The Mind’s I: Fantasies and Reflections on Self and Soul

9 Allen Wheelis Spirit[12]

We come into being as a slight thickening at the end of a long thread. Cells proliferate, become an excrescence, assume the shape of a man. The end of the thread now lies buried within, shielded, inviolate. Our task is to bear it forward, pass it on. We flourish for a moment, achieve a bit of singing and dancing, a few memories we would carve in stone, then we wither, twist out of shape. The end of the thread lies now in our children, extends back through us, unbroken, unfathomably into the past. Numberless thickenings have appeared on it, have flourished and have fallen away as we now fall away. Nothing remains but the germ-line. What changes to produce new structures as life evolves is not the momentary excrescence but the hereditary arrangements within the thread.

We are carriers of spirit. We know not how nor why nor where. On our shoulders, in our eyes, in anguished hands through unclear realm, into a future unknown, unknowable, and in continual creation, we bear its full weight. Depends it on us utterly, yet we know it not. We inch it forward with each beat of heart, give to it the work of hand, of mind. We falter, pass it on to our children, lay out our bones, fall away, are lost, forgotten. Spirit passes on, enlarged, enriched, more strange, complex.

We are being used. Should we not know in whose service? To whom, to what, give we unwitting loyalty? What is this quest? Beyond that which we have what could we want? What is a spirit?

A river or a rock, writes Jacques Monod, “we know, or believe, to have been molded by the free play of physical forces to which we cannot attribute any design, any ‘project’ or purpose. Not, that is, if we accept the basic premise of the scientific method, to wit, that nature is objective and not projective.”

The basic premise carries a powerful appeal. For we remember a time, no more than a few generations ago, when the opposite seemed manifest, when the rock wanted to fall, the river to sing or fto rage. Willful spirits roamed the universe, used nature with whim. And we know what gains in understanding and control have come to us from the adoption of a point of view which holds that natural objects and events are without goal or intention. The rock doesn’t want anything, the volcano pursues no purpose, rivers quests not the sea, wind seeks no destination.

But thee is another view. The animism of the primitive is not the only alternative to scientific objectivity. This objectivity may be valid for the time spans in which we are accustomed to reckon, yet untrue for spans of enormously greater duration. The proposition that light travels in a straight line, unaffected by adjacent masses, serves us well in surveying our farm, yet makes for error in the mapping of distant galaxies. Likewise, the proposition that nature, what is just “out there,” is without purpose, severs us well as we deal with nature in days or years or lifetimes, yet may mislead us on the plains of eternity.

Spirit rises, matter falls. Spirit reaches like aflame, a leap of dancer. Out of the void it creates form like a god, is god. Spirit was from the start, though even that beginning may have been an ending of some earlier start. If we look back far enough we arrive at a primal mist wherein spirit is but a restlessness of atoms, a trembling of something there that will not stay in stillness and in cold.

Matter would have the universe a uniform dispersion, motionless, complete. Spirit would have an earth, a heaven and a hell, whirl and conflict, an incandescent sun to drive away the dark, to illuminate good and evil, would have thought, memory, desire, would build a stairway of forms increasing in complexity, inclusiveness, to a heaven ever receding above, changing always in configuration, becoming when reached but the way to more distant heavens, the last… but there is no last, for spirit tends upward without end, wanders, spirals, dips, but tends ever upward, ruthlessly using lower forms to create higher forms, moving toward ever greater inwardness, consciousness, spontaneity, to an ever greater freedom.

Particles become animate. Spirit leaps aside from matter, which tugs forever to pull it down, to make it still. Minute creatures writhe in warm oceans. Ever more complex become the tiny forms which bear for a moment a questing spirit. They come together, touch, spirit is beginning to create love. They touch, something passes. They die, die, die, endlessly. Who shall know the spawnings in the rivers of our past? Who shall count the waltzing grunion of that surf? Who will mourn the rabbits of the plains, the furry tides of lemmings? They die, die, die, but have touched, and something passes. Spirit leaps forever away, creates new bodies, endlessly, ever more complex vessels to bear spirit forward, pass it on enlarged to those who follow.

Virus becomes bacteria, becomes algae, becomes fern. Thrust of spirit cracks stone, drives up the Douglas fir. Amoeba reaches out soft blunt arms in ceaseless motion to find the world, to know it better, to bring it in, growing larger, questing further, ever more capacious of spirit. Anemone becomes squid, becomes fish, wriggling becomes swimming, becomes crawling: fish becomes slug, becomes lizard, crawling becomes walking, becomes running, becomes flying. Living things reach out to each other, spirit leaps between. Tropism becomes scent, becomes fascination, becomes lust, becomes love. Lizard to fox to monkey to man, in a look, in a word, we come together, touch, die, serve spirit without knowing, carry it forward, pass it on. Ever more winged this spirit, ever greater its leaps. We love someone far away, someone who died a long time ago.

“Man is the vessel of the Spirit,” writes Erich Heller; “…Spirit is the voyager who, passing through the land of man, bids the human soul to follow it to the Spirit’s purely spiritual destination.”

Viewed closely, the path of spirit is seen to meander, is a glisten of snail’s way in night forest, but from a height minor turnings merge into steadiness of course. Man has reached a ledge from which to look back. For thousands of years the view is clear, and beyond, through a haze, for thousands more, we still see quite a bit. The horizon is millions of years behind us. Beyond the vagrant turnings of our last march stretches a shining path across that vast expanse running straight. Man did not begin it nor will he end it, but makes it now, finds the passes, cuts the channels. Whose way is it we so further? Not man’s; for there’s our first footprint. Not life’s; for there’s still the path when life was not yet.

Spirit is the traveler, passes now through the realm of man. We did not create spirit, do not possess it, cannot define it, are but the bearers. We take it from unmourned and forgotten forms, carry it through our span, will pass it on, enlarged or diminished, to those who follow. Spirit is the voyager, man is the vessel.

Spirit creates and spirit destroys. Creation without destruction is not possible, destruction without creation feeds on past creation, reduces form to matter, tends toward stillness. Spirit creates more than it destroys (though not in every season, nor even every age, hence those meanderings, those turnings back, wherein the longing of matter for stillness triumphs in destruction) and this preponderance of creation makes for the overall steadiness of course.

From primal mist of matter to spiraled galaxies and clockwork solar systems, from molten rock to an earth of air and land and water, from heaviness to lightness to life, sensation to perception, memory to consciousness—man now holds a mirror, spirit sees itself. Within the river currents turn back, eddies whirl. The river itself falters, disappears, emerges, moves on. The general course is the growth of form, increasing awareness, matter to mind consciousness. The harmony of man and nature is to be found in continuing this journey along its ancient course toward greater freedom and awareness.

Reflections

In these poetic passages, psychiatrist Allen Wheelis portrays the eerie disorienting view that modern science has given us of our place in the scheme of things. Many scientists, not to mention humanists, find this a very difficult view to swallow and look for some kind of spiritual essence, perhaps intangible, that would distinguish living beings, particularly humans, from the inanimate rest of the universe. How does anima come from atoms?

Wheelis’s concept of “spirit” is not that sort of essence. It is a way of describing the seemingly purposeful path of evolution as if there were one guiding force behind it. If there is, it is that which Richard Dawkins in the powerful selection that follows so clearly states: survival of stable replicators. In his preface Dawkins candidly writes: “We are survival machines—robot vehicles blindly programmed to preserve the selfish molecules known to us as genes. This is a truth which still fills me with astonishment. Though I have known it for years, I never seem to get fully used to it. One of my hopes is that I may have some success in astonishing others.”

D.R.H.

10 Richard Dawkins Selfish Genes And Selfish Memes[13]

In the beginning was simplicity. It is difficult enough explaining how even a simple universe began. I take it as agreed that it would be even harder to explain the sudden springing up, fully armed, of complex order-life, or a being capable of creating life. Darwin’s theory of evolution by natural selection is satisfying because it shows us a way in which simplicity could change into complexity, how unordered atoms could group themselves into ever more complex patterns until they ended up manufacturing people. Darwin provides a solution, the only feasible one so far suggested, to the deep problem of our existence. I will try to explain the great theory in a more general way than is customary, beginning with the time before evolution itself began.

Darwin’s ‘survival of the fittest’ is really a special case of a more general law of survival of the stable. The universe is populated by stable things. A stable thing is a collection of atoms which is permanent enough or common enough to deserve a name. It may be a unique collection of atoms, such as the Matterhorn, which lasts long enough to be worth naming. Or it may be a class of entities, such as rain drops, which come into existence at a sufficiently high rate to deserve a collective name, even if any one of them is short-lived. The things which we see around us, and which we think of as needing explanation—rocks, galaxies, ocean waves—are all, to a greater or lesser extent, stable patterns of atoms. Soap bubbles tend to be spherical because this is a stable configuration for thin films filled with gas. In a spacecraft, water is also stable in spherical globules, but on earth, where there is gravity, the stable surface for standing water is flat and horizontal. Salt crystals tend to be cubes because this is a stable way of packing sodium and chloride ions together. In the sun the simplest atoms of all, hydrogen atoms, are fusing to form helium atoms, because in the conditions which prevail there the helium configuration is more stable. Other even more complex atoms are being formed in stars all over the universe, and were formed in the “big bang” which, according to the prevailing theory, initiated the universe. This is originally where the elements on our world came from.

Sometimes when atoms meet they link up together in chemical reaction to form molecules, which may be more or less stable. Such molecules can be very large. A crystal such as a diamond can be regarded as a single molecule, a proverbially stable one in this case, but also a very simple one since its internal atomic structure is endlessly repeated. In modern living organisms there are other large molecules which are highly complex, and their complexity shows itself on several levels. The hemoglobin of our blood is a typical protein molecule. It is built up from chains of smaller molecules, amino acids, each containing a few dozen atoms arranged in a precise pattern. In the hemoglobin molecule there are 574 amino acid molecules. These are arranged in four chains, which twist around each other to form a globular three-dimensional structure of bewildering complexity. A model of a hemoglobin molecule looks rather like a dense thornbush. But unlike a real thornbush it is not a haphazard approximate pattern but a definite invariant structure, identically repeated, with not a twig nor a twist out of place, over six thousand million million million times in an average human body. The precise thornbush shape of a protein molecule such as hemoglobin is stable in the sense that two chains consisting of the same sequences of amino acids will tend, like two springs, to come to rest in exactly the same three-dimensional coiled pattern. Hemoglobin thornbushes are springing into their “preferred” shape in your body at a rate of about four hundred million million per second, and others are being destroyed at the same rate.

Hemoglobin is a modern molecule, used to illustrate the principle that atoms tend to fall into stable patterns. The point that is relevant here is that, before the coming of life on earth, some rudimentary evolution of molecules could have occurred by ordinary processes of physics and chemistry. There is no need to think of design or purpose or directedness. If a group of atoms in the presence of energy falls into a stable pattern it will tend to stay that way. The earliest form of natural selection was simply a selection of stable forms and a rejection of unstable ones. There is no mystery about this. It had to happen by definition.

From this, of course, it does not follow that you can explain the existence of entities as complex as man by exactly the same principles on their own. It is no good taking the right number of atoms and shaking them together with some external energy till they happen to fall into the right pattern, and out drops Adam! You may make a molecule consisting of a few dozen atoms like that, but a man consists of over a thousand million million million million atoms. To try to make a man, you would have to work at your biochemical cocktail-shaker for a period so long that the entire age of the universe would seem like an eye-blink, and even then you would not succeed. This is where Darwin’s theory, in its most general form, comes to the rescue. Darwin’s theory takes over from where the story of the slow building up of molecules leaves off.

The account of the origin of life which I shall give is necessarily speculative; by definition, nobody was around to see what happened. There are a number of rival theories, but they all have certain features in common. The simplified account I shall give is probably not too far from the truth.

We do not know what chemical raw materials were abundant on earth before the coming of life, but among the plausible possibilities are water, carbon dioxide, methane, and ammonia: all simple compounds known to be present on at least some of the other planets in our solar system. Chemists have tried to imitate the chemical conditions of the young earth. They have put these simple substances in a flask and supplied a source of energy such as ultraviolet light or electric sparks—artificial simulation of primordial lightning. After a few weeks of this, something interesting is usually found inside the flask: a weak brown soup containing a large number of molecules more complex than the ones originally put in. In particular, amino acids have been found—the building blocks of proteins, one of the two great classes of biological molecules. Before these experiments were done, naturally occurring amino acids would have been thought of as diagnostic of the presence of life. If they had been detected on, say, Mars, life on that planet would have seemed a near certainty. Now, however, their existence need imply only the presence of a few simple gases in the atmosphere and some volcanoes, sunlight, or thundery weather. More recently, laboratory simulations of the chemical conditions of earth before the coming of life have yielded organic substances called purines and pyrimidines. These are building blocks of the genetic molecule, DNA itself.

Processes analogous to these must have given rise to the “primeval soup” which biologists and chemists believe constituted the seas some three to four thousand million years ago. The organic substances became locally concentrated, perhaps in drying scum round the shores, or in tiny suspended droplets. Under the further influence of energy such as ultraviolet light from the sun, they combined into larger molecules. Nowadays large organic molecules would not last long enough to be noticed: they would be quickly absorbed and broken down by bacteria or other living creatures. But bacteria and the rest of us are late-comers, and in those days large organic molecules could drift unmolested through the thickening broth.

At some point a particularly remarkable molecule was formed by accident. We will call it the Replicator. It may not necessarily have been the biggest or the most complex molecule around, but it had the extraordinary property of being able to create copies of itself. This may seem a very unlikely sort of accident to happen. So it was. It was exceedingly improbable. In the lifetime of a man, things which are that improbable can be treated for practical purposes as impossible. That is why you will never win a big prize on the football pools. But in our human estimates of what is probable and what is not, we are not used to dealing in hundreds of millions of years. If you filled in pools coupons every week for a hundred million years you would very likely win several jackpots.

Actually a molecule which makes copies of itself is not as difficult to imagine as it seems at first, and it only had to arise once. Think of the replicator as a mold or template. Imagine it as a large molecule consisting of a complex chain of various sorts of building block molecules. The small building blocks were abundantly available in the soup surrounding the replicator. Now suppose that each building block has an affinity for its own kind. Then whenever a building block from out in the soup lands up next to a part of the replicator for which it has an affinity, it will tend to stick there. The building blocks which attach themselves in this way will automatically be arranged in a sequence which mimics that of the replicator itself. It is easy then to think of them joining up to form a stable chain just as in the formation of the original replicator. This process could continue as a progressive stacking up, layer upon layer. This is how crystals are formed. On the other hand, the two chains might split apart, in which case we have two replicators, each of which can go on to make further copies.

A more complex possibility is that each building block has affinity not for its own kind, but reciprocally for one particular other kind. Then the replicator would act as a template not for an identical copy, but for a kind of “negative,” which would in its turn remake an exact copy of the original positive. For our purposes it does not matter whether the original replication process was positive-negative or positive-positive, though it is worth remarking that the modern equivalents of the first replicator, the DNA molecules, use positive-negative replication. What does matter is that suddenly a new kind of “stability” came into the world. Previously it is probable that no particular kind of complex molecule was very abundant in the soup, because each was dependent on building blocks happening to fall by luck into a particular stable configuration. As soon as the replicator was born it must have spread its copies rapidly throughout the seas, until the smaller building block molecules became a scarce resource, and other larger molecules were formed more and more rarely.

So we seem to arrive at a large population of identical replicas. But now we must mention an important property of any copying process: it is not perfect. Mistakes will happen. I hope there are no misprints in this book, but if you look carefully you may find one or two. They will probably not seriously distort the meaning of the sentences, because they will be “first-generation” errors. But imagine the days before printing, when books such as the Gospels were copied by hand. All scribes, however careful, are bound to make a few errors, and some are not above a little willful “improvement.” If they all copied from a single master original, meaning would not be greatly perverted. But let copies be made from other copies, which in their turn were made from other copies, and errors will start to become cumulative and serious. We tend to regard erratic copying as a bad thing, and in the case of human documents it is hard to think of examples where errors can be described as improvements. I suppose the scholars of the Septuagint could at least be said to have started something big when they mistranslated the Hebrew word for “young woman” into the Greek word for “virgin,” coming up with the prophecy: “Behold a virgin shall conceive and bear a son....” Anyway, as we shall see, erratic copying in biological replicators can in a real sense give rise to improvement, and it was essential for the progressive evolution of life that some errors were made. We do not know how accurately the original replicator molecules made their copies. Their modern descendants, the DNA molecules, are astonishingly faithful compared with the most high-fidelity human copying process, but even they occasionally make mistakes, and it is ultimately these mistakes which make evolution possible. Probably the original replicators were far more erratic, but in any case we may be sure that mistakes were made, and these mistakes were cumulative.

As mis-copyings were made and propagated, the primeval soup became filled by a population not of identical replicas, but of several varieties of replicating molecules, all “descended” from the same ancestor. Would some varieties have been more numerous than others? Almost certainly yes. Sonic varieties would have been inherently more stable than others. Certain molecules, once formed, would be less likely than others to break tip again. These types would become relatively numerous in the soup, not only as a direct logical consequence of their “longevity,” but also because they would have a long time available for making copies of themselves. Replicators of high longevity would therefore tend to become more numerous and, other things being equal, there would have been an “evolutionary trend” toward greater longevity in the population of molecules.

But other things were probably not equal, and another property of a replicator variety which must have had even more importance in spreading it through the population was speed of replication, or “fecundity.” If replicator molecules of type A make copies of themselves on average once a week while those of type B make copies of themselves once an hour, it is not difficult to see that pretty soon type A molecules are going to be far outnumbered, even if they “live” much longer than B molecules. There would therefore probably have been an “evolutionary trend” towards higher “fecundity” of molecules in the soup. A third characteristic of replicator molecules which would have been positively selected is accuracy of replication. If molecules of type X and type Y last the same length of time and replicate at the same rate, but X makes a mistake on average every tenth replication while Y makes a mistake only every hundredth replication, Y will obviously become more numerous. The X contingent in the population loses not only the errant “children” themselves, but also all their descendants, actual or potential.

If you already know something about evolution, you may find something slightly paradoxical about the last point. Can we reconcile the idea that copying errors are an essential prerequisite for evolution to occur, with the statement that natural selection favors high copying-fidelity? The answer is that although evolution may seem, in some vague sense, a “good thing,” especially since we are the product of it, nothing actually “wants” to evolve. Evolution is something that happens, willy-nilly, in spite of all the efforts of the replicators (and nowadays of the genes) to prevent it happening. Jacques Monod made this point very well in his Herbert Spencer lecture, after wryly remarking: “Another curious aspect of the theory of evolution is that everybody thinks he understands it!”

To return to the primeval soup, it must have become populated by stable varieties of molecule: stable in that either the individual molecules lasted a long time, or they replicated rapidly, or they replicated accurately. Evolutionary trends toward these three kinds of stability took place in the following sense: If you had sampled the soup at two different times, the later sample would have contained a higher proportion of varieties with high longevity/fecundity/copying-fidelity. This is essentially what a biologist means by evolution when he is speaking of living creatures, and the mechanism is the same-natural selection.

Should we then call the original replicator molecules “living”? Who cares? I might say to you “Darwin was the greatest man who has ever lived,” and you might say, “No, Newton was,” but I hope we would not prolong the argument. The point is that no conclusion of substance would be affected whichever way our argument was resolved. The facts of the lives and achievements of Newton and Darwin remain totally unchanged whether we label them “great” or not. Similarly, the story of the replicator molecules probably happened something like the way I am telling it, regardless of whether we choose to call them “living.” Human suffering has been caused because too many of us cannot grasp that words are only tools for our use, and that the mere presence in the dictionary of a word like “living” does not mean it necessarily has to refer to something definite in the real world. Whether we call the early replicators living or not, they were the ancestors of life; they were our founding fathers.

