AFTERWORD
                      Marvin Minsky

   In real life, you often have to deal with things you
don't completely understand. You drive a car, not
knowing how its engine works. You ride as passenger
in someone else's car, not knowing how that driver
works. And strangest of all, you sometimes drive your-
self to work, not knowing how you work, yourself.
   To me, the import of True Names is that it is about
how we cope with things we don't understand. But,
how do we ever understand anything in the first
place? Almost always, I think, by using analogies in
one way or another--to pretend that each alien thing
we see resembles something we already know. When
an object's internal workings are too strange, comp-
licated, or unknown to deal with directly, we extract
whatever parts of its behavior we can comprehend
and represent them by familiar symbol--or the names
of familiar things which we think do similar things.
That way, we make each novelty at least appear to be
like something which we know from the worlds of
our own pasts. It is a great idea, that use of symbols;
it lets our minds transform the strange into the
commonplace. It is the same with names.
   Right from the start, True Names shows us many
forms of this idea, methods which use symbols, names,
and images to make a novel world resemble one
where we have been before. Remember the doors to
Vinge's castle? Imagine that some architect has in-
vented a new way to go from one place to another: a
scheme that serves in some respects the normal func-
tions of a door, but one whose form and mechanism
is so entirely outside our past experience that, to see
it, we'd never think of it as a door, nor guess what
purposes to use it for. No matter: just superimpose,
on its exterior, some decoration which reminds one of
a door. We could clothe it in rectangular shape, or
add to it a waist-high knob, or a push-plate with a
sign lettered "EXIT" in red and white, or do whatever
else may seem appropriate--and every visitor from
Earth will know, without a conscious thought, that
pseudo-portal's purpose, and how to make it do its
job.
   At first this may seem mere trickery; after all, this
new invention, which we decorate to look like a door,
is not really a door. It has none of what we normally
expect a door to be, to wit: hinged, swinging slab of
wood, cut into wall. The inner details are all wrong.
Names and symbols, like analogies, are only partial
truths; they work by taking many-levelled descrip-
tions of different things and chopping off all of what
seem, in the present context, to be their least essen-
tial details--that is, the ones which matter least to
our intended purposes. But, still, what matters--when
it comes to using such a thing--is that whatever
symbol or icon, token or sign we choose should re-
mind us of the use we seek which, for that not-
quite-door, should represent some way to go from one
place to another. Who cares how it works, so long as
it works! It does not even matter if that "door" leads
to anywhere: in True Names, nothing ever leads
anywhere; instead, the protagonists' bodies never move
at all, but remain plugged-in to the network while
programs change their representations of the simu-
lated realities!
   Ironically, in the world True Names describes, those
representations actually do move from place to place--
but only because the computer programs which do
the work may be sent anywhere within the world-
wide network of connections. Still, to the dwellers
inside that network, all of this is inessential and
imperceptible, since the physical locations of the com-
puters themselves are normally not represented any-
where at all inside the worlds they simulate. It is only
in the final acts of the novel, when those partially-
simulated beings finally have to protect themselves
against their entirely-simulated enemies, that the pro-
grams must keep track of where their mind-computers
are; then they resort to using ordinary means, like
military maps and geographic charts.
   And strangely, this is also the case inside the ordi-
nary brain: it, too, lacks any real sense of where it is.
To be sure, most modem, educated people know that
thoughts proceed inside the head--but that is some-
thing which no brain knows until it's told. In fact,
without the help of education, a human brain has no
idea that any such things as brains exist. Perhaps we
tend to place the seat of thought behind the face,
because that's where so many sense-organs are located.
And even that impression is somewhat wrong: for
example, the brain-centers for vision are far away
from the eyes, away in the very back of the head,
where no unaided brain would ever expect them to
be.
