GODEL, ESCHER,
BACH:
an Eternal Golden Braid
By Douglas R. Hofstadter
--
đď¸
⢠⢠⢠Ant Fugue
đď¸
. . . then, one by one, the four voices of the fugue chime in.)
Achilles: I know the rest of you wonât 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"!
CCrab: I know the rest of you wonât 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 impvrtant one: "HOLISM"!
Achilles: Now hold on a minute. You must be seeing things. Itâs 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 the picture doesnât say what I said it says!
Anteater: I know the rest of you wonât 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. Itâs plain as day
that the message of this picture is "HOLISM", not "REDUCTION,SM"!
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 doesnât say what I said it says.
Achilles: Donât 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 com-
posed 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 donât know, but I
know what I see, and what I see is "HOLISM", plain as day. How you see
anything else is beyond me.
Antedter: 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 com-
posed 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 donât
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,
FIGURE 60. [Drawing by the authoT.]
there are indeed three "HOLISMâââS, but each one of them is composed
out of smaller copies of the word ¡âREDUCTIONISM". And in complemen-
tary fashion, in the right-hand piece, there is indeed one "REDUC-
TIONISM", 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 thes.e strange expressions, "HOLISM" and
"REDUCTIONISM"Â .
Crab: HOLISM is the most natural thing in the world to grasp. Itâs 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. Itâs
simply the belief that "a whole can be understood completely if you
understand its parts, and the nature of their 'sum"â. 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 con-
sciousness 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 inevi-
tably fall far short of explaining where the consciousness experienced
by an ant colony arises from.
Achilles: Oh, no! The last thing which 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 under-
stood 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 cowâs moo. Iâll have none of this
Zen wishy-washiness.
Crab: Ridiculous! Your "MU" is as silly as a kittenâs mew. Iâll have none of
this Zen washy-wishiness.
Achilles: Oh, dear! Weâre 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 wonât 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: HMU"!
aust 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 to resolve
this dilemma-but apparently, you have seen no further than I myself
saw. Oh, well, I guess I should feel pleased to have seen as 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 doesnât say what I said it 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 you
imagine, Achilles-an octave lower (figuratively speaking). But for
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 out 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 ant 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 have much to learn from 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 led 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 my
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 everyday situa-
tions. It can be quite tragic. I attempt to remedy the situation by,
uhh-removingâ-the defective part of the colony. These operations
are sometimes quite involved, and of course years of study are re-
quired before one can perform them.
Achilles: But-isnât it true that, before one can suffer from speech Im-
pairment, one must have the faculty of speech?
Anteater: Right.
Achilles: Since ant colonies donât have that faculty, I am a little confused.
Crab: Itâs too bad, Achilles, that you werenât 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, sheâs not really anybodyâs aunt.
Anteater: But the poor dear insists that everybody should call her that,
even strangers. Itâs just one of her many endearing quirks.
Crab: Yes, Aunt Hillary is quite eccentric, but such a merry old soul. Itâs a
shame I didnât have you over to meet her last week.
Anteater: Sheâs 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. Itâs 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, Iâm 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 Iâll 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. Thatâs 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! Thatâs not the way it happens. Ant colonies donât
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 theyâre saying just like a book.
Achilles: Remarkable. And can you communicate back to them?
Anteater: Without any trouble at all. Thatâs 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, Iâll say
that.
Anteater: I think you are still having some difficulty realizing the differ-
ence 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 couldnât
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 donât 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 conversa-
tion.
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 ahd then upon a
morsel of food ... They are free to do what they want to do, and with
that freedom, I donât see at all how their behavior, seen as a whole, can
amount to anything coherent---{~specially 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 donât 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, in-
volving 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 unpre-
dictable 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 com-
pletely 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. Isnât
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 gnatchungry swallow; every twist, every
turn foreordained by the neural structure in Achilles' brain, until
sensory input messages interfere.
Achilles: Normally, I think that IâM 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 donât
know who-or what-I am, if anything.
Tortoise: Youâll 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 arenât 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 lpng 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 thatâs a far cry from the ability to
understand the world, or to talk about it!
Anteater: That highlights a very interesting difference between the expla-
nation 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 struc-
ture than molecules, except the full gas itself. On the other hand, in an
ant colony, you canât 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",
arenât they?
Anteater: Thatâs correct. Aside from the queen, there are males, who do
practically nothing towards 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 Achil-
les is somewhat naIve. 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 wonât fight!
Anteater: Well, as I just said, they really arenât soldiers at all. Itâs the
workers who are soldiers; the soldiers are just lazy fatheads.
Achilles: Oh, how disgraceful! Why, if I were an ant, Iâd put some disci-
pline in their ranks! Iâd knock some sense into those fatheads!
Tortoise: If you were an ant? How could 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 propo-
sition 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 ac-
complished in a colony, and individual ants develop specializations.
Usually an antâs specialization changes as the ant ages. And of course it
is also dependent on the antâs caste. At anyone 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: Iâm 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 which allows the colony to have the complex-
ity which 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 diffe-
rently from the way they were before I arrived.
Achilles: But thatâs understandable, since youâre a dreaded enemy of the
colony.