The next important link in the argument, one which Darwin himself laid stress on (although he was talking about animals and plants, not molecules) is competition. The primeval soup was not capable of supporting an infinite number of replicator molecules. For one thing, the earth’s size is finite, but other limiting factors must also have been important. In our picture of the replicator acting as a template or mold, we supposed it to be bathed in a soup rich in the small building block molecules necessary to make copies. But when the replicators became numerous, building blocks must have been used up at such a rate that they became a scarce and precious resource. Different varieties or strains of replicator must have competed for them. We have considered the factors which would have increased the numbers of favored kinds of replicator. We can now see that less-favored varieties must actually have become less numerous because of competition, and ultimately many of their lines must have gone extinct. There was a struggle for existence among replicator varieties. They did not know they were struggling, or worry about it; the struggle was conducted without any hard feelings, indeed without feelings of any kind. But they were struggling, in the sense that any miscopying which resulted in a new higher level of stability, or a new way of reducing the stability of rivals, was automatically preserved and multiplied. The process of improvement was cumulative. Ways of increasing stability and of decreasing rivals’ stability became more elaborate and more efficient. Some of them may even have “discovered” how to break up molecules of rival varieties chemically, and to use the building blocks so released for making their own copies. These proto-carnivores simultaneously obtained food and removed competing rivals. Other replicators perhaps discovered how to protect themselves, either chemically or by building a physical wall of protein around themselves. This may have been how the first living cells appeared. Replicators began not merely to exist, but to construct for themselves containers, vehicles for their continued existence. The replicators which survived were the ones which built survival machines for themselves to live in. The first survival machines probably consisted of nothing more than a protective coat. But making a living got steadily harder as new rivals arose with better and more effective survival machines. Survival machines got bigger and more elaborate, and the process was cumulative and progressive.

Was there to be any end to the gradual improvement in the techniques and artifices used by the replicators to ensure their own continuance in the world? There would be plenty of time for improvement. What weird engines of self-preservation would the millennia bring forth? Four thousand million years on, what was to be the fate of the ancient replicators? They did not die out, for they are past masters of the survival arts. But do not look for them floating loose in the sea; they gave up that cavalier freedom long ago. Now they swarm in huge colonies, safe inside gigantic lumbering robots, sealed off from the outside world, communicating with it by tortuous indirect routes, manipulating it by remote control. They are in you and in me; they created us, body and mind; and their preservation is the ultimate rationale for our existence. They have come a long way, those replicators. Now they go by the name of genes, and we are their survival machines.

Once upon a time, natural selection consisted of the differential survival of replicators floating free in the primeval soup. Now natural selection favors replicators which are good at building survival machines, genes which are skilled in the art of controlling embryonic development. In this, the replicators are no more conscious or purposeful than they ever were. The same old processes of automatic selection between rival molecules by reason of their longevity, fecundity, and copying-fidelity, still go on as blindly and as inevitably as they did in the far-off days. Genes have no foresight. They do not plan ahead. Genes just are, some genes more so than others, and that is all there is to it. But the qualities which determine a gene’s longevity and fecundity are not so simple as they were. Not by a long way.

In recent years—the last six hundred million or so—the replicators have achieved notable triumphs of survival-machine technology such as the muscle, the heart, and the eye (evolved several times independently). Before that, they radically altered fundamental features of their way of life as replicators, which must be understood if we are to proceed with the argument.

The first thing to grasp about a modern replicator is that it is highly gregarious. A survival machine is a vehicle containing not just one gene but many thousands. The manufacture of a body is a cooperative venture of such intricacy that it is almost impossible to disentangle the contribution of one gene from that of another. A given gene will have many different effects on quite different parts of the body. A given part of the body will be influenced by many genes, and the effect of any one gene depends on interaction with many others. Some genes act as master genes controlling the operation of a cluster of other genes. In terms of the analogy, any given page of the plans makes reference to many different parts of the building; and each page makes sense only in terms of cross-references to numerous other pages.

This intricate interdependence of genes may make you wonder why we use the word “gene” at all. Why not use a collective noun like “gene complex”? The answer is that for many purposes that is indeed quite a good idea. But if we look at things in another way, it does make sense too to think of the gene complex as being divided up into discrete replicators or genes. This arises because of the phenomenon of sex. Sexual reproduction has the effect of mixing and shuffling genes. This means that any one individual body is just a temporary vehicle for a short-lived combination of genes. The combination of genes that is any one individual may be short-lived, but the genes themselves are potentially very long-lived. Their paths constantly cross and recross down the generations. One gene may be regarded as a unit which survives through a large number of successive individual bodies.

Natural selection in its most general form means the differential survival of entities. Some entities live and others die but, in order for this selective death to have any impact on the world, an additional condition must be met. Each entity must exist in the form of lots of copies, and at least some of the entities must be potentially capable of surviving—in the form of popies—for a significant period of evolutionary time. Small genetic units have these properties; individuals, groups, and species do not. It was the great achievement of Gregor Mendel to show that hereditary units can be treated in practice as indivisible and independent particles. Nowadays we know that this is a little too simple. Even a cistron is occasionally divisible and any two genes on the same chromosome are not wholly independent. What I have done is to define a gene as a unit which, to a high degree, approaches the ideal of indivisible particulateness. A gene is not indivisible, but it is seldom divided. It is either definitely present or definitely absent in the body of any given individual. A gene travels intact from grandparent to grandchild, passing straight through the intermediate generation without being merged with other genes. If genes continually blended with each other, natural selection as we now understand it would be impossible. Incidentally, this was proved in Darwin’s lifetime, and it caused Darwin great worry since in those days it was assumed that heredity was a blending process. Mendel’s discovery had already been published, and it could have rescued Darwin, but alas he never knew about it: nobody seems to have read it until years after Darwin and Mendel had both died. Mendel perhaps did not realize the significance of his findings, otherwise he might have written to Darwin.

Another aspect of the particulateness of the gene is that it does not grow senile; it is no more likely to die when it is a million years old than when it is only a hundred. It leaps from body to body down the generations, manipulating body after body in its own way and for its own ends, abandoning a succession of mortal bodies before they sink in senility and death.

The genes are the immortals, or rather, they are defined as genetic entities which come close to deserving the title. We, the individual survival machines in the world, can expect to live a few more decades. But the genes in the world have an expectation of life which must be measured not in decades but in thousands and millions of years.

Survival machines began as passive receptacles for the genes, providing little more than walls to protect them from the chemical warfare of their rivals and the ravages of accidental molecular bombardment. In the early days they “fed” on organic molecules freely available in the soup. This easy life came to an end when the organic food in the soup, which had been slowly built up under the energetic influence of centuries of sunlight, was all used up. A major branch of survival machines, now called plants, started to use sunlight directly themselves to build up complex molecules from simple ones, reenacting at much higher speed the synthetic processes of the original soup. Another branch, now known as animals, “discovered” how to exploit the chemical labors of the plants, either by eating them, or by eating other animals. Both main branches of survival machines evolved more and more ingenious tricks to increase their efficiency in their various ways of life, and new ways of life were continually being opened up. Subbranches and sub-subbranches evolved, each one excelling in a particular specialized way of making a living: in the sea, on the ground, in the air, underground, up trees, inside other living bodies. This subbranching has given rise to the immense diversity of animals and plants which so impresses us today.

Both animals and plants evolved into many-celled bodies, complete copies of all the genes being distributed to every cell. We do not know when, why, or how many times independently, this happened. Some people use the metaphor of a colony, describing a body as a colony of cells. I prefer to think of the body as a colony of genes, and of the cell as a convenient working unit for the chemical industries of the genes.

Colonies of genes they may be but, in their behavior, bodies have undeniably acquired an individuality of their own. An animal moves as a coordinated whole, as a unit. Subjectively I feel like a unit, not a colony. This is to be expected. Selection has favored genes which cooperate with others. In the fierce competition for scarce resources, in the relentless struggle to eat other survival machines, and to avoid being eaten, there must have been a premium on central coordination rather than anarchy within the communal body. Nowadays the intricate mutual coevolution of genes has proceeded to such an extent that the communal nature of an individual survival machine is virtually unrecognizable. Indeed many biologists do not recognize it, and will disagree with me.

One of the most striking properties of survival-machine behavior is its apparent purposiveness. By this I do not just mean that it seems to be well calculated to help the animal’s genes to survive, although of course it is. I am talking about a closer analogy to human purposeful behavior. When we watch an animal “searching” for food, or for a mate, or for a lost child, we can hardly help imputing to it some of the subjective feelings we ourselves experience when we search. These may include “desire” for some object, a “mental picture” of the desired object, an “aim” or “end in view.” Each one of us knows, from the evidence of his own introspection, that, at least in one modern survival machine, this purposiveness has evolved the property we call “consciousness.” I am not philosopher enough to discuss what this means, but fortunately it does not matter for our present purposes because it is easy to talk about machines which behave as if motivated by a purpose, and to leave open the question whether they actually are conscious. These machines are basically very simple, and the principles of unconscious purposive behavior are among the commonplaces of engineering science. The classic example is the Watt steam governor.

The fundamental principle involved is called negative feedback, of which there are various different forms. In general what happens is this. The “purpose machine,” the machine or thing that behaves as if it had a conscious purpose, is equipped with some kind of measuring device which measures the discrepancy between the current state of things and the “desired” state. It is built in such a way that the larger this discrepancy is, the harder the machine works. In this way the machine will automatically tend to reduce the discrepancy—this is why it is called negative feedback—and it may actually come to rest if the “desired” state is reached. The Watt governor consists of a pair of balls which are whirled round by a steam engine. Each ball is on the end of a hinged arm. The faster the balls fly round, the more does centrifugal force push the arms toward a horizontal position, this tendency being resisted by gravity. The arms are connected to the steam valve feeding the engine, in such a way that the steam tends to be shut off when the arms approach the horizontal position. So, if the engine goes too fast, some of its steam will be shut off, and it will tend to slow down. If it slows down too much, more steam will automatically be fed to it by the valve, and it will speed up again. Such purpose machines often oscillate due to overshooting and time-lags, and it is part of the engineer’s art to build in supplementary devices to reduce the oscillations.

The “desired” state of the Watt governor is a particular speed of rotation. Obviously it does not consciously desire it. The “goal” of a machine is simply defined as that state to which it tends to return. Modern purpose machines use extensions of basic principles like negative feedback to achieve much more complex “lifelike” behavior. Guided missiles, for example, appear to search actively for their target, and when they have it in range they seem to pursue it, taking account of its evasive twists and turns, and sometimes even “predicting” or “anticipating” them. The details of how this is done are not worth going into. They involve negative feedback of various kinds, “feed-forward,” and other principles well understood by engineers and now known to be extensively involved in the working of living bodies. Nothing remotely approaching consciousness needs to be postulated, even though a layman, watching its apparently deliberate and purposeful behavior, finds it hard to believe that the missile is not under the direct control of a human pilot.

It is a common misconception that because a machine such as a guided missile was originally designed and built by conscious man, then it must be truly under the immediate control of conscious man. Another variant of this fallacy is “computers do not really play chess, because they can only do what a human operator tells them.” It is important that we understand why this is fallacious, because it affects our understanding of the sense in which genes can be said to “control” behavior. Computer chess is quite a good example for making the point, so I will discuss it briefly.

Computers do not yet play chess as well as human grand masters, but they have reached the standard of a good amateur. More strictly, one should say programs have reached the standard of a good amateur, for a chess-playing program is not fussy which physical computer it uses to act out its skills. Now, what is the role of the human programmer? First, he is definitely not manipulating the computer from moment to moment, like a puppeteer pulling strings. That would be just cheating. He writes the program, puts it in the computer, and then the computer is on its own: there is no further human intervention, except for the opponent typing in his moves. Does the programmer perhaps anticipate all possible chess positions and provide the computer with a long list of good moves, one for each possible contingency? Most certainly not, because the number of possible positions in chess is so great that the world would come to an end before the list had been completed. For the same reason, the computer cannot possibly be programmed to try out “in its head” all possible moves, and all possible follow-ups, until it finds a winning strategy. There are more possible games of chess than there are atoms in the galaxy. So much for the trivial nonsolutions to the problem of programming a computer to play chess. It is in fact an exceedingly difficult problem, and it is hardly surprising that the best programs have still not achieved grand master status.

The programmer’s actual role is rather more like that of a father teaching his son to play chess. He tells the computer the basic moves of the game, not separately for every possible starting position, but in terms of more economically expressed rules. He does not literally say in plain English “bishops move in a diagonal,” but he does say something mathematically equivalent, such as, though more briefly: “New coordinates of bishop are obtained from old coordinates, by adding the same constant, though not necessarily with the same sign, to both old x coordinate and old y coordinate.” Then he might program in some “advice,” written in the same sort of mathematical or logical language, but amounting in human terms to hints such as “don’t leave your king unguarded,” or useful tricks such as “forking” with the knight. The details are intriguing, but they would take us too far afield. The important point is this: When it is actually playing, the computer is on its own and can expect no help from its master. All the programmer can do is to set the computer up beforehand in the best way possible, with a proper balance between lists of specific knowledge and hints about strategies and techniques.

The genes too control the behavior of their survival machines, not directly with their fingers on puppet strings, but indirectly like the computer programmer. All they can do is to set it up beforehand; then the survival machine is on its own, and the genes can only sit passively inside. Why are they so passive? Why don’t they grab the reins and take charge from moment to moment? The answer is that they cannot because of timelag problems. This is best shown by another analogy, taken from science fiction. A for Andromeda by Fred Hoyle and John Elliot is an exciting story, and, like all good science fiction, it has some interesting scientific points lying behind it. Strangely, the book seems to lack explicit mention of the most important of these underlying points. It is left to the reader’s imagination. I hope the authors will not mind if I spell it out here.

There is a civilization two hundred light years away, in the constellation of Andromeda.[14] They want to spread their culture to distant worlds. How best to do it? Direct travel is out of the question. The speed of light imposes a theoretical upper limit to the rate at which you can get from one place to another in the universe, and mechanical considerations impose a much lower limit in practice. Besides, there may not be all that mare worlds worth going to, and how do you know which direction to go in? Radio is a better way of communicating with the rest of the universe, since, if you have enough power to broadcast your signals in all directions rather than beam them in one direction, you can reach a very large number of worlds (the number increasing as the square of the distance the signal travels). Radio waves travel at the speed of light, which means the signal takes two hundred years to reach Earth from Andromeda. The trouble with this sort of distance is that you can never hold a conversation. Even if you discount the fact that each successive message from Earth would be transmitted by people separated from each other by twelve generations or so, it would be just plain wasteful to attempt to converse over such distances.

This problem will soon arise in earnest for us: it takes about four minutes for radio waves to travel between Earth and Mars. There can be no doubt that spacemen will have to get out of the habit of conversing in short alternating sentences, and will have to use long soliloquies or monologues, more like letters than conversations. As another example, Roger Payne has pointed out that the acoustics of the sea have certain peculiar properties, which mean that the exceedingly loud “song” of the humpback whale could theoretically be heard all the way round the world, provided the whales swim at a certain depth. It is not known whether they actually do communicate with each other over very great distances, but if they do they must be in much the same predicament as an astronaut on Mars. The speed of sound in water is such that it would take nearly two hours for the song to travel across the Atlantic Ocean and for a reply to return. I suggest this as an explanation for the fact that the whales deliver a continuous soliloquy, without repeating themselves, for a full eight minutes. They then go back to the beginning of the song and repeat it all over again, many times over, each complete cycle lasting about eight minutes.

The Andromedans of the story did the same thing. Since there was no point in waiting for a reply, they assembled everything they wanted to say into one huge unbroken message, and then they broadcast it out into space, over and over again, with a cycle time of several months. Their message was very different from that of the whales, however. It consisted of coded instructions for the building and programming of a giant computer. Of course the instructions were in no human language, but almost any code can be broken by a skilled cryptographer, especially if the designers of the code intended it to be easily broken. Picked up by the Jodrell Bank radio telescope, the message was eventually decoded, the computer built, and the program run. The results were nearly disastrous for mankind, for the intentions of the Andromedans were not universally altruistic, and the computer was well on the way to dictatorship over the world before the hero eventually finished it off with an axe.

From our point of view, the interesting question is in what sense the Andromedans could be said to be manipulating events on Earth. They had no direct control over what the computer did from moment to moment; indeed they had no possible way of even knowing the computer had been built, since the information would have taken two hundred years to get back to them. The decisions and actions of the computer were entirely its own. It could not even refer back to its masters for general policy instructions. All its instructions had to be built-in in advance, because of the inviolable two-hundred-year barrier. In principle, it must have been programmed very much like a chess-playing computer, but with greater flexibility and capacity for absorbing local information. This was because the program had to be designed to work not just on earth, but on any world possessing an advanced technology, any of a set of worlds whose detailed conditions the Andromedans had no way of knowing.

Just as the Andromedans had to have a computer on earth to take day-to-day decisions for them, our genes have to build a brain. But the genes are not only the Andromedans who sent the coded instructions; then are also the instructions themselves. The reason why they cannot manipulate our puppet strings directly is the same: time-lags. Genes work by controlling protein synthesis. This is a powerful way of manipulating the world, but it is slow. It takes months of patiently pulling protein strings to build an embryo. The whole point about behavior, on the other hand, is that it is fast. It works on a time scale not of months but of seconds and fractions of seconds. Something happens in the world, an owl flashes overhead, a rustle in the long grass betrays prey, and in milliseconds nervous systems crackle into action, muscles leap, and someone’s life is saved—or lost. Genes don’t have reaction times like that. Like the Andromedans, the genes can do only their best in advance by building a fast executive computer for themselves, and programming it in advance with rules and “advice” to cope with as many eventualities as they can “anticipate.” But life, like the game of chess, offers too many different possible eventualities for all of them to be anticipated. Like the chess programmer, the genes have to “instruct” their survival machines not in specifics, but in the general strategies and tricks of the living trade.

As J. Z. Young has pointed out, the genes have to perform a task analogous to prediction. When an embryo survival machine is being built, the dangers and problems of its life lie in the future. Who can say what carnivores crouch waiting for it behind what bushes, or what fleet-footed prey will dart and zigzag across its path? No human prophet, nor any gene. But some general predictions can be made. Polar bear genes can safely predict that the future of their unborn survival machine is going to be a cold one. They do not think of it as a prophecy, they do not think at all: they just build in a thick coat of hair, because that is what they have always done before in previous bodies, and that is why they still exist in the gene pool. They also predict that the ground is going to be snowy, and their prediction takes the form of making the coat of hair white and therefore camouflaged. If the climate of the Arctic changed so rapidly that the baby bear found itself born into a tropical desert, the predictions of the genes would be wrong, and they would pay the penalty. The young bear would die, and they inside it.

One of the most interesting methods of predicting the future is simulation. If a general wishes to know whether a particular military plan will be better than alternatives, he has a problem in prediction. There are unknown quantities in the weather, in the morale of his own troops, and in the possible countermeasures of the enemy. One way of discovering whether it is a good plan is to try it and see, but it is undesirable to use this test for all the tentative plans dreamed up, if only because the supply of young men prepared to die “for their country” is exhaustible and the supply of possible plans is very large. It is better to try the various plans out in dummy runs rather than in deadly earnest. This may take the form of full-scale exercises with “Northland” fighting “Southland” using blank ammunition, but even this is expensive in time and materials. Less wastefully, war games may be played, with tin soldiers and little toy tanks being shuffled around a large map.

Recently, computers have taken over large parts of the simulation function, not only in military strategy, but in all fields where prediction of the future is necessary, fields like economics, ecology, sociology, and many others. The technique works like this. A model of some aspect of the world is set up in the computer. This does not mean that if you unscrewed the lid you would see a little miniature dummy inside with the same shape as the object simulated. In the chess-playing computer there is no “mental picture” inside the memory banks recognizable as a chess board with knights and pawns sitting on it. The chess board and its current position would be represented by lists of electronically coded numbers. To us a map is a miniature scale model of a part of the world, compressed into two dimensions. In a computer, a map would more probably be represented as a list of towns and other spots, each with two numbers—its latitude and longitude. But it does not matter how the computer actually holds its model of the world in its head, provided that it holds it in a form in which it can operate on it, manipulate it, do experiments with it, and report back to the human operators in terms which they can understand. Through the technique of simulation, model battles can be won or lost, simulated airliners fly or crash, economic policies lead to prosperity or to ruin. In each case the whole process goes on inside the computer in a tiny fraction of the time it would take in real life. Of course there are good models of the world and bad ones, and even the good ones are only approximations. No amount of simulation can predict exactly what will happen in reality, but a good simulation is enormously preferable to blind trial and error. Simulation could be called vicarious trial and error, a term unfortunately preempted long ago by rat psychologists.