   In any case, the point is that the icons in True
Names are not designed to represent the truth--that
is, the truth of how the designated object, or program,
works; that just is not an icon's job. An icon's pur-
pose is, instead, to represent a way an object or a
program can be used. And, since the idea of a use is
in the user's mind--and not connected to the thing it
represents--the form and figure of the icon must be
suited to the symbols that the users have acquired in
their own development. That is, it has to be con-
nected to whatever mental processes are already one's
most fluent, expressive, tools for expressing intentions.
And that's why Roger represents his watcher the way
his mind has learned to represent a frog.
   This principle, of choosing symbols and icons which
express the functions of entities--or rather, their users'
intended attitudes toward them--was already second
nature to the designers of earliest fast-interaction com-
puter systems, namely, the early computer games
which were, as Vemor Vinge says, the ancestors of
the Other Plane in which the novel's main activities
are set. In the 1970's the meaningful-icon idea was
developed for personal computers by Alan Kay's re-
search group at Xerox, but it was only in the early
1980's, after further work by Steven Jobs' research
group at Apple Computer, that this concept entered
the mainstream of the computer revolution, in the
body of the Macintosh computer.
   Over the same period, there have also been less-
publicized attempts to develop iconic ways to represent,
not what the programs do, but how they work. This
would be of great value in the different enterprise of
making it easier for programmers to make new pro-
grams from old ones. Such attempts have been less
successful, on the whole, perhaps because one is
forced to delve too far inside the lower-level details of
how the programs work. But such difficulties are too
transient to interfere with Vinge's vision, for there is
evidence that he regards today's ways of programming--
which use stiff, formal, inexpressive languages--as
but an early stage of how great programs will be
made in the future.
   Surely the days of programming, as we know it, are
numbered. We will not much longer construct large
computer systems by using meticulous but conceptu-
ally impoverished procedural specifications. Instead,
we'll express our intentions about what should be
done, in terms, or gestures, or examples, at least as
resourceful as our ordinary, everyday methods for
expressing our wishes and convictions. Then these
expressions will be submitted to immense, intelligent,
intention-understanding programs which will them-
selves construct the actual, new programs. We shall
no longer be burdened with the need to understand
all the smaller details of how computer codes work.
All of that will be left to those great utility programs,
which will perform the arduous tasks of applying
what we have embodied in them, once and for all, of
what we know about the arts of lower-level pro-
gramming. Then, once we learn better ways to tell
computers what we want them to get done, we will
be able to return to the more familiar realm of ex-
pressing our own wants and needs. For, in the end,
no user really cares about how a program works, but
only about what it does--in the sense of the intelligi-
ble effects it has on other things with which the user
is concerned.
   In order for that to happen, though, we will have to
invent and learn to use new technologies for "express-
ing intentions". To do this, we will have to break
away from our old, though still evolving, program-
ming languages, which are useful only for describing
processes. And this may be much harder than it
sounds. For, it is easy enough to say that all we want
to do is but to specify what we want to happen, using
more familiar modes of expression. But this brings
with it some very serious risks.
   The first risk is that this exposes us to the conse-
quences of self-deception. It is always tempting to
say to oneself, when writing a program, or writing an
essay, or, for that matter, doing almost anything, that
"I know what I would want, but I can't quite express
it clearly enough". However, that concept itself re-
flects a too-simplistic self-image, which portrays one's
own self as existing, somewhere in the heart of one's
mind (so to speak), in the form of a pure, uncompli-
cated entity which has pure and unmixed wishes,
intentions, and goals. This pre-Freudian image serves
to excuse our frequent appearances of ambivalence;
we convince ourselves 'that clarifying our intentions
is a mere matter of straightening-out the input-output
channels between our inner and outer selves. The
trouble is, we simply aren't made that way, no matter
how we may wish we were.
   We incur another risk whenever we try to escape
the responsibility of understanding how our wishes
will be realized. It is always dangerous to leave much
choice of means to any servants we may choose--no
matter whether we program them or not. For, the
larger the range of choice of methods they may use,
to gain for us the ends we think we seek, the more
we expose ourselves to possible accidents. We may
not realize, perhaps until it is too late to turn back,
that our goals were misinterpreted, perhaps even
maliciously, as in such classic tales of fate as Faust,
the Sorcerer's Apprentice, or The Monkey's Paw (by
W.W. Jacobs).
