name for me to give my pet cat, rather like calling her "Pest" -- but given how creative that noise is, it is more like having a playful pair of cats named "Selection" and "Noise," named for the two flip sides of the darwinian evolutionary process. Having only one cat, I suppose that I should give her the one name that combines both concepts: "Darwin."
Technology treats noise as an unwanted impediment, darwinism as a means of exploring new avenues. But here we see it as a stimulus to evolve redundant machinery -- whose secondary uses may be revolutionary. There may even have been a "noise window" in hominid evolution: Lacking sufficient neuron noise to overcome, ice-age hominids might have become proficient projectile predators without the extra serial buffers for the massively serial scheme. While timing precision is the argument for why so many parallel-planning tracks were evolved in the first place, the really interesting things are the possible spare-time uses -- if those extra buffers are capable of randomly sequencing other things when not needed for throwing-hammering-clubbing muscle commands.
If the separate tracks can also be unhitched to operate independently, then by providing many candidate queues, it might foster stringing words together into more sophisticated sentences, or schemas into more credible scenarios. Rather than our productive language and planning-for-the-future consciousness arising gradually through their own selective advantages, they could have emerged as novel spare-time uses of neural machinery originally under selection for more mundane forelimb movements.
Neurallike networks, once they become capable of generating randomly varied sequences, then successive selections by remembered environments, do offer an obvious route to machine intelligence and intelligent robots -- though, should we succeed, we shall surely have to cope with machine imagination and machine "free will." We do not yet know how much of our own mental life might be explained by serendipitous secondary benefits of stochastic sequencers, and their tendency to partition the sequencer population into subpopulations where the minorities get to continue evolving on their own. And occasionally capture consciousness, when achieving a high ranking.
But just as darwinian gradualism has been supplemented with notions of sexual and group selection, isolation of subpopulations and allopatric speciation, stasis and "fast tracks," so we might expect a fuller understanding of our mental life to identify additional processes that regulate and elaborate the stochastic shaping-up of novel constructs. "Higher consciousness" is a much overused phrase, but we shall need some such concept to designate the "virtual machines" that can be constructed using stochastic sequencers as a basis.What Ulysses preserves from the lotus, from Circe's drugs and the Siren's song, is not merely the past or the future. Memory really matters -- for individuals, for the collectivity, for civilization -- only if it binds together the imprint of the past and the project of the future, if it enables us to act without forgetting what we wanted to do, to become without ceasing to be, and to be without ceasing to become.the Italian writer Italo Calvino, 1975
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The Cerebral Symphony (Bantam 1989) is my book on animal and human consciousness, using the setting of the Marine Biological Labs and Cape Cod. AVAILABILITY is limited.