If simulation is such a good idea, we might expect that survival machines would have discovered it first. After all, they invented many of the other techniques of human engineering long before we came on the scene: the focusing lens and the parabolic reflector, frequency analysis of sound waves, servo-control, sonar, buffer storage of incoming information, and countless others with long names, whose details don’t matter. What about simulation? Well, when you yourself have a difficult decision to make involving unknown quantities in the future, you do go in for a form of simulation. You imagine what would happen if you did each of the alternatives open to you. You set up a model in your head, not of everything in the world, but of the restricted set of entities which you think may be relevant. You may see them vividly in your mind’s eye, or you may see and manipulate stylized abstractions of them. In either case it is unlikely that somewhere laid out in your brain is an actual spatial model of the events you are imagining. But, just as in the computer, the details of how your brain represents its model of the world are less important than the fact that it is able to use it to predict possible events. Survival machines which can simulate the future are one jump ahead of survival machines who can only learn on the basis of overt trial and error. The trouble with overt trial is that it takes time and energy. The trouble with overt error is that it is often fatal. Simulation is both safer and faster.

The evolution of the capacity to simulate seems to have culminated in subjective consciousness. Why this should have happened is, to me, the most profound mystery facing modern biology. There is no reason to suppose that electronic computers are conscious when they simulate, although we have to admit that in the future they may become so. Perhaps consciousness arises when the brain’s simulation of the world becomes so complete that it must include a model of itself. Obviously the limbs and body of a survival machine must constitute an important part of its simulated world; presumably for the same kind of reason, the simulation itself could be regarded as part of the world to be simulated. Another word for this might indeed be “self-awareness,” but I don’t find this a fully satisfying explanation of the evolution of consciousness, and this is only partly because it involves an infinite regress—if there is a model of the model, why not a model of the model of the model? …

Whatever the philosophical problems raised by consciousness, for the purpose of this story it can be thought of as the culmination of an evolutionary trend towards the emancipation of survival machines as executive decision-takers from their ultimate masters, the genes. Not only are brains in charge of the day-to-day running of survival-machine affairs, they have also acquired the ability to predict the future and act accordingly. They even have the power to rebel against the dictates of the genes, for instance in refusing to have as many children as they are able to. But in this respect man is a very special case, as we shall see.

What has all this to do with altruism and selfishness? I am trying to build up the idea that animal behavior, altruistic or selfish, is under the control of genes in only an indirect, but still very powerful, sense. By dictating the way survival machines and their nervous systems are built, genes exert ultimate power over behavior. But the moment-to-moment decisions about what to do next are taken by the nervous system. Genes are the primary policy-makers; brains are the executives. But as brains became more highly developed, they took over more and more of the actual policy decisions, using tricks like learning and simulation in doing so. The logical conclusion to this trend, not yet reached in any species, would be for the genes to give the survival machine a single overall policy instruction: do whatever you think best to keep us alive.

The laws of physics are supposed to be true all over the accessible universe. Are there any principles of biology which are likely to have similar universal validity? When astronauts voyage to distant planets and look for life, they can expect to find creatures too strange and unearthly for us to imagine. But is there anything which must be true of all life, wherever it is found, and whatever the basis of its chemistry? If forms of life exist whose chemistry is based on silicon rather than carbon, or ammonia rather than water, if creatures are discovered which boil to death at −100 degrees centigrade, if a form of life is found which is not based on chemistry at all but on electronic reverberating circuits, will there still be any general principle which is true of all life? Obviously I do not know but, if I had to bet, I would put my money on one fundamental principle. This is the law that all life evolves by the differential survival of replicating entities. The gene, the DNA molecule, happens to be the replicating entity which prevails on our own planet. There may be others. If there are, provided certain other conditions are met, they will almost inevitably tend to become the basis for an evolutionary process.

But do we have to go to distant worlds to find other kinds of replicator and other, consequent, kinds of evolution? I think that a new kind of replicator has recently emerged on this very planet. It is staring us in the face. It is still in its infancy, still drifting clumsily about in its primeval soup, but already it is achieving evolutionary change at a rate which leaves the old gene panting far behind.

The new soup is the soup of human culture. We need a name for the new replicator, a noun which conveys the idea of a unit of cultural transmission, or a unit of imitation. “Mimeme” comes from a suitable Greek root, but I want a monosyllable that sounds a bit like “gene.” I hope my classicist friends will forgive me if I abbreviate mimeme to meme. If it is any consolation, it could alternatively be thought of as being related to “memory,” or to the French word même. It should be pronounced to rhyme with “cream.”

Examples of memes are tunes, ideas, catch-phrases, clothes fashions, ways of making pots or of building arches. Just as genes propagate themselves in the gene pool by leaping from body to body via sperms or eggs, so memes propagate themselves in the meme pool by leaping from brain to brain via a process which, in the broad sense, can be called imitation. If a scientist hears, or reads about, a good idea, he passes it on to his colleagues and students. He mentions it in his articles and his lectures. If the idea catches on, it can be said to propagate itself, spreading from brain to brain. As my colleague N. K. Humphrey neatly summed up an earlier draft of this chapter: “… memes should be regarded as living structures, not just metaphorically but technically. When you plant a fertile meme in my mind, you literally parasitize my brain, turning it into a vehicle for the meme’s propagation in just the way that a virus may parasitize the genetic mechanism of a host cell. And this isn’t just a way of talking—the meme for, say, ‘belief in life after death’ is actually realized physically, millions of times over, as a structure in the nervous systems of individual men the world over.”

I conjecture that co-adapted meme-complexes evolve in the same kind of way as co-adapted gene-complexes. Selection favours memes which exploit their cultural environment to their own advantage. This cultural environment consists of other memes which are also being selected. The meme pool therefore comes to have the attributes of an evolutionarily stable set, which new memes find it hard to invade.

I have been a bit negative about memes, but they have their cheerful side as well. When we die there are two things we can leave behind us: genes and memes. We were built as gene machines, created to pass on our genes. But that aspect of us will be forgotten in three generations. Your child, even your grandchild, may bear a resemblance to you, perhaps in facial features, in a talent for music, in the colour of her hair. But as each generation passes, the contribution of your genes is halved. It does not take long to reach negligible proportions. Our genes may be immortal but the collection of genes which is any one of us is bound to crumble away. Elizabeth II is a direct descendant of William the Conqueror. Yet it is quite probable that she bears not a single one of the old king’s genes. We should not seek immortality in reproduction.

But if you contribute to the world’s culture, if you have a good idea, compose a tune, invent a spark plug, write a poem, it may live on, intact, long after your genes have dissolved in the common pool. Socrates may or may not have a gene or two alive in the world today, as G. C. Williams has remarked, but who cares? The meme-complexes of Socrates, Leonardo, Copernicus, and Marconi are still going strong.

Reflections

Dawkins is a master at expounding the reductionist thesis that says life and mind come out of a seething molecular tumult, when small units, accidentally formed, are subjected over and over to the merciless filter of fierce competition for resources with which to replicate. Reductionism sees all of the world as reducible to the laws of physics, with no room for so-called “emergent” properties or, to use an evocative though old-fashioned word, “entelechies”—higher-level structures that presumably cannot be explained by recourse to the laws that govern their parts.

Imagine this scenario: You send your nonfunctioning typewriter (or washing machine or photocopy machine) back to the factory for repair, and a month later they send it back reassembled correctly (as it had been when you sent it in), along with a note saying that they’re sorry—all the parts check out fine, but the whole simply doesn’t work. This would be considered outrageous. How can every part be perfect if the machine still doesn’t work right? Something has to be wrong somewhere! So common sense tells us, in the macroscopic domain of everyday life.

Does this principle continue to hold, however, as you go from a whole to its parts, then from those parts to their parts, and so on, level after level? Common sense would again say yes—and yet many people continue to believe such things as “You can’t derive the properties of water from the properties of hydrogen and oxygen atoms” or “A living being is greater than the sum of its parts.” Somehow people often envision atoms as simple billiard balls, perhaps with chemical valences but without much more detail. As it turns out, nothing could be further from the truth. When you get down to that very small size scale, the mathematics of “matter” becomes more intractable than ever. Consider this passage from Richard Mattuck’s text on interacting particles:

The quantum mechanics of an atom like oxygen, with its eight electrons, is far beyond our capability to completely solve analytically. A hydrogen or oxygen atom’s properties, not to mention those of a water molecule, are indescribably subtle, and are precisely the sources of water’s many elusive qualities. Many of those properties can be studied by computer simulations of many interacting molecules, using simplified models of the atoms. The better the model of the atom, the more realistic the simulation, naturally. In fact, computer models have become one of the most prevalent ways of discovering new properties of collections of many identical components, given knowledge only of the properties of an individual component. Computer simulations have yielded new insights into how galaxies form spiral arms, based on modeling a single star as a mobile gravitating point. Computer simulations have shown how solids, liquids, and gases vibrate, flow, and change state, based on modeling a single molecule as a simple electromagnetically interacting structure.

It is a fact that people habitually underestimate the intricacy and complexity that can result from a huge number of interacting units obeying formal rules at very high speeds, relative to our time scale.

Dawkins concludes his book by presenting his own meme about memes—software replicators that dwell in minds. He precedes his presentation of the notion by entertaining the idea of alternate life-support media. One that he fails to mention is the surface of a neutron star, where nuclear particles can band together and disband thousands of times faster than atoms do. In theory, a “chemistry” of nuclear particles could permit extremely tiny self-replicating structures whose high-speed lives would zoom by in an eyeblink, equally complex as their slow earthbound counterparts. Whether such life actually exists—or whether we could ever find out, assuming it did—is unclear, but it gives rise to the amazing idea of an entire civilization’s rise and fall in the period of a few earth days—a super-Lilliput! The selections by Stanislaw Lem in this book all share this quality; see especially selection 18, “The Seventh Sally.”

We bring this weird idea up to remind the reader to keep an open mind about the variability of media that can support complex lifelike or thoughtlike activity. This notion is explored slightly less wildly in the following dialogue, in which consciousness emerges from the interacting levels of an ant colony.

D. R. H.

11 Douglas R. Hofstadter Prelude … Ant Fugue[15]

Achilles and the Tortoise have come to the residence of their friend the Crab, to make the acquaintance of one of his friends, the Anteater. The introductions having been made, the four of them settle down to tea.

TORTOISE: We have brought along a little something for you, Mr. Crab.

CRAB: That’s most kind of you. But you shouldn’t have.

TORTOISE: Just a token of our esteem. Achilles, would you like to give it to Mr. C?

ACHILLES: Surely. Best wishes, Mr. Crab. I hope you enjoy it.

(Achilles hands the Crab an elegantly wrapped present, square and very thin. The Crab begins unwrapping it.)

ANTEATER: I wonder what it could be.

CRAB: We’ll soon find out. (Completes the unwrapping, and pulls out the gift.) Two records! How exciting! But there’s no label. Uh-oh-is this another of your “specials,” Mr. T?

TORTOISE: If you mean a phonograph-breaker, not this time. But it is in fact a custom-recorded item, the only one of its kind in the entire world. In fact, it’s never even been heard before—except, of course, when Bach played it.

CRAB: When Bach played it? What do you mean, exactly?

ACHILLES: Oh, you are going to be fabulously excited, Mr. Crab, when Mr. T tells you what these records in fact are.

TORTOISE: Oh, you go ahead and tell him, Achilles.

ACHILLES: May I? Oh, boy! I’d better consult my notes, then. (Pulls out a small filing card and clears his voice.) Ahem. Would you be interested in hearing about the remarkable new result in mathematics, to which your records owe their existence?

CRAB: My records derive from some piece of mathematics? How curious! Well, now that you’ve provoked my interest, I must hear about it.

ACHILLES: Very well, then. (Pauses for a moment to sip his tea, then resumes.) Have you heard of Fermat’s infamous “Last Theorem”?

ANTEATER: I’m not sure.... It sounds strangely familiar, and yet I can’t quite place it.

ACHILLES: It’s a very simple idea. Pierre de Fermat, a lawyer by vocation but mathematician by avocation, had been reading in his copy of the classic text Arithmetica by Diophantus and came across a page containing the equation

He immediately realized that this equation has infinitely many solutions a, b, c, and then wrote in the margin the following notorious comment:

Ever since that day, some three hundred years ago, mathematicians have been vainly trying to do one of two things: either to prove Fermat’s claim and thereby vindicate Fermat’s reputation, which, although very high, has been somewhat tarnished by skeptics who think he never really found the proof he claimed to have found—or else to refute the claim, by finding a counterexample: a set of four integers a, b, c, and n, with n > 2, which satisfy the equation. Until very recently, every attempt in either direction had met with failure. To be sure, the Theorem has been proven for many specific values of n—in particular, all n up to 125,000.

ANTEATER: Shouldn’t it be called a “Conjecture” rather than a “Theorem,” if it’s never been given a proper proof?

ACHILLES: Strictly speaking, you’re right, but tradition has kept it this way.

CRAB: Has someone at last managed to resolve this celebrated question?

ACHILLES: Indeed! In fact, Mr. Tortoise has done so, and as usual, by a wizardly stroke. He has not only found a proof of Fermat’s Last Theorem (thus justifying its name as well as vindicating Fermat), but also a counterexample, thus showing that the skeptics had good intuition!

CRAB: Oh my gracious! That is a revolutionary discovery.

ANTEATER: But please don’t leave us in suspense. What magical integers are they, that satisfy Fermat’s equation? I’m especially curious about the value of n.

ACHILLES: Oh, horrors! I’m most embarrassed! Can you believe this? I left the values at home on a truly colossal piece of paper. Unfortunately it was too huge to bring along. I wish I had them here to show to you. If it’s of any help to you, I do remember one thing—the value of n is the only positive integer which does not occur anywhere in the continued fraction for π.

CRAB: Oh, what a shame that you don’t have them here. But there’s no reason to doubt what you have told us.

ANTEATER: Anyway, who needs to see n written out decimally? Achilles has just told us how to find it. Well, Mr. T, please accept my hearty felicitations, on the occasion of your epoch-making discovery!

TORTOISE: Thank you. But what I feel is more important than the result itself is the practical use to which my result immediately led.

CRAB: I am dying to hear about it, since I always thought number theory was the Queen of Mathematics—the purest branch of mathematics—the one branch of mathematics which has no applications!

TORTOISE: You’re not the only one with that belief, but in fact it is quite impossible to make a blanket statement about when or how some branch—or even some individual Theorem—of pure mathematics will have important repercussions outside of mathematics. It is quite unpredictable—and this case is a perfect example of that phenomenon.

Pierre de Fermat

ACHILLES: Mr. Tortoise’s double-barreled result has created a breakthrough in the field of acoustico-retrieval!

ANTEATER: What is acoustico-retrieval?

ACHILLES: The name tells it all: it is the retrieval of acoustic information from extremely complex sources. A typical task of acoustico-retrieval is to reconstruct the sound which a rock made on plummeting into a lake, from the ripples which spread out over the lake’s surface.

CRAB: Why, that sounds next to impossible!

ACHILLES: Not so. It is actually quite similar to what one’s brain does, when it reconstructs the sound made in the vocal cords of another person from the vibrations transmitted by the eardrum to the fibers in the cochlea.

CRAB: I see. But I still don’t see where number theory enters the picture, or what this all has to do with my new records.

ACHILLES: Well, in the mathematics of acoustico-retrieval, there arise many questions which have to do with the number of solutions of certain Diophantine equations. Now Mr. T has been for years trying to find a way of reconstructing the sounds of Bach playing his harpsichord, which took place over two hundred years ago, from calculations involving the motions of all the molecules in the atmosphere at the present time.

ANTEATER: Surely that is impossible! They are irretrievably gone, gone forever!

ACHILLES: Thus think the naïve … But Mr. T has devoted many years to this problem, and came to the realization that the whole thing hinged on the number of solutions to the equation

in positive integers, with n > 2.

TORTOISE: I could explain, of course, just how this equation arises, but I’m sure it would bore you.

ACHILLES: It turned out that acoustico-retrieval theory predicts that the Bach sounds can be retrieved from the motion of all the molecules in the atmosphere, provided that there exists either at least one solution to the equation—

CRAB: Amazing!

ANTEATER: Fantastic!

TORTOISE: Who would have thought!

ACHILLES: I was about to say, “provided that there exists either such a solution or a proof that there are no solutions!” And therefore, Mr. T, in careful fashion, set about working at both ends of the problem simultaneously. As it turns out, the discovery of the counterexample was the key ingredient to finding the proof, so the one led directly) to the other.

CRAB: How could that be?

TORTOISE: Well, you see, I had shown that the structural layout of any proof of Fermat’s Last Theorem—if one existed—could be described by an elegant formula, which, it so happened, depended on the values of a solution to a certain equation. When I found this second equation, to my surprise it turned out to be the Fermat equation. An amusing accidental relationship between form and content. So when I found the counterexample, all I needed to do was to use those numbers as, a blueprint for constructing my proof that there were no solutions to the equation. Remarkably simple, when you think about it. I can’t imagine why no one had ever found the result before.

ACHILLES: As a result of this unanticipatedly rich mathematical success, Mr. T was able to carry out the acoustico-retrieval which he had so long dreamed of. And Mr. Crab’s present here represents a palpable realization of all this abstract work.

CRAB: Don’t tell me it’s a recording of Bach playing his own works for harpsichord!

ACHILLES: I’m sorry, but I have to, for that is indeed just what it is! This is a set of two records of Johann Sebastian Bach playing all of his Well-Tempered Clavier. Each record contains one of the two volumes of the Well-Tempered Clavier; that is to say, each record contains twenty-four preludes and fugues—one in each major and minor key.

CRAB: Well, we must absolutely put one of these priceless records on, immediately! And how can I ever thank the two of you?

TORTOISE: You have already thanked us plentifully, with this delicious tea which you have prepared.

(The Crab slides one of the records out of its jacket and puts it on. The sound of an incredibly masterful harpsichordist fills the room, in the highest imaginable fidelity. One even hears—or is it one’s imagination?—the soft sounds of Bach singing to himself as he plays....)

CRAB: Would any of you like to follow along in the score? I happen to have a unique edition of the Well-Tempered Clavier, specially illuminated by a teacher of mine who happens also to be an unusually fine calligrapher.

TORTOISE: I would very much enjoy that.

(The Crab goes to his elegant glass-enclosed wooden bookcase, opens the doors, and draws out two large volumes.)

CRAB: Here you are, Mr. Tortoise. I’ve never really gotten to know all the beautiful illustrations in this edition. Perhaps your gift will provide the needed impetus for me to do so.

TORTOISE: I do hope so.

ANTEATER: Have you ever noticed how in these pieces the prelude always sets the mood perfectly for the following fugue?

CRAB: Yes. Although it may be hard to put it into words, there is always some subtle relation between the two. Even if the prelude and fugue do not have a common melodic subject, there is nevertheless always some intangible abstract quality which underlies both of them, binding them together very strongly.

TORTOISE: And there is something very dramatic about the few moments of silent suspense hanging between prelude and fugue—that moment where the theme of the fugue is about to ring out, in single tones, and then to join with itself in ever-increasingly complex levels of weird, exquisite harmony.

ACHILLES: I know just what you mean. There are so many preludes and fugues which I haven’t yet gotten to know, and for me that fleeting interlude of silence is very exciting; it’s a time when I try to second-guess old Bach. For example, I always wonder what the fugue’s tempo will be: allegro or adagio? Will it be in 6/8 or 4/4? Will it have three voices or five—or four? And then, the first voice starts.... Such an exquisite moment.

CRAB: Ah, yes, well do I remember those long-gone days of my youth, the days when I thrilled to each new prelude and fugue, filled with the excitement of their novelty and beauty and the many unexpected surprises which they conceal.

ACHILLES: And now? Is that thrill all gone?

CRAB: It’s been supplanted by familiarity, as thrills always will be. But in that familiarity there is also a kind of depth, which has its own compensations. For instance, I find that there are always new surprises which I hadn’t noticed before.

ACHILLES: Occurrences of the theme which you had overlooked?

CRAB: Perhaps—especially when it is inverted and hidden among several other voices, or where it seems to come rushing up from the depths, out of nowhere. But there are also amazing modulations which it is marvelous to listen to over and over again, and wonder how old Bach dreamt them up.

ACHILLES: I am very glad to hear that there is something to look forward to, after I have been through the first flush of infatuation with the Well-Tempered Clavier—although it also makes me sad that this stage could not last forever and ever.

CRAB: Oh, you needn’t fear that your infatuation will totally die. One of the nice things about that sort of youthful thrill is that it can always be resuscitated, just when you thought it was finally dead. It just takes the right kind of triggering from the outside.

ACHILLES: Oh, really? Such as what?

CRAB: Such as hearing it through the ears, so to speak, of someone to whom it is a totally new experience—someone such as you, Achilles. Somehow the excitement transmits itself, and I can feel thrilled again.

ACHILLES: That is intriguing. The thrill has remained dormant somewhere inside you, but by yourself, you aren’t able to fish it up out of your subconscious.