   The ultimate risk, though, comes when we greedy,
lazy, master-minds are able at last to take that final
step: to design goal-achieving programs which are
programmed to make themselves grow increasingly
powerful, by using learning and self-evolution meth-
ods which augment and enhance their own capa-
bilities. It will be tempting to do this, not just for the
gain in power, but just to decrease our own human
effort in the consideration and formulation of our
own desires. If some genie offered you three wishes,
would not your first one be, "Tell me, please, what is
it that I want the most!" The problem is that, with
such powerful machines, it would require but the
slightest accident of careless design for them to place
their goals ahead of ours, perhaps the well-meaning
purpose of protecting us from ourselves, as in With
Folded Hands, by Jack Williamson),--or to protect us
from an unsuspected enemy, as in Colossus by D.H.
Jones, or because, like Arthur C. Clarke's HAL, the
machine we have built considers us inadequate to
the mission we ourselves have proposed, or, as in the
case of Vernor Vinge's own Mailman, who teletypes
its messages because it cannot spare the time to don
disguises of dissimulated flesh, simply because the
new machine has motives of its very own.
   Now, what about the last and finally dangerous
question which is asked toward True Names' end?
Are those final scenes really possible, in which a
human user starts to build itself a second, larger Self
inside the machine? Is anything like that conceivable?
And if it were, then would those simulated computer-
people be in any sense the same as their human
models before them; would they be genuine exten-
sions of those real people? Or would they merely be
new, artificial, person-things which resemble their
originals only through some sort of structural coinci-
dence? What if the aging Erythrina's simulation,
unthinkably enhanced, is permitted to live on inside
her new residence, more luxurious than Providence?
What if we also suppose that she, once there, will be
still inclined to share it with Roger--since no sequel
should be devoid of romance--and that those two
tremendous entities will love one another? Still, one
must inquire, what would those super-beings share
with those whom they were based upon? To answer
that, we have to think more carefully about what
those individuals were before. But, since these aren't
real characters, but only figments of an author's mind,
we'd better ask, instead, about the nature of our
selves.
   Now, once we start to ask about our selves, we'll
have to ask how these, too, work--and this is what I
see as the cream of the jest because, it seems to me,
that inside every normal person's mind is, indeed, a
certain portion, which we call the Self--but it, too,
uses symbols and representations very much like the
magic spells used by those players of the Inner World
to work their wishes from their terminals. To explain
this theory about the working of human consciousness,
I'll have to compress some of the arguments from
"The Society of Mind", my forthcoming book. In sev-
eral ways, my image of what happens in the human
mind resembles Vinge's image of how the players of
the Other Plane have linked themselves into their
networks of computing machines--by using superfi-
cial symbol-signs to control of host of systems which
we do not fully understand.
   Everybody knows that we humans understand far
less about the insides of our minds, than what we
know about the world outside. We know how ordi-
nary objects work, but nothing of the great comput-
ers in our brains. Isn't it amazing we can think, not
knowing what it means to think? Isn't it bizarre that
we can get ideas, yet not be able to explain what
ideas are. Isn't it strange how often we can better
understand our friends than ourselves?
   Consider again, how, when you drive, you guide
the immense momentum of a car, not knowing how
its engine works, or how its steering wheel directs
the vehicle toward left or right. Yet, when one comes
to think of it, don't we drive our bodies the same
way? You simply set yourself to go in a certain direc-
tion and, so far as conscious thought is concemed,
it's just like turning a mental steering wheel. All you
are aware of is some general intention--It's time to
go: where is the door?--and all the rest takes care of
itself. But did you ever consider the complicated pro-
cesses involved in such an ordinary act as, when you
walk, changing the direction you're going in? It is not
just a matter of, say, taking a larger or smaller step
on one side, the way one changes course when row-
ing a boat. If that were all you did, when walking,
you would tip over and fall toward the outside of the
turn.