Anteater: Oh, no. I must reiterate that, far from being an enemy of the
colony, I am Aunt Hillaryâs favorite companion. And Aunt Hillary is
my favorite aunt. I grant you, Iâm quite feared by all the individual
ants in the colony-but thatâs 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: Thatâs 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 thereâs a vital point. It requires some elaboration. You see,
what it comes down to is how you choose to describe the caste distribu-
tion. If you continue to think in terms of the lower levels-individual
ants-then you miss the forest for the trees. Thatâsjust too microscopic
a level, and when you think microscopically, youâre bound to miss some
large-scale features. Youâve 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 can 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. Letâs 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 a
while are the teams, and the reason they donât 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 youâre 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 an 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 of struc-
ture falling somewhere in between the single-ant level and the colony
level.
Anteater: Precisely. There exists a special kind of team, which I call a
"signal"-and all the higher levels of structure are based on signals. In
fact, all the higher entities are collections of signals acting in concert.
There are teams on higher levels whose members are not 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 transport
ants of various specializations to appropriate parts of the colony. So the
typical story of a signal is thus; it (omes 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 thatâs 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? Itâs 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 ex-
plaining 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 towards 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 donât
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. Letâs 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, Iâm beginning to see things from two differ-
ent vantage points. From an antâs-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
COLONYâS 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 donât suppose you
see "meaning" and "purpose" in the bubbles in boiling water-or do
you?
Crab: No, but-
Anteater: Now thatâs 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 distribu-
tion 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 mean-
ing, too.
Crab: Evolution certainly works some miracles. You never know the next
trick it will pull out of its sleeve. fâor instance, it wouldnât 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-thatâs 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.
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: Iâd like some, too, Mr. Crab-
Achilles: -in a musical fugue
Anteater: -if it isnât 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: Thatâs an interesting thought, Achilles. But itâs unlikely that
anyone could draw such a picture in a convincing way.
Achilles: Thatâs 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, s.ignals 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 distribu-
tion throughout the colony, and are doing so in response to the
internal needs of the colony-which in turn reflect the external situa-
tion which the colony is faced with. Therefore the caste distribution, as
you said, Dr. Anteater, gets continually updated in a way which ulti-
mately 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 under-
standing how it was possible to describe the caste distribution as encod-
ing 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, isnât it? I just had no idea that ant
colonies had such an abstract structure.
Anteater: Yes, itâs 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 under-
lying 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 couldnât set up the map
in its glorious detail. But-and correct me if Iâm wrong, Mr. Crab-I
would surmise that the brain counterpart to an ant colonyâs 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 donât 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 donât 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 couldnât 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: Iâll do so, but Iâm 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 per-
fectly 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 charac-
terized 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; letâs 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 loca-
tion 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 combi-
nations 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 de-
scription, since teams consist of clumps of ants. A team-by-team de-
scription 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
wouldnât 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: Iâm 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 Dick.ens 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 'tâ-concept, the 'h' -concept, and the
'e' -concept-and every time, those concepts are as they were the pre-
ceding 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! Iâd 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 couldnât 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 suc-
ceed 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 proba-
bly perceive nothing more than a rearrangement of ants.
Achilles: Iâm sure thatâs 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, hereâs that charming Dr.
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 itâs 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 manip-
ulating, if the symbols are themselves active? Who is the agent?
Anteater: This gets back to the question which you earlier raised about
purpose. Youâre 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 which remain over time. It is this partially constant,
partially varying system which 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: Thatâs quite a strange characterization of the notion of who I am.
Iâm 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: Thatâs 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 only learns 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 m
many respects.
Achilles: I have never seen nor read any brain either, however.
Anteater: What about your OWN brain? Arenât you aware of your own
thoughts? Isnât 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 only see the topmost level?
Anteater: Thatâs the way it is, with conscious systems. They perceive them-
selves 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 which are
constantly updating themselves so that they reRect the overall state of
the brain itself, always on the symbol level?
Anteater: Certainly. In any conscious system there are symbols which
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 only capable of register-
ing that activity in one way-on the symbol level; and I am completely
insensitive to the lower levels. It is like being able to read a Dickens
novel by direct visual perception, without ever having learned the
letters of the alphabet. I canât 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: Youâre right-I bypassed the lower levels, and saw only the top. I
wonder if Iâm missing all sorts of meaning on lower levels of my brain
as well, by reading only the symbol level. Itâs too bad that the top level
doesnât 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 naive to hope that the top level encodes anything from the
bottom level-it probably doesnât 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: Thatâs absolutely true. (Picks up the MU-picture, to inspect it more
closely.) Hmm ... Thereâs something strange about the smallest letters
in this picture; theyâre very wiggly ...
Anteater: Let me take a look. (Peers closely at the MU-picture.) I think thereâs
yet another level, which all of us missed!
Tortoise: Speak for yourself, Dr. Anteater.
Achilles: Oh, no-that canât be! Let me see. (Looks very carefully.) I know the
rest of you wonât believe this, but the message of this picture is 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 hadnât 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 donât see any way to do so, since we have no idea why that
particular picture is in the Crabâs 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, injust a moment, comes an organ point.