CRAB: Exactly. The potential of reliving the thrill is “coded,” in some unknown way, in the structure of my brain, but I don’t have the power to summon it up at will; I have to wait for chance circumstance to trigger it.

ACHILLES: I have a question about fugues which I feel a little embarrassed about asking, but as I am just a novice at fugue-listening, I was wondering if perhaps one of you seasoned fugue-listeners might help me in learning? …

TORTOISE: I’d certainly like to offer my own meager knowledge, if it might prove of some assistance.

ACHILLES: Oh, thank you. Let me come at the question from an angle. Are you familiar with the print called Cube with Magic Ribbons, by M. C. Escher?

TORTOISE: In which there are circular bands having bubblelike distortions which, as soon as you’ve decided that they are bumps, seem to turn into dents—and vice versa?

ACHILLES: Exactly.

CRAB: I remember that picture. Those little bubbles always seem to flip back and forth between being concave and convex, depending on the direction that you approach them from. There’s no way to see them simultaneously as concave and convex—somehow one’s brain doesn’t allow that. There are two mutually exclusive “modes” in which one can perceive the bubbles.

ACHILLES: Just so. Well, I seem to have discovered two somewhat analogous modes in which I can listen to a fugue. The modes are these: either to follow one individual voice at a time, or to listen to the total effect of all of them together, without trying to disentangle one from another. I have tried out both of these modes, and, much to my frustration, each one of them shuts out the other. It’s simply not in my power to follow the paths of individual voices and at the same time to hear the whole effect. I find that I flip back and forth between one mode and the other, more or less spontaneously and involuntarily.

Cube with Magic Ribbons (M. C. Escher, lithograph, 1957)

ANTEATER: Just as when you look at the magic bands, eh?

ACHILLES: Yes. I was just wondering… does my description of these two modes of fugue-listening brand me unmistakably as a naïve, inexperienced listener, who couldn’t even begin to grasp the deeper modes of perception which exist beyond his ken?

TORTOISE: No, not at all, Achilles. I can only speak for myself, but I too find myself shifting back and forth from one mode to the other without exerting any conscious control over which mode should be dominant. I don’t know if our other companions here have also experienced anything similar.

CRAB: Most definitely. It’s quite a tantalizing phenomenon, since you feel that the essence of the fugue is flitting about you, and you can’t quite grasp all of it, because you can’t quite make yourself function both ways at once.

ANTEATER: Fugues have that interesting property, that each of their voices is a piece of music in itself; and thus a fugue might be thought of as a collection of several distinct pieces of music, all based on one single theme, and all played simultaneously. And it is up to the listener (or his subconscious) to decide whether it should be perceived as a unit, or as a collection of independent parts, all of which harmonize.

ACHILLES: You say that the parts are “independent,” yet that can’t be literally true. There has to be some coordination between them, otherwise when they were put together one would just have an unsystematic clashing of tones—and that is as far from the truth as could be.

ANTEATER: A better way to state it might be this: if you listened to each voice on its own, you would find that it seemed to make sense all by itself. It could stand alone, and that is the sense in which I meant that it is independent. But you are quite right in pointing out that each of these individually meaningful lines fuses with the others in a highly nonrandom way, to make a graceful totality. The art of writing a beautiful fugue lies precisely in this ability, to manufacture several different lines, each one of which gives the illusion of having been written for its own beauty, and yet which when taken together form a whole, which does not feel forced in any way. Now, this dichotomy, between hearing a fugue as a whole and hearing its component voices is a particular example of a very general dichotomy, which applies to many kinds of structures built up from lower levels.

ACHILLES: Oh, really? You mean that my two “modes” may have some more general type of applicability, in situations other than fugue-listening?

ANTEATER: Absolutely.

ACHILLES: I wonder how that could be. I guess it has to do with alternating between perceiving something as a whole and perceiving it as a collection of parts. But the only place I have ever run into that dichotomy is in listening to fugues.

TORTOISE: Oh, my, look at this! I just turned the page while following the music, and came across this magnificent illustration facing the first page of the fugue.

CRAB: I have never seen that illustration before. Why don’t you pass it ’round?

(The Tortoise passes the book around. Each of the foursome looks at it in a characteristic way—this one from afar, that one from close up, everyone tipping his head this way and that in puzzlement. Finally it has made the rounds and returns to the Tortoise, who peers at it rather intently. )

ACHILLES: Well, I guess the prelude is just about over. I wonder if, as I listen to this fugue, I will gain any more insight into the question “What is the right way to listen to a fugue: as a whole, or as the sum of its parts?”

TORTOISE: Listen carefully, and you will!

(The prelude ends. There is a moment of silence; and …

[ATTACCA ]

…then, one by one, the four voices of the fugue chime in.)

ACHILLES: I know the rest of you won’t believe this, but the answer to the question is staring us all in the face, hidden in the picture. It is simply one word—but what an important one: “MU”!

CRAB: I know the rest of you won’t believe this, but the answer to the question is staring us all in the face, hidden in the picture. It is simply one word—but what an important one: “HOLISM”!

ACHILLES: Now hold on a minute. You must be seeing things. It’s plain as day that the message of this picture is “MU,” not “HOLISM”!

CRAB: I beg your pardon, but my eyesight is extremely good. Please look again, and then tell me if the picture doesn’t say what I said it says!

ANTEATER: I know the rest of you won’t believe this, but the answer to the question is staring us all in the face, hidden in the picture. It is simply one word—but what an important one: “REDUCTIONISM”!

CRAB: Now hold on a minute. You must be seeing things. It’s plain as day that the message of this picture is “HOLISM,” not “REDUCTIONISM”!

ACHILLES: Another deluded one! Not “HOLISM,” not “REDUCTIONISM,” but “MU” is the message of this picture, and that much is certain.

ANTEATER: I beg your pardon, but my eyesight is extremely clear. Please look again, and then see if the picture doesn’t say what I said it says.

ACHILLES: Don’t you see that the picture is composed of two pieces, and that each of them is a single letter?

CRAB: You are right about the two pieces, but you are wrong in your identification of what they are. The piece on the left is entirely composed of three copies of one word: “HOLISM”; and the piece on the right is composed of many copies, in smaller letters, of the same word. Why the letters are of different sizes in the two parts, I don’t know, but I know what I see, and what I see is “HOLISM,” plain as day. How you see anything else is beyond me.

ANTEATER: You are right about the two pieces, but you are wrong in your identification of what they are. The piece on the left is entirely composed of many copies of one word: “REDUCTIONISM”; and the piece on the right is composed of one single copy, in larger letters, of the same word. Why the letters are of different sizes in the two parts, I don’t know, but I know what I see, and what I see is “REDUCTIONISM,” plain as day. How you see anything else is beyond me.

ACHILLES: I know what is going on here. Each of you has seen letters which compose, or are composed of, other letters. In the left-hand piece, there are indeed three “HOLISM”s, but each one of them is composed out of smaller copies of the word “REDUCTIONISM.” And in complementary fashion, in the right-hand piece, there is indeed one “REDUCTIONISM,” but it is composed out of smaller copies of the word “HOLISM.” Now this is all fine and good, but in your silly squabble, the two of you have actually missed the forest for the trees. You see, what good is it to argue about whether “HOLISM” or “REDUCTIONISM” is right, when the proper way to understand the matter is to transcend the question, by answering “MU”?

CRAB: I now see the picture as you have described it, Achilles, but I have no idea of what you mean by the strange expression “transcending the question.”

ANTEATER: I now see the picture as you have described it, Achilles, but I have no idea of what you mean by the strange expression “mu.”

ACHILLES: I will be glad to indulge both of you, if you will first oblige me, by telling me the meaning of these strange expressions, “holism” and “reductionism.”

CRAB: Holism is the most natural thing in the world to grasp. It’s simply the belief that “the whole is greater than the sum of its parts.” No one in his right mind could reject holism.

ANTEATER: Reductionism is the most natural thing in the world to grasp. It’s simply the belief that “a whole can be understood completely if you understand its parts, and the nature of their ‘sum.’ ” No one in her left brain could reject reductionism.

CRAB: I reject reductionism. I challenge you to tell me, for instance, how to understand a brain reductionistically. Any reductionistic explanation of a brain will inevitably fall far short of explaining where the consciousness experienced by a brain arises from.

ANTEATER: I reject holism. I challenge you to tell me, for instance, how a holistic description of an ant colony sheds any more light on it than is shed by a description of the ants inside it, and their roles, and their, interrelationships. Any holistic explanation of an ant colony will inevitably fall far short of explaining where the consciousness experienced by an ant colony arises from.

ACHILLES: Oh, no! The last thing that I wanted to do was to provoke another argument. Anyway, now that I understand the controversy, I believe that my explanation of “mu” will help greatly. You see “mu” is an ancient Zen answer which, when given to a question, unasks the question. Here, the question seems to be “Should the world be understood via holism or via reductionism?” And the answer of “mu” here rejects the premises of the question, which are that one or the other must be chosen. By unasking the question, it reveals a wider truth: that there is a larger context into which both holistic and reductionistic explanations fit.

ANTEATER: Absurd! Your “mu” is as silly as a cow’s moo. I’ll have none of this Zen wishy-washiness.

CRAB: Ridiculous! Your “mu” is as silly as a kitten’s mew. I’ll have none of this Zen washy-wishiness.

ACHILLES: Oh, dear! We’re getting nowhere fast. Why have you stayed so strangely silent, Mr. Tortoise? It makes me very uneasy. Surely you must somehow be capable of helping straighten out this mess?

TORTOISE: I know the rest of you won’t believe this, but the answer to the question is staring us all in the face, hidden in the picture. It is simply one word—but what an important one: “MU”!

(Just as he says this, the fourth voice in the fugue being played enters, exactly one octave below the first entry.)

ACHILLES: Oh, Mr. T, for once you have let me down. I was sure that you, who always see the most deeply into things, would be able resolve this dilemma—but apparently, you have seen no further than I myself saw. Oh, well, I guess I should feel pleased to have seer far as Mr. Tortoise, for once.

TORTOISE: I beg your pardon, but my eyesight is extremely fine. Please look again, and then tell me if the picture doesn’t say what I said says.

ACHILLES: But of course it does! You have merely repeated my own original observation.

TORTOISE: Perhaps “MU” exists in this picture on a deeper level than imagine, Achilles—an octave lower (figuratively speaking). But now I doubt that we can settle the dispute in the abstract. I would like to see both the holistic and reductionistic points of view laid more explicitly; then there may be more of a basis for a decision. I would very much like to hear a reductionistic description of an colony, for instance.

CRAB: Perhaps Dr. Anteater will tell you something of his experiences in that regard. After all, he is by profession something of an expert on that subject.

TORTOISE: I am sure that we could learn much from a myrmecologist you, Dr. Anteater. Could you tell us more about ant colonies, from a reductionistic point of view?

ANTEATER: Gladly. As Mr. Crab mentioned to you, my profession has me quite a long way into the understanding of ant colonies.

ACHILLES: I can imagine! The profession of Anteater would seem to be synonymous with being an expert on ant colonies!

ANTEATER: I beg your pardon. “Anteater” is not my profession; it is species. By profession, I am a colony surgeon. I specialize in correcting nervous disorders of the colony by the technique of surgical removal.

ACHILLES: Oh, I see. But what do you mean by “nervous disorders” of an ant colony?

ANTEATER: Most of my clients suffer from some sort of speech impairment. You know, colonies which have to grope for words in every situations. It can be quite tragic. I attempt to remedy the situation by, uhh—removing—the defective part of the colony. These operations are sometimes quite involved, and of course years of study are required before one can perform them.

ACHILLES: But—isn’t it true that, before one can suffer from speech impairment, one must have the faculty of speech?

ANTEATER: Right.

ACHILLES: Since ant colonies don’t have that faculty, I am a little confused.

CRAB: It’s too bad, Achilles, that you weren’t here last week, when Dr. Anteater and Aunt Hillary were my house guests. I should have thought of having you over then.

ACHILLES: Is Aunt Hillary your aunt, Mr. Crab?

CRAB: Oh, no, she’s not really anybody’s aunt.

ANTEATER: But the poor dear insists that everybody should call her that, even strangers. It’s just one of her many endearing quirks.

CRAB: Yes, Aunt Hillary is quite eccentric, but such a merry old soul. It’s a shame I didn’t have you over to meet her last week.

ANTEATER: She’s certainly one of the best-educated ant colonies I have ever had the good fortune to know. The two of us have spent many a long evening in conversation on the widest range of topics.

ACHILLES: I thought anteaters were devourers of ants, not patrons of ant-intellectualism!

ANTEATER: Well, of course the two are not mutually inconsistent. I am on the best of terms with ant colonies. It’s just ants that I eat, not colonies—and that is good for both parties: me, and the colony.

ACHILLES: How is it possible that —

TORTOISE: How is it possible that —

ACHILLES: —having its ants eaten can do an ant colony any good?

CRAB: How is it possible that —

TORTOISE: —having a forest fire can do a forest any good?

ANTEATER: How is it possible that —

CRAB: —having its branches pruned can do a tree any good?

ANTEATER: —having a haircut can do Achilles any good?

TORTOISE: Probably the rest of you were too engrossed in the discussion to notice the lovely stretto which just occurred in this Bach fugue.

ACHILLES: What is a stretto?

TORTOISE: Oh, I’m sorry; I thought you knew the term. It is where one theme repeatedly enters in one voice after another, with very little delay between entries.

ACHILLES: If I listen to enough fugues, soon I’ll know all of these things and will be able to pick them out myself, without their having to be pointed out.

TORTOISE: Pardon me, my friends. I am sorry to have interrupted. Dr. Anteater was trying to explain how eating ants is perfectly consistent with being a friend of an ant colony.

ACHILLES: Well, I can vaguely see how it might be possible for a limited and regulated amount of ant consumption to improve the overall health of a colony—but what is far more perplexing is all this talk about having conversations with ant colonies. That’s impossible. An ant colony is simply a bunch of individual ants running around at random looking for food and making a nest.

ANTEATER: You could put it that way if you want to insist on seeing the trees but missing the forest, Achilles. In fact, ant colonies, seen as wholes, are quite well-defined units, with their own qualities, at times including the mastery of language.

ACHILLES: I find it hard to imagine myself shouting something out loud in the middle of the forest, and hearing an ant colony answer back.

ANTEATER: Silly fellow! That’s not the way it happens. Ant colonies don’t converse out loud, but in writing. You know how ants form trails leading them hither and thither?

ACHILLES: Oh, yes—usually straight through the kitchen sink and into my peach jam.

ANTEATER: Actually, some trails contain information in coded form. If you know the system, you can read what they’re saying just like a book.

ACHILLES: Remarkable. And can you communicate back to them?

ANTEATER: Without any trouble at all. That’s how Aunt Hillary and I have conversations for hours. I take a stick and draw trails in the moist ground, and watch the ants follow my trails. Presently, a new trail starts getting formed somewhere. I greatly enjoy watching trails develop. As they are, forming, I anticipate how they will continue (and more often I am wrong than right). When the trail is completed, I know what Aunt Hillary is thinking, and I in turn make my reply.

ACHILLES: There must be some amazingly smart ants in that colony, I’ll say that.

ANTEATER: I think you are still having some difficulty realizing the difference in levels here. Just as you would never confuse an individual tree with a forest, so here you must not take an ant for the colony. You see, all the ants in Aunt Hillary are as dumb as can be. They couldn’t converse to save their little thoraxes!

ACHILLES: Well then, where does the ability to converse come from? It must reside somewhere inside the colony! I don’t understand how the ants can all be unintelligent, if Aunt Hillary can entertain you for hours with witty banter.

TORTOISE: It seems to me that the situation is not unlike the composition of a human brain out of neurons. Certainly no one would insist that individual brain cells have to be intelligent beings on their own, in order to explain the fact that a person can have an intelligent conversation.

ACHILLES: Oh, no, clearly not. With brain cells, I see your point completely. Only… ants are a horse of another color. I mean, ants just roam about at will, completely randomly, chancing now and then upon a morsel of food.... They are free to do what they want to do, and with that freedom, I don’t see at all how their behavior, seen as a whole, can amount to anything coherent—especially something so coherent as the brain behavior necessary for conversing.

CRAB: It seems to me that the ants are free only within certain constraints. For example, they are free to wander, to brush against each other, to pick up small items, to work on trails, and so on. But they never step out of that small world, that ant-system, which they are in. It would never occur to them, for they don’t have the mentality to imagine anything of the kind. Thus the ants are very reliable components, in the sense that you can depend on them to perform certain kinds of tasks in certain ways.

ACHILLES: But even so, within those limits they are still free, and they just act at random, running about incoherently without any regard for the thought mechanisms of a higher-level being which Dr. Anteater asserts they are merely components of.

ANTEATER: Ah, but you fail to recognize one thing, Achilles—the regularity of statistics.

ACHILLES: How is that?

ANTEATER: For example, even though ants as individuals wander about in what seems a random way, there are nevertheless overall trends, involving large numbers of ants, which can emerge from that chaos.

ACHILLES: Oh, I know what you mean. In fact, ant trails are a perfect example of such a phenomenon. There, you have really quite unpredictable motion on the part of any single ant—and yet, the trail itself seems to remain well defined and stable. Certainly that must mean that the individual ants are not just running about totally at random.

ANTEATER: Exactly, Achilles. There is some degree of communication among the ants, just enough to keep them from wandering off completely at random. By this minimal communication they can remind each other that they are not alone but are cooperating with teammates. It takes a large number of ants, all reinforcing each other this way, to sustain any activity—such as trail building—for any length of time. Now my very hazy understanding of the operation of brains leads me to believe that something similar pertains to the firing of neurons. Isn’t it true, Mr. Crab, that it takes a group of neurons firing in order to make another neuron fire?

CRAB: Definitely. Take the neurons in Achilles’ brain, for example. Each neuron receives signals from neurons attached to its input lines, and if the sum total of inputs at any moment exceeds a critical threshold, then that neuron will fire and send its own output pulse rushing off to other neurons, which may in turn fire—and on down the line it goes. The neural flash swoops relentlessly in its Achillean path, in shapes stranger then the dash of a gnat-hungry swallow; every twist, every turn foreordained by the neural structure in Achilles’ brain, until sensory input messages interfere.

ACHILLES: Normally, I think that I’m in control of what I think—but the way you put it turns it all inside out, so that it sounds as though “I” am just what comes out of all this neural structure, and natural law. It makes what I consider my self sound at best like a by-product of an organism governed by natural law and, at worst, an artificial notion produced by my distorted perspective. In other words, you make me feel like I don’t know who—or what—I am, if anything.

TORTOISE: You’ll come to understand much better as we go along. But Dr. Anteater—what do you make of this similarity?

ANTEATER: I knew there was something parallel going on in the two very different systems. Now I understand it much better. It seems that group phenomena which have coherence—trail building, for example—will take place only when a certain threshold number of ants get involved. If an effort is initiated, perhaps at random, by a few ants in some locale, one of two things can happen: either it will fizzle out after a brief sputtering start —

ACHILLES: When there aren’t enough ants to keep the thing rolling?

ANTEATER: Exactly. The other thing that can happen is that a critical mass of ants is present, and the thing will snowball, bringing more and more ants into the picture. In the latter case, a whole “team” is brought into being which works on a single project. That project might be trail making, or food gathering, or it might involve nest keeping. Despite the extreme simplicity of this scheme on a small scale, it can give rise to very complex consequences on a larger scale.

ACHILLES: I can grasp the general idea of order emerging from chaos, as you sketch it, but that still is a long way from the ability to converse. After all, order also emerges from chaos when molecules of a gas bounce against each other randomly—yet all that results there is an amorphous mass with but three parameters to characterize it: volume, pressure, and temperature. Now that’s a far cry from the ability to understand the world, or to talk about it!

ANTEATER: That highlights a very interesting difference between the explanation of the behavior of an ant colony and the explanation of the behavior of gas inside a container. One can explain the behavior of the gas simply by calculating the statistical properties of the motions of its molecules. There is no need to discuss any higher elements of structure than molecules, except the full gas itself. On the other hand, in an ant colony, you can’t even begin to understand the activities of the colony unless you go through several layers of structure.

ACHILLES: I see what you mean. In a gas, one jump takes you from the lowest level—molecules—to the highest level—the full gas. There are no intermediate levels of organization. Now how do intermediate levels of organized activity arise in an ant colony?

ANTEATER: It has to do with the existence of several different varieties of ants inside any colony.

ACHILLES: Oh, yes. I think I have heard about that. They are called “castes,” aren’t they?