   Try this experiment: watch yourself carefully while
turning--and you'll notice that, before you start the
turn, you tip yourself in advance; this makes you
start to fall toward the inside of the turn; then, when
you catch yourself on the next step, you end up
moving in a different direction. When we examine
that more closely, it all tums out to be dreadfully
complicated: hundreds of interconnected muscles,
bones, and joints are all controlled simultaneously, by
interacting programs which locomotion-scientists still
barely comprehend. Yet all your conscious mind need
do, or say, or think, is Go that way!--assuming that
it makes sense to speak of the conscious mind as
thinking anything at all. So far as one can see, we
guide the vast machines inside ourselves, not by us-
ing technical and insightful schemes based on know-
ing how the underlying mechanisms work, but by
tokens, signs, and symbols which are entirely as fan-
ciful as those of Vinge's sorcery. It even makes one
wonder if it's fair for us to gain our ends by casting
spells upon our helpless hordes of mental under-thralls.
   Now, if we take this only one more step, we see
that, just as we walk without thinking, we also think
without thinking! That is, we just as casually exploit
the agencies which carry out our mental work. Sup-
pose you have a hard problem. You think about it for
a while; then after a time you find a solution. Perhaps
the answer comes to you suddenly; you get an idea
and say, "Aha, I've got it. I'll do such and such." But
then, were someone to ask how you did it, how you
found the solution, you simply would not know how
to reply. People usually are able to say only things
like this:

"I suddenly realized..."
"I just got this idea..."
"It occurred to me that..."

   If we really knew how our minds work, we wouldn't
so often act on motives which we don't suspect, nor
would we have such varied theories in psychology.
Why, when we're asked how people come upon their
good ideas, are we reduced to superficial reproductive
metaphors, to talk about "conceiving" or "gestating",
or even "giving birth" to thoughts? We even speak of
"ruminating" or "digesting" as though the mind were
anywhere but in the head. If we could see inside our
minds we'd surely say more useful things than "Wait.
I'm thinking."
   People frequently tell me that they're absolutely
certain that no computer could ever be sentient,
conscious, self-willed, or in any other way "aware" of
itself. They're often shocked when I ask what makes
them sure that they, themselves, possess these admi-
rable qualities. The reply is that, if they're sure of
anything at all, it is that "I'm aware hence I'm aware."
   Yet, what do such convictions really mean? Since
"Self-awareness" ought to be an awareness of what's
going on within one's mind, no realist could maintain
for long that people really have much insight, in the
literal sense of seeing in.
   Isn't it remarkable how certainly we feel that we're
self-aware---that we have such broad abilities to know
what's happening inside ourselves? The evidence for
that is weak, indeed. It is true that some people
seem to have special excellences, which we some-
times call "insights", for assessing the attitudes and
motivations for other people. And certain individuals
even sometimes make good evaluations of themselves.
But that doesn't justify our using names like insight
or self-awareness for such abilities. Why not simply
call them "person-sights" or "person-awareness?" Is
there really reason to suppose that skills like these
are very different from the ways we learn the other
kinds of things we learn? Instead of seeing them as
"seeing in," we could regard them as quite the
opposite: just one more way of "figuring out." Per-
haps we learn about ourselves the same ways that we
learn about un-self-ish things.
   The fact is, the parts of ourselves which we call
"self aware" are only a small fraction of the entire
mind. They work by building simulated worlds of
their own--worlds which are greatly simplified, in
comparison with either the real world outside, or with
the immense computer systems inside the brain: sys-
tems which no one can pretend, today, to understand.