Achilles: Isnât 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, youâre 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, towards the end of this
fugue.
Achilles: Oh, good. Youâll point them out in advance, wonât 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 youâll 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. (Sheâs always been most gener-
ous 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 particu-
larly 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. Specifical-
ly, 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
didnât 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, III
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 Hillaryâs structure,
but for all I know, she may not even be aware of this internal com-
munism. 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.
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, thereâs 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! Itâs just a few bunches of letters. Letâs see-there are various
numbers of the letters ']â, 'Sâ, 'Bâ, 'mâ, 'aâ, and 'tâ. Itâs 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 'fâ, 'eâ, 'râ, 'Aâ, 'Câ, 'Hâ, 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 upper-case letters
which grow as you move to the right.
Tortoise: Do they spell anything?
Achilles: Ah ... "J. S. BACH". Oh! I understand now. Itâs Bachâs 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, youâve got Fermat on the brain, I do believe. You see Fer-
matâs 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? Iâm beginning to feel
stupid.
Tortoise: There, there, Achilles-donât feel bad. Iâm sure you wonât miss
Fugueâs 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 Hillaryâs prop-
erty?
Anteater: The former owner was an extraordinary individual, one of the
most creative ant colonies who ever lived. His name was Johant Sebas-
tiant Fermant, and he was a mathematiciant by vocation, but a
musiciant by avocation.
Achilles: How very versantile 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. SÂ .F. Since the storm came utterly without
warning, the ants got completely disoriented and confused. The intri-
cate organization which 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 obviously would
spell the end of poor J. S. F.?
Anteater: Actually, no. The ants managed to survive, every last one of
them, by crawling onto various sticks and logs which 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 distribu-
tion was utterly destroyed, and the ants themselves had no ability to
reconstruct what had once before been such a finely tuned organiza-
tion. They were as helpless as the pieces of Humpty Dumpty in putting
themselves back together again. I myself tried, like all the kingâs horses
and all the kingâs 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 which 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 as
Fermant was?
Anteater: Well, originally she was, yes. By now, some of the older ants have
died, and been replaced. But there are still many holdovers from the
J. S. F.-days.
Crab: And canât you recognize some of J. S. F.âs 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 several distinct
ways to rearrange a group of parts to form a "sum". And 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: Iâve 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 donât 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 rema! Kable contributions to number theory. Aunt
Hillary, on the other hand, is remarkably dull-witted in anything 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 Sebastiantâs contributions?
Anteater: Very well, then. (Pauses for a moment to sip his tea, then resumes.)
Have you heard of Fourmiâs infamous "Well-Tested Conjecture"?
Achilles: Iâm not sure ... It sounds strangely familiar, and yet I canât quite
place it.
Anteater: Itâs 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 contain-
ing the equation
He immediately realized that this equation has infinitely many solu-
tions a, b, c, and then wrote in the margin the following notorious
comment:
... Ant Fugue
The equation
Na+Nb=Nc
has solutions in positive integers a, b, c, and n only when n = 2 (and
then there are infinitely many triplets a, b, c which satisfy the equa-
tion); but there are no solutions for n > 2. I have discovered a truly
marvelous proof of this statement, which, unfortunately, is so small
that it would be well-nigh invisible if written in the margin.
Ever since that year, some three hundred days ago, mathematiciants
have been vainly trying to do one of two things: either to prove
Fourmiâs claim, and thereby vindicate Fourmiâs 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 ofn-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 Fourmiâs name.
It now goes under the name "Johant Sebastiantâs Well-Tested Conjec-
ture".
Achilles: Shouldnât it be called a "Theorem" rather than a "Conjecture", if
itâs finally been given a proper proof?
Anteater: Strictly speaking, youâre 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 pub-
lishing 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 Sebastiantâs description of it, which
he wrote in the margin of his copy of Buxtehudeâs Preludes and
Fugues for Organ. The last words which he wrote before his tragic
demise were:
I have composed a truly marvelous fugue. In it, I have added
together the power of 24 keys, and the power of 24 themes; I came
up with a fugue with the power of 24 voices. Unfortunately, this
margin is too narrow to contain it.
And the unrealized masterpiece simply goes by the name, "Fermantâs
Last Fugue".
Achilles: Oh, that is unbearably tragic.
Tortoise: Speaking of fugues, this fugue which we have been listening to is
nearly over. Towards 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: itâs "HOLISMIONISM", written in
large letters that first shrink and then grow back to their original size.
But that doesnât make any sens-e, because itâs not a word. Oh me, oh
myl (Passes it to the Anteater.)
Anteater: Well, what have we here? Oh, I see: itâs "REDUCTHOLISM", written
in small letters that first grow and then shrink back to their original
size. But that doesnât make any sense, because itâs not a word. Oh my,
oh mel (Passes it to Achilles.)
Achilles: I know the rest of you wonât 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.)
Tortoise: I know the rest of you wonât 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-l heard the new twist on the theme this timel 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.
GODEL,
ESCHER,
BACH:
an Eternal Golden Braid
Douglas R. Hofstadter
Ant Fugue page 311
đď¸