ANTEATER: That’s correct. Aside from the queen, there are males, who do practically nothing toward the upkeep of the nest, and then —

ACHILLES: And of course there are soldiers—glorious fighters against communism!

CRAB: Hmm… I hardly think that could be right, Achilles. An ant colony is quite communistic internally, so why would its soldiers fight against communism? Or am I right, Dr. Anteater?

ANTEATER: Yes, about colonies you are right, Mr. Crab; they are indeed based on somewhat communistic principles. But about soldiers Achilles is somewhat naïve. In fact, the so-called “soldiers” are hardly adept at fighting at all. They are slow, ungainly ants with giant heads, who can snap with their strong jaws, but are hardly to be glorified. As in a true communistic state, it is rather the workers who are to be glorified. It is they who do most of the chores, such as food gathering, hunting, and nursing of the young. It is even they who do most of the fighting.

ACHILLES: Bah. That is an absurd state of affairs. Soldiers who won’t fight!

ANTEATER: Well, as I just said, they really aren’t soldiers at all. It’s the workers who are soldiers; the soldiers are just lazy fatheads.

ACHILLES: Oh, how disgraceful! Why, if I were an ant, I’d put some discipline in their ranks! I’d knock some sense into those fatheads!

TORTOISE: If you were an ant? How could a myrmidon like you be an ant? There is no way to map your brain onto an ant brain, so it seems to me to be a pretty fruitless question to worry over. More reasonable would be the proposition of mapping your brain onto an ant colony. … But let us not get sidetracked. Let Dr. Anteater continue with his most illuminating description of castes and their role in the higher levels of organization.

ANTEATER: Very well. There are all sorts of tasks which must be accomplished in a colony, and individual ants develop specializations. Usually an ant’s specialization changes as the ant ages. And of course it is also dependent on the ant’s caste. At any one moment, in any small area of a colony, there are ants of all types present. Of course, one caste may be be very sparse in some places and very dense in others.

CRAB: Is the density of a given caste, or specialization, just a random thing? Or is there a reason why ants of one type might be more heavily concentrated in certain areas, and less heavily in others?

ANTEATER: I’m glad you brought that up, since it is of crucial importance in understanding how a colony thinks. In fact, there evolves, over a long period of time, a very delicate distribution of castes inside a colony. And it is this distribution that allows the colony to have the complexity that underlies the ability to converse with me.

ACHILLES: It would seem to me that the constant motion of ants to and fro would completely prevent the possibility of a very delicate distribution. Any delicate distribution would be quickly destroyed by all the random motions of ants, just as any delicate pattern among molecules in a gas would not survive for an instant, due to the random bombardment from all sides.

ANTEATER: In an ant colony, the situation is quite the contrary. In fact, it is just exactly the constant to-ing and fro-ing of ants inside the colony which adapts the caste distribution to varying situations, and thereby preserves the delicate caste distribution. You see, the caste distribution cannot remain as one single rigid pattern; rather, it must constantly be changing so as to reflect, in some manner, the real-world situation with which the colony is dealing, and it is precisely the motion inside the colony which updates the caste distribution, so as to keep it in line with the present circumstances facing the colony.

TORTOISE: Could you give an example?

ANTEATER: Gladly. When I, an anteater, arrive to pay a visit to Aunt Hillary, all the foolish ants, upon sniffing my odor, go into a panic—which means, of course, that they begin running around completely differently from the way they were before I arrived.

ACHILLES: But that’s understandable, since you’re a dreaded enemy of the colony.

ANTEATER: Oh, no. I must reiterate that, far from being an enemy of the colony, I am Aunt Hillary’s favorite companion. And Aunt Hillary is, my favorite aunt. I grant you, I’m quite feared by all the individual ants in the colony—but that’s another matter entirely. In any case, you see that the ants’ action in response to my arrival completely changes the internal distribution of ants.

ACHILLES: That’s clear.

ANTEATER: And that sort of thing is the updating which I spoke of. The new distribution reflects my presence. One can describe the change from old state to new as having added a “piece of knowledge” to the colony.

ACHILLES: How can you refer to the distribution of different types of ants inside a colony as a “piece of knowledge”?

ANTEATER: Now there’s a vital point. It requires some elaboration. You see, what it comes down to is how you choose to describe the caste distribution. If you continue to think in terms of the lower levels—individual ants—then you miss the forest for the trees. That’s just toy microscopic a level, and when you think microscopically, you’re bound to miss some large-scale features. You’ve got to find the proper high-level framework in which to describe the caste distribution—only then will it make sense how the caste distribution cal encode many pieces of knowledge.

ACHILLES: Well, how do you find the proper-sized units in which to describe the present state of the colony, then?

ANTEATER: All right. Let’s begin at the bottom. When ants need to get something done, they form little “teams,” which stick together to perform a chore. As I mentioned earlier, small groups of ants are constantly forming and unforming. Those which actually exist for while are the teams, and the reason they don’t fall apart is that there really is something for them to do.

ACHILLES: Earlier you said that a group will stick together if its size exceeds a certain threshold. Now you’re saying that a group will stick together if there is something for it to do.

ANTEATER: They are equivalent statements. For instance, in food gathering, if there is an inconsequential amount of food somewhere which gets discovered by some wandering ant who then attempts to communicate its enthusiasm to other ants, the number of ants who respond will be proportional to the size of the food sample—and a inconsequential amount will not attract enough ants to surpass the threshold. Which is exactly what I meant by saying there is nothing to do—too little food ought to be ignored.

ACHILLES: I see. I assume that these “teams” are one of the levels c structure falling somewhere in between the single-ant level and the colony level.

ANTEATER: Precisely. There exists a special kind of team, which I call “signal”—and all the higher levels of structure are based on signal. In fact, all the higher entities are collections of signals acting is concert. There are teams on higher levels whose members are no ants, but teams on lower levels. Eventually you reach the lowest-level teams—which is to say, signals—and below them, ants.

ACHILLES: Why do signals deserve their suggestive name?

ANTEATER: It comes from their function. The effect of signals is to traps port ants of various specializations to appropriate parts of the colony. So the typical story of a signal is thus: It comes into existence by exceeding the threshold needed for survival, then it migrates for some distance through the colony, and at some point it more or less disintegrates into its individual members, leaving them on their own.

ACHILLES: It sounds like a wave, carrying sand dollars and seaweed from afar, and leaving them strewn, high and dry, on the shore.

ANTEATER: In a way that’s analogous, since the team does indeed deposit something which it has carried from a distance, but whereas the water in the wave rolls back to the sea, there is no analogous carrier substance in the case of a signal, since the ants themselves compose it.

TORTOISE: And I suppose that a signal loses its coherency just at some spot in the colony where ants of that type were needed in the first place.

ANTEATER: Naturally.

ACHILLES: Naturally? It’s not so obvious to me that a signal should always go just where it is needed. And even if it goes in the right direction, how does it figure out where to decompose? How does it know it has arrived?

ANTEATER: Those are extremely important matters, since they involve explaining the existence of purposeful behavior—or what seems to be purposeful behavior—on the part of signals. From the description, one would be inclined to characterize the signals’ behavior as being oriented toward filling a need, and to call it “purposeful.” But you can look at it otherwise.

ACHILLES: Oh, wait. Either the behavior is purposeful, or it is not. I don’t see how you can have it both ways.

ANTEATER: Let me explain my way of seeing things, and then see if you agree. Once a signal is formed, there is no awareness on its part that it should head off in any particular direction. But here the delicate caste distribution plays a crucial role. It is what determines the motion of signals through the colony, and also how long a signal will remain stable, and where it will “dissolve.”

ACHILLES: So everything depends on the caste distribution, eh?

ANTEATER: Right. Let’s say a signal is moving along. As it goes, the ants which compose it interact, either by direct contact or by exchange of scents, with ants of the local neighborhoods which it passes through. The contacts and scents provide information about local matters of urgency, such as nest building, or nursing, or whatever. The signal will remain glued together as long as the local needs are different from what it can supply; but if it can contribute, it disintegrates, spilling a fresh team of usable ants onto the scene. Do you see now how the caste distribution acts as an overall guide of the teams inside the colony?

ACHILLES: I do see that.

ANTEATER: And do you see how this way of looking at things requires attributing no sense of purpose to the signal?

ACHILLES: I think so. Actually, I’m beginning to see things from two different vantage points. From an ant’s-eye point of view, a signal has no purpose. The typical ant in a signal is just meandering around the colony, in search of nothing in particular, until it finds that it feels like stopping. Its teammates usually agree, and at that moment the team unloads itself by crumbling apart, leaving just its members but none of its coherency. No planning is required, no looking ahead; nor is any search required to determine the proper direction. But from the colony’s point of view, the team has just responded to a message which was written in the language of the caste distribution. Now from this perspective, it looks very much like purposeful activity.

CRAB: What would happen if the caste distribution were entirely random? Would signals still band and disband?

ANTEATER: Certainly. But the colony would not last long, due to the meaninglessness of the caste distribution.

CRAB: Precisely the point I wanted to make. Colonies survive because their caste distribution has meaning, and that meaning is a holistic aspect, invisible on lower levels. You lose explanatory power unless you take that higher level into account.

ANTEATER: I see your side; but I believe you see things too narrowly.

CRAB: How so?

ANTEATER: Ant colonies have been subjected to the rigors of evolution for billions of years. A few mechanisms were selected for, and most were selected against. The end result was a set of mechanisms which make ant colonies work as we have been describing. If you could watch the whole process in a movie—running a billion or so times faster than life, of course—the emergence of various mechanisms would be seen as natural responses to external pressures, just as bubbles in boiling water are natural responses to an external heat source. I don’t suppose you see “meaning” and “purpose” in the bubbles in boiling water—or do you?

CRAB: No, but —

ANTEATER: Now that’s my point. No matter how big a bubble is, it owes its existence to processes on the molecular level, and you can forget about any “higher-level laws.” The same goes for ant colonies and their teams. By looking at things from the vast perspective of evolution, you can drain the whole colony of meaning and purpose. They become superfluous notions.

ACHILLES: Why, then, Dr. Anteater, did you tell me that you talked with Aunt Hillary? It now seems that you would deny that she can talk or think at all.

ANTEATER: I am not being inconsistent, Achilles. You see, I have as much difficulty as anyone else in seeing things on such a grandiose time scale, so I find it much easier to change points of view. When I do so, forgetting about evolution and seeing things in the here and now, the vocabulary of teleology comes back: the meaning of the caste distribution and the purposefulness of signals. This not only happens when I think of ant colonies, but also when I think about my own brain and other brains. However, with some effort I can always remember the other point of view if necessary, and drain all these systems of meaning, too.

CRAB: Evolution certainly works some miracles. You never know the next trick it will pull out of its sleeve. For instance, it wouldn’t surprise me one bit if it were theoretically possible for two or more “signals” to pass through each other, each one unaware that the other one is also a signal; each one treating the other as if it were just part of the background population.

ANTEATER: It is better than theoretically possible; in fact it happens routinely!

ACHILLES: Hmm.... What a strange image that conjures up in my mind. I can just imagine ants moving in four different directions, some black, some white, criss-crossing, together forming an orderly pattern, almost like—like —

TORTOISE: A fugue, perhaps?

ACHILLES: Yes—that’s it! An ant fugue!

CRAB: An interesting image, Achilles. By the way, all that talk of boiling water made me think of tea. Who would like some more?

ACHILLES: I could do with another cup, Mr. C.

CRAB: Very good.

An “ant fugue” drawn by M. C. Escher (woodcut, 1953.)

ACHILLES: Do you suppose one could separate out the different visual “voices” of such an “ant fugue”? I know how hard it is for me—

TORTOISE: Not for me, thank you.

ACHILLES: —to track a single voice—

ANTEATER: I’d like some too, Mr. Crab —

ACHILLES: —in a musical fugue—

ANTEATER: —if it isn’t too much trouble.

ACHILLES: —when all of them—

CRAB: Not at all. Four cups of tea —

TORTOISE: Three!

ACHILLES: —are going at once.

CRAB: —coming right up!

ANTEATER: That’s an interesting thought, Achilles. But it’s unlikely that anyone could draw such a picture in a convincing way.

ACHILLES: That’s too bad.

TORTOISE: Perhaps you could answer this, Dr. Anteater. Does a signal, from its creation until its dissolution, always consist of the same set of ants?

ANTEATER: As a matter of fact, the individuals in a signal sometimes break off and get replaced by others of the same caste, if there are a few in the area. Most often, signals arrive at their disintegration points with nary an ant in common with their starting lineup.

CRAB: I can see that the signals are constantly affecting the caste distribution throughout the colony, and are doing so in response to the internal needs of the colony—which in turn reflect the external situation which the colony is faced with. Therefore the caste distribution as you said, Dr. Anteater, gets continually updated in a way which, ultimately reflects the outer world.

ACHILLES: But what about those intermediate levels of structure? You were saying that the caste distribution should best be pictured not in terms of ants or signals, but in terms of teams whose members were other teams, whose members were other teams, and so on until; you come down to the ant level. And you said that that was the key to understanding how it was possible to describe the caste distribution as encoding pieces of information about the world.

ANTEATER: Yes, we are coming to all that. I prefer to give teams of a sufficiently high level the name of “symbols.” Mind you, this sense of the word has some significant differences from the usual sense. My “symbols” are active subsystems of a complex system, and they are composed of lower-level active subsystems.... They are therefore quite different from passive symbols, external to the system, such as letters of the alphabet or musical notes, which sit there immobile waiting for an active system to process them.

ACHILLES: Oh, this is rather complicated, isn’t it? I just had no idea that ant colonies had such an abstract structure.

ANTEATER: Yes, it’s quite remarkable. But all these layers of structure are necessary for the storage of the kinds of knowledge which enable an organism to be “intelligent” in any reasonable sense of the word. Any system which has a mastery of language has essentially the same underlying sets of levels.

ACHILLES: Now just a cotton-picking minute. Are you insinuating that my brain consists of, at bottom, just a bunch of ants running around?

ANTEATER: Oh, hardly. You took me a little too literally. The lowest level may be utterly different. Indeed, the brains of anteaters, for instance, are not composed of ants. But when you go up a level or two in a brain, you reach a level whose elements have exact counterparts in other systems of equal intellectual strength—such as ant colonies.

TORTOISE: That is why it would be reasonable to think of mapping your brain, Achilles, onto an ant colony, but not onto the brain of a mere ant.

ACHILLES: I appreciate the compliment. But how would such a mapping be carried out? For instance, what in my brain corresponds to the low-level teams which you call signals?

ANTEATER: Oh, I but dabble in brains, and therefore couldn’t set up the map in its glorious detail. But—and correct me if I’m wrong, Mr. Crab—I would surmise that the brain counterpart to an ant colony’s signal is the firing of a neuron; or perhaps it is a larger-scale event, such as a pattern of neural firings.

CRAB: I would tend to agree. But don’t you think that, for the purposes of our discussion, delineating the exact counterpart is not in itself crucial, desirable though it might be? It seems to me that the main idea is that such a correspondence does exist, even if we don’t know exactly how to define it right now. I would only question one point, Dr. Anteater, which you raised, and that concerns the level at which one can have faith that the correspondence begins. You seemed to think that a signal might have a direct counterpart in a brain; whereas I feel that it is only at the level of your active symbols and above that it is likely that a correspondence must exist.

ANTEATER: Your interpretation may very well be more accurate than mine, Mr. Crab. Thank you for bringing out that subtle point.

ACHILLES: What does a symbol do that a signal couldn’t do?

ANTEATER: It is something like the difference between words and letters. Words, which are meaning-carrying entities, are composed of letters, which in themselves carry no meaning. This gives a good idea of the difference between symbols and signals. In fact it is a useful analogy, as long as you keep in mind the fact that words and letters are passive, symbols and signals are active.

ACHILLES: I’ll do so, but I’m not sure I understand why it is so vital to stress the difference between active and passive entities.

ANTEATER: The reason is that the meaning which you attribute to any passive symbol, such as a word on a page, actually derives from the meaning which is carried by corresponding active symbols in your brain. So that the meaning of passive symbols can only be properly understood when it is related to the meaning of active symbols.

ACHILLES: All right. But what is it that endows a symbol—an active one, to be sure—with meaning, when you say that a signal, which is a perfectly good entity in its own right, has none?

ANTEATER: It all has to do with the way that symbols can cause other symbols to be triggered. When one symbol becomes active, it does not do so in isolation. It is floating about, indeed, in a medium, which is characterized by its caste distribution.

CRAB: Of course, in a brain there is no such thing as a caste distribution, but the counterpart is the “brain state.” There, you describe the states of all the neurons, and all the interconnections, and the threshold for firing of each neuron.

ANTEATER: Very well; let’s lump “caste distribution” and “brain state” under a common heading, and call them just the “state.” Now the state can be described on a low level or on a high level. A low-level description of the state of an ant colony would involve painfully specifying the location of each ant, its age and caste, and other similar items. A very detailed description, yielding practically no global insight as to why it is in that state. On the other hand, a description on a high level would involve specifying which symbols could be triggered by which combinations of other symbols, under what conditions, and so forth.

ACHILLES: What about a description on the level of signals, or teams.

ANTEATER: A description on that level would fall somewhere in between the low-level and symbol-level descriptions. It would contain a great deal of information about what is actually going on in specific locations throughout the colony, although certainly less than an ant-by-ant description, since teams consist of clumps of ants. A team-by-team description is like a summary of an ant-by-ant description. However, you have to add extra things which were not present in the ant-by-ant description—such as the relationships between teams, and the supply of various castes here and there. This extra complication is the price you pay for the right to summarize.

ACHILLES: It is interesting to me to compare the merits of the descriptions at various levels. The highest-level description seems to carry the most explanatory power, in that it gives you the most intuitive picture of the ant colony, although strangely enough, it leaves out seemingly the most important feature—the ants.

ANTEATER: But you see, despite appearances, the ants are not the most important feature. Admittedly, were it not for them, the colony wouldn’t exist; but something equivalent—a brain—can exist, ant-free. So, at least from a high-level point of view, the ants are dispensable.

ACHILLES: I’m sure no ant would embrace your theory with eagerness.

ANTEATER: Well, I never met an ant with a high-level point of view.

CRAB: What a counterintuitive picture you paint, Dr. Anteater. It seems that, if what you say is true, in order to grasp the whole structure, you have to describe it omitting any mention of its fundamental building blocks.

ANTEATER: Perhaps I can make it a little clearer by an analogy. Imagine you have before you a Charles Dickens novel.

ACHILLES: The Pickwick Papers—will that do?

ANTEATER: Excellently! And now imagine trying the following game: You must find a way of mapping letters onto ideas, so that the entire Pickwick Papers makes sense when you read it letter by letter.

ACHILLES: Hmm.... You mean that every time I hit a word such as “the,” I have to think of three definite concepts, one after another, with no room for variation?

ANTEATER: Exactly. They are the “t”-concept, the “h”-concept, and the “e”-concept—and every time, those concepts are as they were the preceding time.

ACHILLES: Well, it sounds like that would turn the experience of “reading” The Pickwick Papers into an indescribably boring nightmare. It would be an exercise in meaninglessness, no matter what concept I associated with each letter.

ANTEATER: Exactly. There is no natural mapping from the individual letters into the real world. The natural mapping occurs on a higher level-between words, and parts of the real world. If you wanted to describe the book, therefore, you would make no mention of the letter level.

ACHILLES: Of course not! I’d describe the plot and the characters, and so forth.

ANTEATER: So there you are. You would omit all mention of the building blocks, even though the book exists thanks to them. They are the medium, but not the message.

ACHILLES: All right—but what about ant colonies?

ANTEATER: Here, there are active signals instead of passive letters, and active symbols instead of passive words—but the idea carries over.

ACHILLES: Do you mean I couldn’t establish a mapping between signals and things in the real world?

ANTEATER: You would find that you could not do it in such a way that the triggering of new signals would make any sense. Nor could you, succeed on any lower level—for example, the ant level. Only on the symbol level do the triggering patterns make sense. Imagine, for instance, that one day you were watching Aunt Hillary when I arrived to pay a call. You could watch as carefully as you wanted, and yet you would probably perceive nothing more than a rearrangement of ants.

ACHILLES: I’m sure that’s accurate.

ANTEATER: And yet, as I watched, reading the higher level instead of the lower level, I would see several dormant symbols being awakened those which translate into the thought “Oh, here’s that charming D Anteater again—how pleasant!”—or words to that effect.

ACHILLES: That sounds like what happened when the four of us all found different levels to read in the MU-picture-or at least three of us did....