And our worlds of simulated awareness are worlds of
simple magic, wherein each and every imagined ob-
ject is invested with meanings and purposes. Con-
sider how one can but scarcely see a hammer except
as something to hammer with, or see a ball except as
something to throw and catch. Why are we so con-
strained to perceive things, not as they are, but as
they can be used? Because the highest levels of our
minds are goal-directed problem-solvers. That is to
say that all the machines inside our heads evolved,
originally, to meet various built-in or acquired needs,
for comfort and nutrition, for defense and for repro-
duction. Later, over the past few million years, we
evolved even more powerful sub-machines which, in
ways we don't yet understand, seem to correlate and
analyze to discover which kinds of actions cause which
sorts of effects; in a word, to discover what we call
knowledge. And though we often like to think that
knowledge is abstract, and that our search for it is
pure and good in itself--still, we ultimately use it for
its ability to tell us what to do to gain whichever
ends we seek (even when we conclude that in order
to do that, we may first need to gain yet more and
more knowledge). Thus, because, as we say, "know-
ledge is power", our knowledge itself is enmeshed in
those webs of ways we reach our goals. And that's
the key: it isn't any use for us to know, unless our
knowledge tells us what to do. This is so wrought
into the conscious mind's machinery that it seems
too obvious to state: no knowledge is of any use
unless we have a use for it.
   Now we come to see the point of consciousness: it
is the part of the mind most specialized for knowing
how to use the other systems which lie hidden in the
mind. But it is not a specialist in knowing how those
systems actually work, inside themselves. Thus, as
we said, one walks without much sense of how it's
done. It's only when those systems start to fail to
work well that consciousness becomes engaged with
small details. That way, a person who has sustained
an injured leg may start, for the first time, con-
sciously to make theories about how walking works:
To turn to the left, I'll have to push myself that
way--and then one has to figure out, with what? It is
often only when we're forced to face an unusually
hard problem that we become more reflective, and try
to understand more about how the rest of the mind
ordinarily solves problems; at such times one finds
oneself saying such things as, "Now I must get
organized. Why can't I concentrate on the important
questions and not get distracted by those other ines-
sential details?"
   It is mainly at such moments--the times when we
get into trouble--that we come closer than usual to
comprehending how our minds work, by engaging
the little knowledge we have about those mechanisms,
in order to alter or repair them. It is paradoxical that
these are just the times when we say we are "con-
fused", because it is very intelligent to know so much
about oneself that one can say that--in contrast merely
to being confused and not even knowing it. Still, we
disparage and dislike awareness of confusion, not real-
izing what a high degree of self-representation it
must involve. Perhaps that only means that conscious-
ness is getting out of its depth, and isn't really suited
to knowing that much about how things work. In any
case, even our most "conscious" attempts at self-
inspection still remain confined mainly to the prag-
matic, magic world of symbol-signs, for no human
being seems ever to have succeeded in using self-
analysis to find out very much about the programs
working underneath.


   So this is the irony of True Names. Though Vinge
tells the tale as though it were a science-fiction
fantasy--it is in fact a realistic portrait of our own,
real-life predicament! I say again that we work our
minds in the same unknowing ways we drive our
cars and our bodies, as the players of those futuris-
tic games control and guide what happens in their
great machines: by using symbols, spells and images--
as well as secret, private names. The parts of us
which we call "consciousness" sit, as it were, in front
of cognitive computer-terminals, trying to steer and
guide the great unknown engines of the mind, not by
understanding how those mechanisms work, but sim-
ply by selecting names from menu-lists of symbols
which appear, from time to time, upon our mental
screen-displays.
   But really, when one thinks of it, it scarcely could
be otherwise! Consider what would happen if our
minds indeed could really see inside themselves. What
could possibly be worse than to be presented with a
clear view of the trillion-wire networks of our nerve-
cell connections? Our scientists have peered at frag-
ments of those structures for years with powerful
microscopes, yet failed to come up with comprehen-
sive theories of what those networks do and how.
How much more devastating it would be to have to
see it all at once!