TORTOISE: What an astonishing coincidence that there should be such a resemblance between that strange picture which I chanced upon in the Well-Tempered Clavier and the trend of our conversation.

ACHILLES: Do you think it’s just coincidence?

TORTOISE: Of course.

ANTEATER: Well, I hope you can grasp now how the thoughts in Aunt Hillary emerge from the manipulation of symbols composed of signals composed of teams composed of lower-level teams, all the way down to ants.

ACHILLES: Why do you call it “symbol manipulation”? Who does the manipulating, if the symbols are themselves active? Who is the agent?

ANTEATER: This gets back to the question that you earlier raised about purpose. You’re right that symbols themselves are active, but the activities which they follow are nevertheless not absolutely free. The activities of all symbols are strictly determined by the state of the full system in which they reside. Therefore, the full system is responsible for how its symbols trigger each other, and so it is quite reasonable to speak of the full system as the “agent.” As the symbols operate, the state of the system gets slowly transformed, or updated. But there are many features that remain over time. It is this partially constant, partially varying system that is the agent. One can give a name to the full system. For example, Aunt Hillary is the “who” who can be said to manipulate her symbols; and you are similar, Achilles.

ACHILLES: That’s quite a strange characterization of the notion of who I am. I’m not sure I can fully understand it, but I will give it some thought.

TORTOISE: It would be quite interesting to follow the symbols in your brain as you do that thinking about the symbols in your brain.

ACHILLES: That’s too complicated for me. I have trouble enough just trying to picture how it is possible to look at an ant colony and read it on the symbol level. I can certainly imagine perceiving it at the ant level; and with a little trouble, I can imagine what it must be like to perceive it at the signal level; but what in the world can it be like to perceive an ant colony at the symbol level?

ANTEATER: One learns only through long practice. But when one is at my stage, one reads the top level of an ant colony as easily as you yourself read the “mu” in the MU-picture.

ACHILLES: Really? That must be an amazing experience.

ANTEATER: In a way—but it is also one which is quite familiar to you, Achilles.

ACHILLES: Familiar to me? What do you mean? I have never looked at an ant colony on anything but the ant level.

ANTEATER: Maybe not; but ant colonies are no different from brains in many respects.

ACHILLES: I have never seen nor read any brain either, however.

ANTEATER: What about your own brain? Aren’t you aware of your own thoughts? Isn’t that the essence of consciousness? What else are you doing but reading your own brain directly at the symbol level?

ACHILLES: I never thought of it that way. You mean that I bypass all the lower levels, and see only the topmost level?

ANTEATER: That’s the way it is, with conscious systems. They perceive themselves on the symbol level only, and have no awareness of the lower levels, such as the signal levels.

ACHILLES: Does it follow that in a brain, there are active symbols that are constantly updating themselves so that they reflect the overall state of the brain itself, always on the symbol level?

ANTEATER: Certainly. In any conscious system there are symbols that represent the brain state, and they are themselves part of the very brain state which they symbolize. For consciousness requires a large degree of self-consciousness.

ACHILLES: That is a weird notion. It means that although there is frantic activity occurring in my brain at all times, I am capable of registering that activity in only one way—on the symbol level; and I am completely insensitive to the lower levels. It is like being able to read Dickens novel by direct visual perception, without ever having learned the letters of the alphabet. I can’t imagine anything as weird as that really happening.

CRAB: But precisely that sort of thing did happen when you read “MU”, without perceiving the lower levels “HOLISM” and “REDUCTIONISM”.

ACHILLES: You’re right—I bypassed the lower levels, and saw only the top. I wonder if I’m missing all sorts of meaning on lower levels of my brain as well, by reading only the symbol level. It’s too bad that the top level doesn’t contain all the information about the bottom level, so that by reading the top, one also learns what the bottom level says. But I guess it would be naïve to hope that the top level encodes anything from the bottom level—it probably doesn’t percolate up. The MU-picture is the most striking possible example of that: There, the topmost level says only “MU,” which bears no relation whatever to the lower levels!

CRAB: That’s absolutely true. (Picks up the MU-picture, to inspect it more closely.) Hmm.... There’s something strange about the smallest letters in this picture; they’re very wiggly…

ANTEATER: Let me take a look. (Peers closely at the MU-picture.) I think there’s yet another level, which all of us missed!

TORTOISE: Speak for yourself, Dr. Anteater.

ACHILLES: Oh, no—that can’t be! Let me see. (Looks very carefully.) I know the rest of you won’t believe this, but the message of this picture I staring us all in the face, hidden in its depths. It is simply one word, repeated over and over again, like a mantra—but what an important one: “MU”! What do you know! It is the same as the top level! And none of us suspected it in the least.

CRAB: We would never have noticed it if it hadn’t been for you, Achilles.

ANTEATER: I wonder if the coincidence of the highest and lowest levels happened by chance? Or was it a purposeful act carried out by some creator?

CRAB: How could one ever decide that?

TORTOISE: I don’t see any way to do so, since we have no idea why that particular picture is in the Crab’s edition of the Well-Tempered Clavier.

ANTEATER: Although we have been having a lively discussion, I have still managed to listen with a good fraction of an ear to this very long and complex four-voice fugue. It is extraordinarily beautiful.

TORTOISE: It certainly is. And now, in just a moment, comes an organ point.

ACHILLES: Isn’t an organ point what happens when a piece of music slows down slightly, settles for a moment or two on a single note or chord, and then resumes at normal speed after a short silence?

TORTOISE: No, you’re thinking of a “fermata”—a sort of musical semicolon. Did you notice there was one of those in the prelude?

ACHILLES: I guess I must have missed it.

TORTOISE: Well, you have another chance coming up to hear a fermata—in fact, there are a couple of them coming up, toward the end of this fugue.

ACHILLES: Oh, good. You’ll point them out in advance, won’t you?

TORTOISE: If you like.

ACHILLES: But do tell me, what is an organ point?

TORTOISE: An organ point is the sustaining of a single note by one of the voices in a polyphonic piece (often the lowest voice), while the other voices continue their own independent lines. This organ point is on the note of G. Listen carefully, and you’ll hear it.

ANTEATER: There occurred an incident one day when I visited with Aunt Hillary which reminds me of your suggestion of observing the symbols in Achilles’ brain as they create thoughts which are about themselves.

CRAB: Do tell us about it.

ANTEATER: Aunt Hillary had been feeling very lonely, and was very happy to have someone to talk to that day. So she gratefully told me to help myself to the juiciest ants I could find. (She’s always beets most generous with her ants.)

ACHILLES: Gee!

ANTEATER: It just happened that I had been watching the symbols which were carrying out her thoughts, because in them were some particularly juicy-looking ants.

ACHILLES: Gee!

ANTEATER: So I helped myself to a few of the fattest ants which had been parts of the higher-level symbols which I had been reading. Specifically, the symbols which they were part of were the ones which had expressed the thought “Help yourself to any of the ants which look appetizing.”

ACHILLES: Gee!

ANTEATER: Unfortunately for them, but fortunately for me, the little bugs didn’t have the slightest inkling of what they were collectively telling me, on the symbol level.

ACHILLES: Gee! That is an amazing wraparound. They were completely unconscious of what they were participating in. Their acts could be seen as part of a pattern on a higher level, but of course they were completely unaware of that. Ah, what a pity—a supreme irony, in fact—that they missed it.

CRAB: You are right, Mr. T—that was a lovely organ point.

ANTEATER: I had never heard one before, but that one was so conspicuous that no one could miss it. Very effective.

ACHILLES: What? Has the organ point already occurred? How can I not have noticed it, if it was so blatant?

TORTOISE: Perhaps you were so wrapped up in what you were saying that you were completely unaware of it. Ah, what a pity—a supreme irony, in fact—that you missed it.

CRAB: Tell me, does Aunt Hillary live in an anthill?

ANTEATER: Well, she owns a rather large piece of property. It used to belong to someone else, but that is rather a sad story. In any case, her estate is quite expansive. She lives rather sumptuously, compared to many other colonies.

ACHILLES: How does that jibe with the communistic nature of ant colonies which you earlier described to us? It sounds quite inconsistent, to me, to preach communism and to live in a fancy estate!

ANTEATER: The communism is on the ant level. In an ant colony all ants work for the common good, even to their own individual detriment at times. Now this is simply a built-in aspect of Aunt Hillary’s structure, but for all I know, she may not even be aware of this internal communism. Most human beings are not aware of anything about their neurons; in fact they probably are quite content not to know anything about their brains, being somewhat squeamish creatures. Aunt Hillary is also somewhat squeamish; she gets rather antsy whenever she starts to think about ants at all. So she avoids thinking about them whenever possible. I truly doubt that she knows anything about the communistic society which is built into her very structure. She herself is a staunch believer in libertarianism—you know, laissez faire and all that. So it makes perfect sense, to me at least, that she should live in a rather sumptuous manor.

ILLUSTRATION BY THE AUTHOR.

TORTOISE: As I turned the page just now, while following along in this lovely edition of the Well-Tempered Clavier, I noticed that the first of the two fermatas is coming up soon—so you might listen for it, Achilles.

ACHILLES: I will, I will.

TORTOISE: Also, there’s a most curious picture facing this page.

CRAB: Another one? What next?

TORTOISE: See for yourself. (Passes the score over to the Crab.)

CRAB: Aha! It’s just a few bunches of letters. Let’s see—there are various numbers of the letters “J,” “S,” “B,” “m,” “a,” and “t.” It’s strange, how the first three letters grow, and then the last three letters shrink again.

ANTEATER: May I see it?

CRAB: Why, certainly.

ANTEATER: Oh, by concentrating on details, you have utterly missed the big picture. In reality, this group of letters is “f,” “e,” “r,” “A,” “C,” “H,” without any repetitions. First they get smaller, then they get bigger.. Here, Achilles—what do you make of it?

ACHILLES: Let me see. Hmm. Well, I see it as a set of uppercase letters which grow as you move to the right.

TORTOISE: Do they spell anything?

ACHILLES: Ah… “J. S. BACH.” Oh! I understand now. It’s Bach’s name!

TORTOISE: Strange that you should see it that way. I see it as a set of lower-case letters, shrinking as they move to the right, and… spelling out… the name of… (Slows down slightly, especially drawing out the last few words. Then there is a brief silence. Suddenly he resumes as if nothing unusual had happened.) — “fermat.”

ACHILLES: Oh, you’ve got Fermat on the brain, I do believe. You see Fermat’s Last Theorem everywhere.

ANTEATER: You were right, Mr. Tortoise—I just heard a charming little fermata in the fugue.

CRAB: So did I.

ACHILLES: Do you mean everybody heard it but me? I’m beginning to feel stupid.

TORTOISE: There, there, Achilles—don’t feel bad. I’m sure you won t miss Fugue’s Last Fermata (which is coming up quite soon). But, to return to our previous topic, Dr. Anteater, what is the very sad story which you alluded to, concerning the former owner of Aunt Hillary’s property?

ANTEATER: The former owner was an extraordinary individual, one of the most creative ant colonies who ever lived. His name was Johant Sebastiant Fermant, and he was a mathematiciant by vocation, but a musiciant by avocation.

ACHILLES: How very versatile of him!

ANTEATER: At the height of his creative powers, he met with a most untimely demise. One day, a very hot summer day, he was out soaking up the warmth, when a freak thundershower—the kind that hits only once every hundred years or so—appeared from out of the blue and thoroughly drenched J. S. F. Since the storm came utterly without warning, the ants got completely disoriented and confused. The intricate organization that had been so finely built up over decades all went down the drain in a matter of minutes. It was tragic.

ACHILLES: Do you mean that all the ants drowned, which obvious would spell the end of poor J. S. F.?

ANTEATER. Actually, no. The ants managed to survive, every last one them, by crawling onto various sticks and logs that floated above the raging torrents. But when the waters receded and left the ants back on their home grounds, there was no organization left. The caste distribution was utterly destroyed, and the ants themselves had no ability to reconstruct what had once before been such a finely tune organization. They were as helpless as the pieces of Humpty Dumpty in putting themselves back together again. I myself tried, like all the king’s horses and all the king’s men, to put poor Fermant together again. I faithfully put out sugar and cheese, hoping against hope that somehow Fermant would reappear… (Pulls out a handkerchief and wipes his eyes.)

ACHILLES: How valiant of you! I never knew Anteaters had such big hearts.

ANTEATER: But it was all to no avail. He was gone, beyond reconstitution. However, something very strange then began to take place, over the next few months, the ants that had been components of J.S.F. slowly regrouped, and built up a new organization. And thus was Aunt Hillary born.

CRAB: Remarkable! Aunt Hillary is composed of the very same ants Fermant was?

ANTEATER: Well, originally she was, yes. By now, some of the older an have died, and been replaced. But there are still many holdover from the J.S.F.-days.

CRAB: And can’t you recognize some of J.S.F.’s old traits coming to the fore, from time to time, in Aunt Hillary?

ANTEATER: Not a one. They have nothing in common. And there is no reason they should, as I see it. There are, after all, often sever distinct ways to rearrange a group of parts to form a “sum.” An Aunt Hillary was just a new “sum” of the old parts. Not more than the sum, mind you just that particular kind of sum.

TORTOISE: Speaking of sums, I am reminded of number theory, where occasionally, one will be able to take apart a theorem into its component symbols, rearrange them in a new order, and come up with a new theorem.

ANTEATER: I’ve never heard of such a phenomenon, although I confess to being a total ignoramus in the field.

ACHILLES: Nor have I heard of it—and I am rather well versed in the field, if I don’t say so myself. I suspect Mr. T is just setting up one of his elaborate spoofs. I know him pretty well by now.

ANTEATER: Speaking of number theory, I am reminded of J. S. F. again, for number theory is one of the domains in which he excelled. In fact he made some rather remarkable contributions to number theory Aunt Hillary, on the other hand, is remarkably dull-witted in any thing that has even the remotest connection with mathematics. Also, she has only a rather banal taste in music, whereas Sebastiant was extremely gifted in music.

ACHILLES: I am very fond of number theory. Could you possibly relate to us something of the nature of Sebastiant’s contributions?

ANTEATER: Very well, then. (Pauses for a moment to sip his tea, then resumes.) Have you heard of Fourmi’s infamous “Well-Tested Conjecture”?

ACHILLES: I’m not sure.... It sounds strangely familiar, and yet I can quite place it.

ANTEATER: It’s a very simple idea. Lierre de Fourmi, a mathematiciant by vocation but lawyer by avocation, had been reading in his copy of the classic text Arithmetica by Di of Antus, and came across a page containing the equation

He immediately realized that this equation has infinitely many solutions a, b, c, and then wrote in the margin the following notorious comment:

Ever since that year, some three hundred days ago, mathematiciants have been vainly trying to do one of two things: either to prove Fourmi’s claim, and thereby vindicate Fourmi’s reputation, which, although very high, has been somewhat tarnished by skeptics who think he never really found the proof he claimed to have found—or else to refute the claim, by finding a counterexample: a set of four integers a, b, c, and n, with n > 2, which satisfy the equation. Until very recently, every attempt in either direction had met with failure. To be sure, the Conjecture has been verified for many specific values of n—in particular, all n up to 125,000. But no one had succeeded in proving it for all n—no one, that is, until Johant Sebastiant Fermant came upon the scene. It was he who found the proof that cleared Fourmi’s name. It now goes under the name “Johant Sebastiant’s Well-Tested Conjecture.”

During emigrations army ants sometimes create bridges of their own bodies. In this photograph of such a bridge (de Fourmi Lierre), the workers Ecilon burchelli colony can be seen linking their legs and, along the top of the bridge, hooking their tarsal claws together to form irregular systems of chains. A symbiotic silverfish, Trichatelura manni, is seen crossing the bridge in the center. (From E. O. Wilson, The Insect Societies. Photograph courtesy of C. W. Rettenmeyer.)

ACHILLES: Shouldn’t it be called a “Theorem” rather than a “Conjecture,” if it’s finally been given a proper proof?

ANTEATER: Strictly speaking, you’re right, but tradition has kept it this way.

TORTOISE: What sort of music did Sebastiant do?

ANTEATER: He had great gifts for composition. Unfortunately, his greatest work is shrouded in mystery, for he never reached the point of publishing it. Some believe that he had it all in his mind; others are more unkind, saying that he probably never worked it out at all, but merely blustered about it.

ACHILLES: What was the nature of this magnum opus?

ANTEATER: It was to be a giant prelude and fugue; the fugue was to have twenty-four voices, and to involve twenty-four distinct subjects, one in each of the major and minor keys.

ACHILLES: It would certainly be hard to listen to a twenty-four-voice fugue as a whole!

CRAB: Not to mention composing one!

ANTEATER: But all that we know of it is Sebastiant’s description of it, which he wrote in the margin of his copy of Buxtehude’s Preludes and Fugues for Organ. The last words which he wrote before his tragic demise were:

And the unrealized masterpiece simply goes by the name “Fermant’s Last Fugue.”

ACHILLES: Oh, that is unbearably tragic.

TORTOISE: Speaking of fugues, this fugue that we have been listening to is nearly over. Toward the end, there occurs a strange new twist on its theme. (Flips the page in the Well-Tempered Clavier.) Well, what have we here? A new illustration-how appealing! (Shows it to the Crab.)

CRAB: Well, what have we here? Oh, I see: it’s “HOLISMIONISM,” written in large letters that first shrink and then grow back to their original size. But that doesn’t make any sense, because it’s not a word. Oh me, oh my! (Passes it to the Anteater.)

ANTEATER: Well, what have we here? Oh, I see: it’s “REDUCTHOLISM,” written in small letters that first grow and then shrink back to their original size. But that doesn’t make any sense, because it’s not a word. Oh my, oh me! (Passes it to Achilles.)

ACHILLES: I know the rest of you won’t believe this, but in fact this picture consists of the word “HOLISM” written twice, with the letters continually shrinking as they proceed from left to right. (Returns it to the Tortoise.)

ILLUSTRATION BY THE AUTHOR.

TORTOISE: I know the rest of you won’t believe this, but in fact this picture consists of the word “REDUCTIONISM” written once, with the letters continually growing as they proceed from left to right.

ACHILLES: At last—I heard the new twist on the theme this time! I am so glad that you pointed it out to me, Mr. Tortoise. Finally, I think I am beginning to grasp the art of listening to fugues..

Reflections

Is a soul greater than the hum of its parts? The participants in the preceding dialogue seem to have divergent views on this question. What is certain and agreed upon, however, is that the collective behavior of a system of individuals can have many surprising properties.

Many people, on reading this dialogue, are reminded of the seemingly purposive, selfish, survival-oriented behavior of countries that emerges somehow from the habits and institutions of their citizens: their educational system, legal structure, religions, resources, style of consumption and level of expectations, and so on. When a tight organization forms from distinct individuals—particularly when contributions to the organization are not traceable to specific individuals in the lower level we tend to see it as a higher-level individual and often speak of it in anthropomorphic terms. A newspaper article about a terrorist group described it as “playing its cards extremely close to its chest.” It is often said of Russia that it “desires” world recognition of its might because it “suffers” from a “long-standing inferiority complex” with respect to Western Europe. While admittedly metaphors, these examples serve to demonstrate how strong the urge is to personify organizations.

The component individuals of organizations—secretaries, workers, bus drivers, executives, and so on—have their own goals in life, which, one might expect, would come into conflict with any higher-level entity of which they formed a part, but there is an effect (which many students of political science would regard as insidious and sinister) whereby the organization co-opts and exploits these very goals, taking advantage of the individuals’ pride, need for self-esteem, and so on, and turning them, back to its own profits. There emerges from all the many low-level goals a kind of higher-level momentum that subsumes all of them, that sweeps them along and thereby perpetuates itself.

Therefore it is perhaps not so silly for the Tortoise to object to Achilles’ comparison of himself to an ant and to prefer an attempt by Achilles to “map himself,” at a suitable level, onto an ant colony. Similarly, we may sometimes wonder to ourselves “What is it like to be China? How different from that would it feel to be the United States?” Do such questions makes any kind of sense at all? We shall postpone detailed discussion of them until after Nagel’s piece on bats (selection 24). Nonetheless, let us think a bit right now about whether it makes sense to think of “being” a country. Does a country have thoughts or beliefs? It all comes down to whether a country has a symbol level, in the sense that Aunt Hillary does. Instead of saying that a system “has a symbol level,” we might instead say, “It is a representational system.”

This concept of “representational system” is a crucial one in this book, and needs a somewhat precise definition. By “representational system” we will mean an active, self-updating collection of structures organized to “mirror” the world as it evolves. A painting, no matter how representational, would thus be excluded, since it is static. Curiously, we mean also to exclude mirrors themselves, although the argument could be made that the set of images in a mirror keeps quite up to date with the world! The lack in this case is twofold. First, the mirror itself does not make any distinction between images of different objects—it mirrors the universe, but sees no categories. In fact, a mirror makes only one image it is in the eye of the beholder that the mirror’s single image breaks up into “separate” images of many distinct objects. A mirror cannot be said to perceive—only to reflect. Second, the image in a mirror is not an autonomous structure with its own “life”; it depends directly on the external world. If the lights are turned off, it goes away. A representational system should be able to keep on going even if cut off from contact with the reality it is “reflecting”—although you now see that “reflection” is not quite a rich enough metaphor. The isolated representational structures should now continue to evolve in a way that reflects, if not the true way the world will evolve, at least a probable way. Actually, a good representational system will sprout parallel branches for various possibilities that can be reasonably anticipated. Its internal models will, in the metaphorical sense defined in the Reflections on “Rediscovering the Mind,” go into superpositions of states, each with an associated subjective estimate of likelihood.

In brief, then, a representational system is built on categories; it sifts incoming data into those categories, when necessary refining or enlarging its network of internal categories; its representations or “symbols” interact among themselves according to their own internal logic; this logic, although it runs without ever consulting the external world, nevertheless creates a faithful enough model of the way the world works that it manages to keep the symbols pretty much “in phase” with the world they are supposed to be mirroring. A television is thus not a representational system, as it indiscriminately throws dots onto its screen without regard to what kinds of things they represent, and the patterns on the screen do not have autonomy—they are just passive copies of things “out there.” By contrast, a computer program that can “look” at a scene and tell you what is in that scene comes closer to being a representational system. The most advanced artificial intelligence work on computer vision hasn’t yet cracked that nut. A program that could look at a scene and tell you not only what kinds of things are in the scene, but also what probably caused that scene and what will probably ensue in it—that is what we mean by a representational system. In this sense, is a country a representational system? Does a country have a symbol level? We’ll leave this one for you to ponder on.

One of the crucial notions of the Ant Fugue is the “caste distribution” or “state,” for it is claimed that that is a causal agent in determining the future of the organism. Yet this seems to contradict the idea that all of a system’s behavior comes from underlying laws—those of ants of neurons, in the case of colonies or brains—but ultimately, in either case those of particles. Is there such a thing as “downward causality” put starkly, the notion that “a thought can influence the path of an electron”?

In Inside the Brain by William Calvin and George Ojemann, there is a provocative series of questions asked about a neural firing. “What starts it?” they ask. What causes the sodium channels to open up? (The function of the sodium channels is to let sodium ions into the neuron, and when their concentration is high enough, that then triggers the release of the neurotransmitters, whose flow from one neuron to another constitutes the essence of neural firing.) The answer is, the sodium channels are voltage-sensitive, and they have just been hit by a strong enough voltage pulse to flip their state from closed to open.

“But what causes the voltage to rise originally, so that it crosses this threshold … and sets off this sequence of events called the impulse?” they go on. The answer is, various “nodes” along the neuron’s axon have simply relayed this high voltage from one station to the next. So then the question is again transformed. This time they ask, “But what causes the very first impulse to occur at the very first node? Where does that voltage shift come from? What precedes the impulse?”

Well, for most neurons inside the brain—“interneurons,” meaning neurons that are fed into not by sensory input but only by other neurons—the answer is, their first node’s voltage shift is provoked by the total effect of the pulses of neurotransmitters coming in from other neurons. (We could call those neurons “upstream” neurons, but that would imply, quite falsely, that the flow of neural activity in the brain follows a line in only one direction, in the manner of a river. In fact, as a rule, neural flow patterns are far from linear and make loops all over the place, quite unlike rivers.)

Thus we seem to get into a vicious circle—a chicken-and-egg type of riddle. Question: “What triggers a neural firing?” Answer: “Other neural firings!” But the real question remains unanswered: “Why those neurons, and not others? Why this vicious circle and not another neural loop in another part of the brain?” To answer this, we have to shift levels and talk about the relationship of the brain to the ideas it encodes, which then would require us to talk about how the brain encodes, or represents, its concepts about the world. Since we do not wish to theorize in this book on the details of such matters, we will talk about a related but simpler concept.

Imagine an intricately bifurcating and rejoining domino-chain network. Suppose that each domino has a little time-delayed spring underneath it that stands it up again five seconds after it has fallen. By setting up the network in various configurations, one could actually program the system of dominoes to perform calculations with numbers, exactly as one could a full-scale computer. Various pathways would carry out various parts of the calculation, and elaborate branching loops could be set up. (Note how this image is not too different, then, from that of networks of neurons in a brain.)

One could imagine a “program” trying to break the integer 641 into the product of its prime factors. “Why isn’t this particular domino ever falling down?” you might ask, pointing at one that you’ve been watching for a long time. An answer on one level would be “Because its predecessor never falls.” But that low-level “explanation” only begs the question, What one really wants—the only satisfying answer, in fact—is an answer on the level of the concepts of the program: “It never falls because it is in a stretch of dominoes that gets activated only when a divisor is found. But 641 has no divisors—it is prime. So the reason that domino never falls has nothing to do with physics or domino chains—it is simply the fact that 641 is prime.”

But have we then admitted that higher-level laws actually are responsible, and govern the system above and beyond lower-level laws? No. It is simply that an explanation that makes any sense demands higher-level concepts. The dominos certainly don’t know they are part of a program nor do they need to—any more than the keys of a piano know, or need to know, which piece you are playing. Think how strange it would be if they did! Nor do your neurons know that they are involved in thinking these thoughts right now, nor ants that they are part of the grand scheme of their colony.

There is a further-back question that might arise in your mind “What laws, at what level, are responsible for the existence of the program and the domino chains—indeed, for the manufacturing of the dominoes at all?” To answer this and the many questions it inevitably triggers we are sent sailing backward in time over larger and larger spans, back into all the reasons our society exists, back to the origin of life, and so on. It is more convenient to sweep these many questions under the rug and simply to leave our reason as: the primeness of 641. We prefer this kind of compact higher-level explanation, one that eliminates long view into the past and that concentrates on the present or the timeless. But if we want to trace events to their ultimate causes, we are forced into reductionistic views as described by Dawkins or the Tortoise. Indeed ultimately we are sent back to the physicists, who will refer us to the “Bi Bang” as the primordial cause of everything. This is not satisfying, how ever, because we want an answer at a level that appeals to concept familiar to people—and, fortunately, nature is stratified enough that this is often possible.

We asked whether a thought can influence the course of an electron in flight. The reader could easily conjure up an image we do not have in mind—namely, of a deeply concentrating “psychic” with furrowed brow beaming his “waves of Plutonian energy” (or whatever he calls them) outwards toward an object—say a tumbling die—and influencing the way it will land. We do not believe in anything of the sort. We do not believe that there is some as yet undiscovered “mental magnetism” through which concepts could “reach down” and, through some sort of “semantic potential,” alter the paths of particles, making them deviate from what present-day physics would predict. We are talking about something else. It is more a question of where explanatory power comes from—perhaps a question of the proper ways of using words, a question of how to reconcile everyday usage of terms like “cause” with the scientific usage of those terms. Thus, is it reasonable to explain the trajectories of particles by making references to higher-level notions such as “beliefs,” “desires,” and so forth? The reader may detect that we see much utility in adopting this way of speaking. Just as evolutionary biologists feel free to use “teleological shorthand” to condense their concepts down to an intuitively reasonable size, so we feel that people who study the mechanisms of thought must necessarily become conversant with ways of translating back and forth between purely reductionistic language and a sort of “holistic” language in which wholes do indeed exert a visible effect on their parts, do indeed possess “downward causality.”

In physics, when a shift of point of view is made, sometimes the laws may appear to be different. Think of the amusement park ride in which people line the inner walls of a large cylinder. The cylinder starts spinning and as it does so, its floor falls away, as if a giant can opener had just opened this can from below. The people are left hanging, with their backs powerfully pressed against the wall by the so-called centrifugal force. If you were on this ride and attempted to throw a tennis ball to a friend directly across the cylinder, you would see the ball flying crazily off course, perhaps even boomeranglike returning to you! Of course, this is simply because you would move around in the same amount of time as the ball sailed (in a straight line) across the cylinder. But if you were unaware that you were in a rotating frame, you might invent a name for the strange deflecting force that makes your ball veer away from its intended destination. You might think it was some bizarre variation of gravity. This would be strongly supported by the observation that this force acted identically on any two objects with the same mass, as gravity does. Amazingly enough, this simple observation—that “fictitious forces” and gravity are easily confused—is at the heart of Einstein’s great theory of general relativity. The point of this example is that a shift of frame of reference can induce a shift of perceptions and concepts—a shift in ways of perceiving causes and effects. If it is good enough for Einstein, it ought to be good enough for us!

We will not belabor the reader further with descriptions of the tricky shifts of point of view as one swings back and forth between the level of wholes and the level of their parts. We will simply introduce some catchy terminology which may titillate the reader into thinking further about these issues. We have contrasted “reductionism” and “holism.” Now you can see that “reductionism” is synonymous with “upward causality” and “holism” with “downward causality.” These are concepts having to do with how events on different size-scales in space determine each other. They have counterpart notions in the time dimension: to reductionism corresponds the idea of predicting the future from the past without regard to “goals” of organisms; to holism corresponds the idea that only inanimate objects can be so predicted, but that in the case of animate objects, purposes and goals and desires and so on are essential to explain their actions. This view, often called “goal-oriented” or “teleological,” could equally well be termed “goalism”—and its opposite could be termed “predictionism.” Thus predictionism emerges as the temporal counterpart to reductionism, with goalism being the temporal counterpart to holism. Predictionism is the doctrine that only “upstream” events—and nothing “downstream”—need be taken into account in determining the way the present flows into the future. Goalism, its opposite, sees animate objects as moving toward goals in the future—thus it sees future events in some sense projecting causal power backward in time, or retroactively. We can call this “retroactive causality”; it is the temporal counterpart to holism’s “introactive causality,” where causes are seen to flow “inward” (from wholes to their parts). Put goalism and holism together, and you have—you guessed it—soulism! Put predictionism and reductionism together, and you get—mechanism.

To summarize, we can draw a little chart:

Hard scientists // Soft scientists

Reductionism // Holism

(upward causality) // (downward causality)

+ // +

Predictionism // Goalism

(upstream causality) // (downstream causality)

= Mechanism // = Soulism

Well, now that we have indulged our fancy for wordplay, let us move on. A fresh perspective is offered us by another metaphor for brain activity: that of the “thinking wind chime.” Think of a complex wind chime structured like a mobile, with glass “tinklers” dangling like leaves off branches, branches dangling from larger branches, and so on. When wind strikes the chime, many tinklers flutter and slowly the whole structure changes on all levels. It is obvious that not just the wind, but also the chime state, determines how the little glass tinklers move. Even if only one single glass tinkler were dangling, the twistedness of its string would have as much to do with how the chime would move as the wind would.

Just as people do things “of their own volition,” so the chime seems to have a “will of its own.” What is volition? A complicated internal configuration, established through a long history, that encodes tendencies toward certain future internal configurations and away from others. This is present in the lowliest wind chime.

But is this fair? Does a wind chime have desires? Can a wind chime think? Let’s fantasize a bit, adding many features to our chime. Suppose there is a fan on a track near the chime, whose position is electronically controlled by the angle of one particular branch in the chime, and whose blades’ rotational speed is controlled by the angle of another branch. Now the chime has some control over its environment, like having big hands that are guided by groups of tiny, insignificant-seeming neurons: the chime plays a larger role in determining its own future.

Let’s go further and suppose that many of the branches control blowers, one blower per branch. Now when wind—natural or blower caused—blows, a group of tinklers will shimmer, and subtly and delicately they will transmit a soft shimmer to various other portions of the chime. That in turn propagates around, gradually twisting branches, thus creating a new chime state that determines where the blowers point and how hard they blow, and this will set up more responses in the chime. Now the external wind and the internal chime state are intertwined in a very complicated way—so complicated, in fact, that it would be very hard to disentangle them conceptually from each other.

Imagine two chimes in the same room, each affecting the other by blowing small gusts of wind in the direction of the other. Who can say that it makes sense to decompose the system into two natural parts? It might be that the best way to look at the system is in terms of top-level branches, in which case there might be five or ten natural parts in each of the two chimes—or perhaps the branches a level below that are the best units to look at, in which case we might see twenty or more per chime.... It is all a matter of convenience. All parts interact in some sense with all others, but there might be two parts that are somewhat discernible as separate in space or in coherence of organization—certain types of shimmering might stay localized in one region, for instance—and we could then speak of distinct “organisms.” But note how the whole thing is still explicable in terms of physics.

We could now posit a mechanical hand whose motions are controlled by the angles of, say, two dozen high-level branches. These branches are of course intimately tied in with the entire chime state. We could imagine the chime state determining the hand’s motions in a curious way—namely telling the hand which chess piece to pick up and move on a board. Wouldn’t it be a marvelous coincidence if it always picked up a sensible piece and made a legal move? And an even more marvelous coincidence if its moves were always good moves? Hardly. If this were to happen, it would be precisely because it was not a coincidence. It would be because the chime’s internal state had representational power.

Once again we’ll back away from trying to describe precisely how ideas could be stored in this strange shimmering structure, reminiscent of a quaking aspen. The point has been to suggest to the reader the potential delicacy, intricacy, and self-involvedness of a system that responds to external stimuli and to features at various levels of its own internal configuration.

It is well-nigh impossible to disentangle such a system’s response to the outside world from its own self-involved response, for the tiniest external perturbation will trigger a myriad tiny interconnected events, and a cascade will ensue. If you think of this as the system’s “perception” of input, then clearly its own state is also “perceived” in a similar way. Self-perception cannot be disentangled from perception.

The existence of a higher-level way of looking at such a system is not a foregone conclusion; that is, there is no guarantee that we could decode the chime state into a consistent set of English sentences expressing the beliefs of the system, including, for instance, the set of rules of chess (as well as how to play a good game of chess!). However, when systems like that have evolved by means of natural selection, there will be a reason that some have survived and most others failed to: meaningful internal organization allowing the system to take advantage of its environment and to control it, at least partially.

In the wind chime, the hypothetical conscious ant colony, and the brain, that organization is stratified. The levels in the wind chime corresponded to the different levels of branches dangling from other branches, with the spatial disposition of the highest branches representing the most compact and abstract summary of the global qualities of the chime state, and the disposition of the many thousands (or millions?) of quivering individual tinklers giving a totally unsummarized, unintuitive, but concrete and local description of the chime state. In the ant colony, there were ants, teams, signals at various levels, and finally the caste distribution or “colony state”—again the most incisive yet abstract view of the colony. As Achilles marveled, it is so abstract that the ants themselves are never mentioned! In the brain, we just do not know how to find the high-level structures that would provide a readout in English of the beliefs stored in the brain. Or rather, we do—we just ask the brain’s owner to tell us what he or she believes! But we have no way of physically determining where or how beliefs are coded.[16]

In our three systems, various semiautonomous subsystems exist, each of which represents a concept, and various input stimuli can awaken certain concepts, or symbols. Note that in this view there is no “inner eye” that watches all the activity and “feels” the system; instead the system’s state itself represents the feelings. The legendary “little person” who would play that role would have to have yet a smaller “inner eye,” after all, and that would lead to further little people and ever-tinier “inner eyes”—in short, to infinite regress of the worst and silliest kind. In this kind of system, contrariwise, the self-awareness comes from the system’s intricately intertwined responses to both external and internal stimuli. This kind of pattern illustrates a general thesis: “Mind is a pattern perceived by a mind.” This is perhaps circular, but it is neither vicious nor paradoxical.

The closest one could come to having a “little person” or an “inner eye” that perceives the brain’s activity would be in the self-symbol—a complex subsystem that is a model of the full system. But the self-symbol does not perceive by having its own repertoire of smaller symbols (including its own self-symbol—an obvious invitation to infinite regress). Rather, the self-symbol’s joint activation with ordinary (nonreflexive) symbols constitutes the system’s perception. Perception resides at the level of the full system, not at the level of the self-symbol. If you want to say that the self-symbol perceives something, it is only in the sense that a male moth perceives a female moth, or in the sense that your brain perceives your heart rate—at a level of microscopic intercellular chemical messages.

The last point to be made here is that the brain needs this multileveled structure because its mechanisms must be extraordinarily flexible in order to cope with an unpredictable, dynamic world. Rigid programs will go extinct rapidly. A strategy exclusively for hunting dinosaurs will be no good when it comes to hunting woolly mammoths, and much less good when it comes to tending domestic animals or commuting to work on the subway. An intelligent system must be able to reconfigure itself—to sit back, assess the situation, and regroup—in rather deep ways; such flexibility requires only the most abstract kinds of mechanisms to remain unchanged. A many-layered system can have programs tailored to very specific needs (e.g., programs for chess playing, woolly-mammoth hunting, and so on) at its most superficial level, and progressively more abstract programs at deeper layers, thus getting the best of both worlds. Examples of the deeper type of program would be ones for recognizing patterns; for evaluating conflicting pieces of evidence; for deciding which, among rival subsystems clamoring for attention, should get higher priority; for deciding how to label the currently perceived situation for possible retrieval on future occasions that may be similar; for deciding whether two concepts really are or are not analogous; and so on.

Further description of this kind of system would carry us deep into the philosophical and technical territory of cognitive science, and we will not go that far. Instead, we refer readers to the “Further Readings” section for discussions of the strategies of knowledge representation it humans and in programs. In particular, Aaron Sloman’s book The Computer Revolution in Philosophy goes into great detail on these issues.

D.R.H

12 Arnold Zuboff The Story of a Brain

Once upon a time, a kind young man who enjoyed many friends and great wealth learned that a horrible rot was overtaking all of his body but his nervous system. He loved life; he loved having experiences. Therefore he was intensely interested when scientist friends of amazing abilities proposed the following:

“We shall take the brain from your poor rotting body and keep it healthy in a special nutrient bath. We shall have it connected to a machine that is capable of inducing in it any pattern at all of neural firings and is therein capable of bringing about for you any sort of total experience that it is possible for the activity of your nervous system to cause or to be.”

The reason for this last disjunction of the verbs to cause and to be was that, although all these scientists were convinced of a general theory that they called “the neural theory of experience,” they disagreed on the specific formulation of this theory, they all knew of countless instances in which it was just obvious that the state of the brain, the pattern of its activity, somehow had made for a man’s experiencing this rather than that. It seemed reasonable to them all that ultimately what decisively controlled any particular experience of a man-controlled whether it existed and what it was like—was the state of his nervous system and more specifically that of those areas of the brain that careful research had discovered to be involved in the various aspects of consciousness. This conviction was what had prompted their proposal to their young friend. That they disagreed about whether an experience simply consisted in or else was caused by neural activity was irrelevant to their belief that as long as their friend’s brain was alive and functioning under their control, they could keep him having his beloved experience indefinitely, just as though he were walking about and getting himself into the various situations that would in a more natural way have stimulated each of those patterns of neural firings that they would bring about artificially. If he were actually to have gazed through a hole in a snow-covered frozen pond, for instance, the physical reality there would have caused him to experience what Thoreau described: “the quiet parlor of the fishes, pervaded by a softened light as through a window of ground glass, with its bright sanded floor the same as in summer.” The brain lying in its bath, stripped of its body and far from the pond, if it were made to behave precisely as it naturally would under such pond-hole circumstances, would have for the young man that very same experience.

Well, the young man agreed with the concept and looked forward to its execution. And a mere month after he had first heard the thing proposed to him, his brain was floating in the warm nutrient bath. His scientist friends kept busy researching, by means of paid subjects, which patterns of neuron firings were like the natural neural responses to very pleasant situations; and, through the use of a complex electrode machine, they kept inducing only these neural activities in their dear friend’s brain.

Then there was trouble. One night the watchman had been drinking, and, tipsily wandering into the room where the bath lay, he careened forward so his right arm entered the bath and actually split the poor brain into its two hemispheres.

The brain’s scientist friends were very upset the next morning. They had been all ready to feed into the brain a marvelous new batch of experiences whose neural patterns they had just recently discovered.