   What about the claims of mystical thinkers that
there are other, better ways to see the mind. One
recommended way is learning how to train the con-
scious mind to stop its usual sorts of thoughts and
then attempt (by holding very still) to see and hear
the fine details of mental life. Would that be any
different, or better, than seeing them through instru-
ments? Perhaps--except that it doesn't face the fun-
damental problem of how to understand a complicated
thing! For, if we suspend our usual ways of thinking,
we'll be bereft of all the parts of mind already trained
to interpret complicated phenomena. Anyway, even if
one could observe and detect the signals which emerge
from other, normally inaccessible portions of the mind,
these probably would make no sense to the systems
involved with consciousness, because they represent
unusually low level details. To see why this is so, let's
return once more to understanding such simple things
as how we walk.
   Suppose that, when you walk about, you were in-
deed able to see and hear the signals in your spinal
cord and lower brain. Would you be able to make any
sense of them? Perhaps, but not easily. Indeed, it is
easy to do such experiments, using simple bio-feedback
devices to make those signals audible and visible; the
result is that one may indeed more quickly learn to
perform a new skill, such as better using an injured
limb. However, just as before, this does not appear to
work through gaining a conscious understanding of
how those circuits work; instead the experience is
very much like business as usual; we gain control by
acquiring just one more form of semi-conscious
symbol-magic. Presumably, what happens is that a
new control system is assembled somewhere in the
nervous system, and interfaced with superficial sig-
nals we can know about. However, bio-feedback does
not appear to provide any different insights into how
learning works than do our ordinary, built-in senses.
In any case, our locomotion-scientists have been
tapping such signals for decades, using electronic
instruments. Using those data, they have been able
to develop various partial theories about the kinds of
interactions and regulation-systems which are involved.
However, these theories have not emerged from re-
laxed meditation about, or passive observation of those
complicated biological signals; what little we have
learned has come from deliberate and intense exploi-
tation of the accumulated discoveries of three centu-
ries of our scientists' and mathematicians' study of
analytical mechanics and a century of newer theories
about servo-control engineering. It is generally true
in science that just observing things carefully rarely
leads to new "insights" and understandings. One must
first have at least the glimmerings of the form of a
new theory, or of a novel way to describe: one needs
a "new idea". For the "causes" and the "purposes" of
what we observe are not themselves things that can
be observed; to represent them, we need some other
mental source to invent new magic tokens.
   But where do we get the new ideas we need? For
any single individual, of course, most concepts come
from the societies and cultures that one grows up in.
As for the rest of our ideas, the ones we "get" all by
ourselves, these, too, come from societies--but, now,
the ones inside our individual minds. For, a human
mind is not in any real sense a single entity, nor does
a brain have a single, central way to work. Brains do
not secrete thought the way livers secrete bile; a
brain consists of a huge assembly of sub-machines
which each do different kinds of jobs--each useful to
some other parts. For example, we use distinct sec-
tions of the brain for hearing the sounds of words, as
opposed to recognizing other kinds of natural sounds
or musical pitches. There is even solid evidence that
there is a special part of the brain which is special-
ized for seeing and recognizing faces, as opposed to
visual perception of other, ordinary things. I suspect
that there are, inside the cranium, perhaps as many
as a hundred kinds of computers, each with its own
somewhat different architecture; these have been ac-
cumulating over the past four hundred million years
of our evolution. They are wired together into a great
multi-resource network of specialists, which each
knows how to call on certain other specialists to get
things done which serve its purposes. And each of
these sub-brains uses its own styles of programming
and its own forms of representations; there is no
standard, universal language-code.
   Accordingly, if one part of that Society of Mind
were to inquire about another part, this probably would
not work because they have such different languages
and architectures. How could they understand one
another, with so little in common? Communication is
difficult enough between two different human tongues.
But the signals used by the different portions of the
human mind are even less likely to be even remotely
as similar as two human dialects with sometimes-
corresponding roots. More likely, they are simply too
different to communicate at all--except through sym-
bols which initiate their use.