“If we let our friend’s brain mend after bringing the parted hemispheres together,” said Fred, “we must wait a good two months before it will be healed well enough so that we can get the fun of feeding him these new experiences. Of course, he won’t know about the waiting; but we sure will! And unfortunately, as we all know, two separated halves of a brain can’t entertain the same neural patterns that they can when they’re together. For all those impulses which cross from one hemisphere to another during a whole-brain experience just can’t make it across the gap that has been opened between them.”

The end of this speech gave someone else an idea. Why not do the following? Develop tiny electrochemical wires whose ends could be fitted to the synapses of neurons to receive or discharge their neural impulses. These wires could then be strung from each neuron whose connection had been broken in the split to that neuron of the other hemisphere to which it had formerly been connected. “In this way,” finished Bert, the proposer of this idea, “all those impulses that were supposed to cross over from one hemisphere to the other could do just that—carried over the wires.”

This suggestion was greeted with enthusiasm, since the construction of the wire system, it was felt, could easily be completed within a week. But one grave fellow named Cassander had worries. “We all agree that our friend has been having the experiences we’ve tried to give him. That is, we all accept in some form or other the neural theory of experience. Now, according to this theory as we all accept it, it is quite permissible to alter as one likes the context of a functioning brain, just so long as one maintains the pattern of its activity. We might look at what we’re saying this way. There are various conditions that make for the usual having of an experience—an experience, for instance, like that pond-hole experience we believe we gave our friend three weeks ago. Usually these conditions are the brain being in an actual body on an actual pond stimulated to such neural activity as we did indeed give our friend. We gave our friend the neural activity without those other conditions of its context because our friend has no body and because we believe that what is essential and decisive for the existence and character of an experience anyway is not such context but rather only the neural activity that it can stimulate. The contextual conditions, we believe, are truly inessential to the bare fact of a man having an experience—even if they are essential conditions in the normal having of that experience. If one has the wherewithal, as we do, to get around the normal necessity of these external conditions of an experience of a pond hole, then such conditions are no longer necessary. And this demonstrates that within our concept of experience they never were necessary in principle to the bare fact of having the experience.

“Now, what you men are proposing to do with these wires amounts to regarding as inessential just one more normal condition of our friend’s having his experience. That is, you are saying something like what I just said about the context of neural activity—but you’re saying it about the condition of the proximity of the hemispheres of the brain to one another. You’re saying that the two hemispheres being attached to one another in the whole-brain experiences may be necessary to the coming about of those experiences in the usual case, but if one can get around a breach of this proximity in some, indeed, unusual case, as you fellows would with your wires, there’d still be brought about just the same bare fact of the same experience being had! You’re saying that proximity isn’t a necessary condition to this bare fact of an experience. But isn’t it possible that even reproducing precisely the whole-brain neural patterns in a sundered brain would, to the contrary, not constitute the bringing about of the whole-brain experience? Couldn’t proximity be not just something to get around in creating a particular whole-brain experience but somehow an absolute condition and principle of the having of a whole-brain experience?”

Cassander got little sympathy for his worries. Typical replies ran something like this: “Would the damn hemispheres know they were connected by wires instead of attached in the usual way? That is, would the fact get encoded in any of the brain structures responsible for speech, thought or any other feature of awareness? How could this fact about how his brain looks to external observers concern our dear friend in his pleasures at all—any more than being a naked brain sitting in a warm nutrient bath does? As long as the neural activity in the hemispheres—together or apart—matches precisely that which would have been the activity in the hemispheres lumped together in the head of a person walking around having fun, then the person himself is having that fun. Why, if we hooked up a mouth to these brain parts, he’d be telling us through it about his fun.” In reply to such answers, which were getting shorter and angrier, Cassander could only mutter about the possible disruption of some experiential field “or some such.”

But after the men had been working on the wires for a while someone else came up with an objection to their project that did stop them. He pointed out that it took practically no time for an impulse from one hemisphere to enter into the other when a brain was together and functioning normally. But the travel of these impulses over wires must impose a tiny increase on the time taken in such crossovers. Since the impulses in the rest of the brain in each hemisphere would be taking their normal time, wouldn’t the overall pattern get garbled, operating as if there were a slowdown in only one region? Certainly it would be impossible to get precisely the normal sort of pattern going—you’d have something strange, disturbed.

When this successful objection was raised, a man with very little training in physics suggested that somehow the wire be replaced by radio signals. This could be done by outfitting the raw face—of the split—of each hemisphere with an “impulse cartridge” that would be capable of sending any pattern of impulses into the hitherto exposed and unconnected neurons of that hemisphere, as well as of receiving from those neurons any pattern of impulses that that hemisphere might be trying to communicate to the other hemisphere. Then each cartridge could be plugged into a special radio transmitter and receiver. When a cartridge received an impulse from a neuron in one hemisphere intended for a neuron of the other, the impulse could then be radioed over and properly administered by the other cartridge. The fellow who suggested this even mused that then each half of the brain could be kept in a separate bath and yet the whole still be engaged in a single whole-brain experience.

The advantage of this system over the wires, this fellow thought, resided in the “fact” that radio waves take no time, unlike impulses in wires, to travel from one place to another. He was quickly disabused of this idea. No, the radio system still suffered from the time-gap obstacle.

But all this talk of impulse cartridges inspired Bert. “Look, we could feed each impulse cartridge with the same pattern of impulses it would have been receiving by radio but do so by such a method as to require no radio or wire transmission. All we need do is fix to each cartridge not a radio transmitter and receiver but an ‘impulse programmer,’ the sort of gadget that would play through whatever program of impulses you have previously given it. The great thing about this is that there is no longer any need for the impulse pattern going into one hemisphere to be actually caused, in part, by the pattern coming from the other. Therefore there need not be any wait for the transmission. The programmed cartridges can be so correlated with the rest of our stimulation of neural patterns that all of the timing can be just as it would have been if the hemispheres were together. And, yes, then it will be easy to fix each hemisphere in a separate bath—perhaps one in the laboratory here and one in the laboratory across town, so that we may employ the facilities of each laboratory in working with merely half a brain. This will make everything easier. And we can then bring in more people; there are many who’ve been bothering us to let them join our project.”

But now Cassander was even more worried. “We have already disregarded the condition of proximity. Now we are about to abandon yet another condition of usual experience—that of actual causal connection. Granted you can be clever enough to get around what is usually quite necessary to an experience coming about. So now, with your programming, it will no longer be necessary for impulses in one half of the brain actually to be a cause of the completion of the whole-brain pattern in the other hemisphere in order for the whole-brain pattern to come about. But is the result still the bare fact of the whole-brain experience or have you, in removing this condition, removed an absolute principle of, an essential condition for, a whole-brain experience really being had?”

The answers to this were much as they had been to the other. How did the neural activity know whether a radio-controlled or programmed impulse cartridge fed it? How could this fact, so totally external to them, register with the neural structures underlying thought, speech, and every other item of awareness? Certainly it could not register mechanically. Wasn’t the result then precisely the same with tape as with wire except that now the time-gap problem had been overcome? And wouldn’t a properly hooked-up mouth even report the experiences as nicely after the taped as after the wired assistance with crossing impulses?

The next innovation came soon enough—when the question was raised about whether it was at all important, since each hemisphere was now working separately, to synchronize the two causally unconnected playings of the impulse patterns of the hemispheres. Now that each hemisphere would in effect receive all the impulses that in a given experience it would have received from the other hemisphere—and receive them in such a way as would work perfectly with the timing of the rest of its impulses—and since this fine effect could be achieved in either hemisphere quite independent of its having yet been achieved in the other, there seemed no reason for retaining what Cassander sadly pointed to as the “condition of synchronization.” Men were heard to say, “How does either hemisphere know, how could it register when the other goes off, in the time of the external observer, anyway? For each hemisphere what more can we say than that it is just precisely as if the other had gone off with it the right way? What is there to worry about if at one lab they run through one half of a pattern one day and at the other lab they supply the other hemisphere with its half of the pattern another day? The pattern gets run through fine. The experience comes about. With the brain parts hooked up properly to a mouth, our friend could even report his experience.”

There was also some discussion about whether to maintain what Cassander called “topology”—that is, whether to keep the two hemispheres in the general spatial relation of facing each other. Here too Cassander’s warnings were ignored.

Ten-centuries later the famous project was still engrossing men. But men now filled the galaxy and their technology was tremendous. Among them were billions who wanted the thrill and responsibility of participating in the “Great Experience Feed.” Of course, behind this desire lay the continuing belief that what men were doing in programming impulses still amounted to making a man have all sorts of experiences.

But in order to accommodate all those who now wished to participate in the project, what Cassander had called the “conditions” of the experiencing had, to the superficial glance, changed enormously. (Actually, they were in a sense more conservative than they had been when we last saw them, because, as I shall explain later, something like “synchronization” had been restored.) Just as earlier each hemisphere of the brain had rested in its bath, now each individual neuron rested in one of its own. Since there were billions of neurons, each of the billions of men could involve himself with the proud task of manning a neuron bath.

To understand this situation properly, one must go back again ten centuries, to what had occurred as more and more men had expressed a desire for a part of the project. First it was agreed that if a whole-brain experience could come about with the brain split and yet the two halves programmed as I have described, the same experience could come about if each hemisphere too were carefully divided and each piece treated just as each of the two hemispheres had been. Thus each of four pieces of brain could now be given not only its own bath but a whole lab—allowing many more people to participate. There naturally seemed nothing to stop further and further divisions of the thing, until finally, ten centuries later, there was this situation—a man on each neuron, each man responsible for an impulse cartridge that was fixed to both ends of that neuron—transmitting and receiving an impulse whenever it was programmed to do so.

Meanwhile there had been other Cassanders. After a while none of these suggested keeping the condition of proximity, since this would have so infuriated all his fellows who desired to have a piece of the brain. But it was pointed out by such Cassanders that the original topology of the brain, that is, the relative position and directional attitude of each neuron, could be maintained even while the brain was spread apart; and also it was urged by them that the neurons continue to be programmed to fire with the same chronology—the same temporal pattern—that their firings would have displayed when together in the brain.

But the suggestion about topology always brought a derisive response. A sample: “How should each of the neurons know, how should it register on a single neuron, where it is in relation to the others? In the usual case of an experience it is indeed necessary for the neurons, in order at all to get firing in that pattern that is or causes the experience, to be next to each other, actually causing the firing of one another, in a certain spatial relation to one another—but the original necessity of all these conditions is overcome by our techniques. For example, they are not necessary to the bare fact of the coming about of the experience that we are now causing to be had by the ancient gentleman whose neuron this is before me. And if we should bring these neurons together into a hookup with a mouth, then he would tell you of the experience personally.”

Now as for the second part of the Cassanderish suggestion, the reader might suppose that after each successive partitioning of the brain, synchronization of the parts would have been consistently disregarded, so that eventually it would have been thought not to matter when each individual neuron was to be fired in relation to the firings of the other neurons just as earlier the condition had been disregarded when there were only two hemispheres to be fired. But somehow, perhaps because disregarding the timing and order of individual neuron firings would have reduced the art of programming to absurdity, the condition of order and timing had crept back, but without the Cassanderish reflectiveness. “Right” temporal order of firings is now merely assumed as somehow essential to bringing about a given experience by all those men standing before their baths and waiting for each properly programmed impulse to come to its neuron.

But now, ten centuries after the great project’s birth, the world of these smug billions was about to explode. Two thinkers were responsible.

One of these, named Spoilar, had noticed one day that the neuron in his charge was getting a bit the worse for wear. Like any other man with a neuron in that state, he merely obtained another fresh one just like it and so replaced the particular one that had gotten worn-tossing the old one away. Thus he, like all the others, had violated the Cassanderish condition of “neural identity”—a condition never taken very seriously even by Cassanders. It was realized that in the case of an ordinary brain the cellular metabolism was always replacing all the particular matter of any neuron with other particular matter, forming precisely the same kind of neuron. What this man had done was really no more than a speeding up of this process. Besides, what if, as some Cassanders had implausibly argued, replacing one neuron by another just like it somehow resulted, when it was eventually done to all the neurons, in a new identity for the experiencer? There still would be an experiencer having the same experience every time the same patterns of firings were realized (and what it would mean to say he was a different experiencer was not clear at all, even to the Cassanders). So any shift in neural identity did not seem destructive of the fact of an experience coming about.

This fellow Spoilar, after he had replaced the neuron, resumed his waiting to watch his own neuron fire as part of an experience scheduled several hours later. Suddenly he heard a great crash and a great curse. Some fool had fallen against another man’s bath, and it had broken totally on the floor when it fell. Well, this man whose bath had fallen would just have to miss out on any experiences his neuron was to have been part of until the bath and neuron could be replaced. And Spoilar knew that the poor man had had one coming up soon.

The fellow whose bath had just broken walked up to Spoilar. He said “Look, I’ve done favors for you. I’m going to have to miss the impulse coming up in five minutes—that experience will have to manage with one less neuron firing. But maybe you’d let me man yours coming up later. I just hate to miss all the thrills coming up today!”

Spoilar thought about the man’s plea. Suddenly, a strange thought hit him. “Wasn’t the neuron you manned the same sort as mine?”

“Yes.”

“Well, look. I’ve just replaced my neuron with another like it, as we all do occasionally. Why don’t we take my entire bath over to the old position of yours? Then won’t it still be the same experience brought about in five minutes that it would have been with the old neuron if we fire this then, since this one is just like the old one? Surely the bath’s identity means nothing. Anyway, then we can bring the bath back here and I can use the neuron for the experience it is scheduled to be used for later on. Wait a minute! We both believe the condition of topology is baloney. So why need we move the bath at all? Leave it here; fire it for yours; and then I’ll fire it for mine. Both experiences must still come about. Wait a minute again! Then all we need do is fire this one neuron here in place of all the firings of all neurons just like it! Then there need be only one neuron of each type firing again and again and again to bring about all these experiences! But how would the neurons know even that they were repeating an impulse when they fired again and again? How would they know the relative order of their firings? Then we could have one neuron of each sort firing once and that would provide the physical realization of all patterns of impulses (a conclusion that would have been arrived at merely by consistently disregarding the necessity of synchronization in the progress from parted hemispheres to parted neurons). And couldn’t these neurons simply be any of those naturally firing in any head? So what are we all doing here?”

Then an even more desperate thought hit him, which he expressed thus: “But if all possible neural experience will be brought about simply in the firing once of one of each type of neuron, how can any experiencer believe that he is connected to anything more than this bare minimum of physical reality through the fact of his having any of his experiences? And so all this talk of heads and neurons in them, which is supposedly based on the true discovery of physical realities, is undermined entirely. There may be a true system of physical reality, but if it involves all this physiology we have been hoodwinked into believing, it provides so cheaply for so much experience that we can never know what is an actual experience of it, the physical reality. And so belief in such a system undermines itself. That is, unless it’s tempered with Cassanderish principles.”

The other thinker, coincidentally also named Spoilar, came to the same conclusion somewhat differently. He enjoyed stringing neurons. Once he got his own neuron, the one he was responsible for, in the middle of a long chain of like neurons and then recalled he was supposed to have it hooked up to the cartridge for a firing. Not wanting to destroy the chain, he simply hooked the two end neurons of the chain to the two poles of the impulse cartridge and adjusted the timing of the cartridge so that the impulse, traveling now through this whole chain, would reach his neuron at just the right time. Then he noticed that here a neuron, unlike one in usual experience, was quite comfortably participating in two patterns of firings at once—the chain’s, which happened to have proximity and causal connection, and the programmed experience for which it had fired. After this Spoilar went about ridiculing “the condition of neural context.” He’d say, “Boy, I could hook my neuron up with all those in your head, and if I could get it to fire just at the right time, I could get it into one of these programmed experiences as fine as if it were in my bath, on my cartridge.”

Well, one day there was trouble. Some men who had not been allowed to join the project had come at night and so tampered with the baths that many of the neurons in Spoilar’s vicinity had simply died. Standing before his own dead neuron, staring at the vast misery around him, he thought about how the day’s first experience must turn out for the experiencer when so many neuron firings were to be missing from their physical realization. But as he looked about he suddenly took note of something else. Nearly everyone was stooping to inspect some damaged equipment just under his bath. Suddenly it seemed significant to Spoilar that next to every bath there was a head, each with its own billions of neurons of all sorts, with perhaps millions of each sort firing at any given moment. Proximity didn’t matter. But then at any given moment of a particular pattern’s being fired through the baths all the requisite activity was already going on anyway in the heads of the operators—in even one of those heads, where a loose sort of proximity condition was fulfilled too! Each head was bath and cartridge enough for any spread-brain’s realization: “But,” thought Spoilar, “the same kind of physical realization must exist for every experience of every brain—since all brains are spreadable. And that includes mine. But then all my beliefs are based on thoughts and experiences that might exist only as some such floating cloud. They are all suspect—including those that had convinced me of all this physiology in the first place. Unless Cassander is right, to some extent, then physiology reduces to absurdity. It undermines itself.”

Such thinking killed the great project and with it the spread-brain. Men turned to other weird activities and to new conclusions about the nature of experience. But what these were is another story.

Reflections

This weird tale seems at first to be a sly demolition of virtually all the ideas exploited in the rest of the book, a reductio ad absurdum of the assumptions about the relations between brain and experience that had seemed to be innocent and obvious. How might one resist the daffy slide to its conclusion? Some hints:

Suppose someone claimed to have a microscopically exact replica (in marble, even) of Michelangelo’s “David” in his home. When you go to see this marvel, you find a twenty-foot-tall roughly rectilinear hunk of pure white marble standing in his living room. “I haven’t gotten around to unpacking it yet,” he says, “but I know it’s in there.”

Consider how little Zuboff tells us of the wonderful “cartridges” and “impulse programmers” that get fastened to the various bits and pieces of brain. All they do, we learn, is provide their attached neuron, or group of neurons, with a lifetime supply of the right sort of impulses in the right order and timing. Mere beepers, we might be inclined to think. But reflect on what must actually be produced by these cartridges, by considering what would in fact be a vastly “easier” technological triumph. Crippling strikes close down all the television stations, so there is nothing to watch on TV; fortunately, IBM comes to the aid of all the people who are going insane without their daily dose of TV, by mailing them “impulse cartridges” to fasten to their TV sets; these cartridges are programmed to produce ten channels of news, weather, soap opera, sports, and so forth—all made up, of course (the news won’t be accurate news, but at least it will be realistic). After all, say the IBM people, we all know that television signals are just impulses transmitted from the stations; our cartridges simply take a shorter route to the receiver. What could be inside those wonderful cartridges, though? Videotapes of some sort? But how were they made? By videotaping real live actors, newscasters, and the like, or by animation? Animators will tell you that the task of composing, from scratch, all those frames without the benefit of filmed real action to draw upon is a gigantic task that grows exponentially as you try for greater realism. When you get right down to it, only the real world is rich enough in information to provide (and control) the signal trains needed to sustain channels of realistic TV. The task of making up a real world of perception (essentially the task Descartes assigned to an infinitely powerful deceiving demon in his Meditations) is perhaps possible in principle, but utterly impossible in fact. Descartes was right to make his evil demon infinitely powerful—no lesser deceiver could sustain the illusion without falling back on the real world after all and turning the illusion back into a vision of reality, however delayed or otherwise skewed.

These points strike glancing blows against Zubof’s implicit argument. Can they be put into fatal combinations? Perhaps we can convince ourselves that his conclusions are absurd by asking if a similar argument couldn’t be marshalled to prove that there is no need for books. Need we not simply print the whole alphabet just once and be done with all of book publishing? Who says we should print the whole alphabet? Will not just one letter, or one stroke do? One dot?

The logician Raymond Smullyan, whom we shall meet later in this book, suggests that the proper way to learn to play the piano is to become intimate with each note individually, one at a time. Thus, for instance, you might devote an entire month to practicing just middle C, perhaps only a few days each to the notes at the ends of the keyboard. But let’s not forget rests, for they are an equally essential part of music. You can spend a whole day on whole-note rests, two days on half-note rests, four days on quarter-note rests and so on. Once you’ve completed this arduous training, you’re ready to play anything! It sounds right, but, somehow, slightly wrong as well …

The physicist John Archibald Wheeler once speculated that perhaps the reason all electrons are alike is that there is really only one electron, careening back and forth from the ends of time, weaving the fabric of the physical universe by crossing its own path innumerable times. Perhaps Parmenides was right: there is only one thing! But this one thing, so imagined, has spatiotemporal parts that enter into astronomically many relations with its other spatiotemporal parts, and this relative organization, in time and in space, matters. But to whom? To the portions of the great tapestry that are perceivers. And how are they distinguished from the rest of the tapestry?

D.C.D.

D.R.H.