   Now, one might ask, "Then, how do people doing
different jobs communicate, when they have different
backgrounds, thoughts, and purposes?" The answer
is that this problem is easier, because a person knows
so much more than do the smaller fragments of that
person's mind. And, besides, we all are raised in
similar ways, and this provides a solid base of com-
mon knowledge. Even so, we overestimate how well
we actually communicate. The many jobs that people
do may seem different on the surface, but they are all
very much the same, to the extent that they all have
a common base in what we like to call "common
sense"--that is, the knowledge shared by all of us.
This means that we do not really need to tell each
other as much as we suppose. Often, when we
"explain" something, we scarcely explain anything
new at all; instead, we merely show some examples
of what we mean, and some non-examples; these
indicate to the listener how to link up various struc-
tures already known. In short, we often just tell
"which" instead of "how".
   Consider how hard we find it to explain so many
seemingly simple things. We can't say how to bal-
ance on a bicycle, or distinguish a picture from a real
thing, or, even how to fetch a fact from memory.
Again, one might complain, It isn't fair to expect us
to be able to put in words such things as seeing or
balancing or remembering. Those are things we learned
before we even learned to speak! But, though that
criticism is fair in some respects, it also illustrates
how hard communication must be for all the sub-
parts of the mind which never learned to talk at
all--and these are most of what we are. The idea of
"meaning" itself is really a matter of size and scale: it
only makes sense to ask what something means in a
system which is large enough to have many meanings.
In very small systems, the idea of something having a
meaning becomes as vacuous as saying that a brick
is a very small house.
   Now it is easy enough to say that the mind is a
society, but that idea by itself is useless unless we
can say more about how it is organized. If all those
specialized parts were equally competitive, there would
be only anarchy, and the more we learned, the less
we'd be able to do. So there must be some kind of
administration, perhaps organized roughly in hier-
archies, like the divisions and subdivisions of an in-
dustry or of a human political society. What would
those levels do? In all the large societies we know
which work efficiently, the lower levels exercise the
more specialized working skills, while the higher lev-
els are concerned with longer-range plans and goals.
And this is another fundamental reason why it is so
hard to translate between our conscious and uncon-
scious thoughts! The kinds of terms and symbols we
use on the conscious level are primarily for express-
ing our goals and plans for using what we believe we
can do--while the workings of those lower level re-
sources are represented in unknown languages of
process and mechanism. So when our conscious probes
try to descend into the myriads of smaller and smaller
sub-machines which make the mind, they encounter
alien representations, used for increasingly special-
ized purposes.
   The trouble is, these tiny inner "languages" soon
become incomprehensible, for a reason which is sun-
pie and inescapable. This .is not the same as the
familiar difficulty of translating between two different
human languages; we understand the nature of that
problem: it is that human languages are so huge and
rich that it is hard to narrow meanings down: we call
that "ambiguity". But, when we try to understand the
tiny languages at the lowest levels of the mind, we
have the opposite problem--because the smaller be
two languages, the harder it will be to translate
between them, not because there are too many mean-
ings but too few. The fewer things two systems do,
the less likely that something one of them can do will
correspond to anything at all the other one can do.
And then, no translation is possible. Why is this worse
than when there is much ambiguity? Because, al-
though that problem seems very hard, still, even when
a problem seems hopelessly complicated, there al-
ways can be hope. But, when a problem is hopelessly
simple, there can't be any hope at all!
   Now, finally, let's return to the question of how
much a simulated life inside a world inside a ma-
chine could be like our ordinary, real life, "out here"?
My answer, as you know by now, is that it could be
very much the same--since we, ourselves, as we've
seen, already exist as processes imprisoned in ma-
chines inside machines. Our mental worlds are al-
ready filled with wondrous, magical, symbol-signs,
which add to everything we "see" a meaning and
significance.
   All educated people already know how different is
our mental world from the "real world" our scientists
know. For, consider the table in your dining room;
your conscious mind sees it as having a familiar
function, form, and purpose: a table is "a thing to put
things on". However, our science tells us that this is
only in the mind; all that's "really there" is a society
of countless molecules; the table seems to hold its
shape, only because some of those molecules are
constrained to vibrate near one another, because of
certain properties of the force-fields which keep them
from pursuing independent paths. Similarly, when
you hear a spoken word, your mind attributes sense
and meaning to that sound whereas, in physics, the
word is merely a fluctuating pressure on your ear,
caused by the collisions of myriads of molecules of
air--that is, of particles whose distances, this time
are less constrained.
   And so--let's face it now, once and for all: each
one of us already has experienced what it is like to be
simulated by a computer!
   "Ridiculous," most people say, at first: "I certainly
don't feel like a machine!"
   But what makes us so sure of that? How could one
claim to know how something feels, until one has
experienced it? Consider that either you are a ma-
chine or you're not. Then, if, as you say, you aren't a
machine, you are scarcely in any position of authority
to say how it feels to be a machine.
   "Very well, but, surely then, if I were a machine,
then at least I would be in a position to know that!"
   No. That is only an innocently grandiose presump-
tion, which amounts to claiming that, "I think, there-
fore I know how thinking works." But as we've seen,
there are so many levels of machinery between our
conscious thoughts and how they're made that saying
such a thing is as absurd as to say, "I drive, therefore
I know how engines work!"
   "Still, even if the brain is a kind of computer, you
must admit that its scale is unimaginably large. A
human brain contains many billions of brain cells--
and, probably, each cell is extremely complicated by
itself. Then, each cell is interlinked in complicated
ways to thousands or millions of other cells. You can
use the word "machine" for that but, surely, no one
could ever build anything of that magnitude!"
   I am entirely sympathetic with the spirit of this
objection. When one is compared to a machine, one
feels belittled, as though one is being regarded as
trivial. And, indeed, such a comparison in truly
insulting--so long as the name "machine" still car-
ries the same meaning it had in times gone by. For
thousands of years, we have used such words to
arouse images of pulleys, levers, locomotives, type-
writers, and other simple sorts of things; similarly, in
modern times, the word "computer" has evoked
thoughts about adding and subtracting digits, and
storing them unchanged in tiny so-called "memories".
However those words no longer serve our new pur-
poses, to describe machines that think like us; for
such uses, those old terms have become false names
for what we want to say. Just as "house" may stand
for either more, or nothing more, than wood and
stone, our minds may be described as nothing more,
and, yet far more, then just machines.
   As to the question of scale itself, those objections
are almost wholly out-of-date. They made sense in
1950, before any computer could store even a mere
million bits. They still made sense in 1960, when a
million bits costs a million dollars. But, today, that
same amount of money costs but a hundred dollars
(and our governments have even made the dollars
smaller, too)--and there already exist computers with
billions of bits.
   The only thing missing is most of the knowledge
we'll need to make such machines intelligent. Indeed,
as you might guess from all this, the focus of re-
search in Artificial Intelligence should be to find good
ways, as Vinge's fantasy suggests, to connect struc-
tures with functions through the use of symbols.
When, if ever, will that get done? Never say "Never".



           VERNOR VINGE

   A Hugo and Nebula Award finalist for True Names,
he is also the author of The Peace War, Grimm's
World, and a number of short stories. A mathemati-
cian and computer scientist, he has published arti-
cles in magazines such as Omni. He teaches at San
Diego State University.

           BOB WALTERS

   His illustrations have graced the pages of SF maga-
zines such as Analog and Isaac Asimov's SF Magazine.
He has also done a great deal of scientific illustration
for college texts, as well as general advertising
illustration. He lives in Philadelphia, Pennsylvania.

          MARVIN MINSKY

   Considered by many to be the father of Artificial
Intelligence, he has written especially for this book
an essay on the nature of intelligence, natural and
artificial. He is the director of the Artificial Intelli-
gence laboratory at the Massachusetts Institute of
Technology.