Consciousness The Last Great Frontier

If you are interested in the present, and want to know what is shaping the future, you must be interested in the research about CONSCIOUSNESS.
This incredible piece is by R. J. AUMANN a Nobel Price Winner of Economics.

Discussion Paper # 391 May 2005
תוילנויצרה רקחל זכרמ
CENTER FOR THE STUDY OF RATIONALITY
THE HEBREW UNIVERSITY OF JERUSALEM
URL: http://www.ratio.huji.ac.il/
Abstract

(Note: due to software translation of symbols you might find some duddles in the text. I will correct those as I work with the original text.)

Consciousness is the last great frontier of science. Here we discuss what
it is, how it difers fundamentally from other scientific phenomena, what
adaptive function it serves, and the difculties in trying to explain how it
works. The emphasis is on the adaptive function.
1. Introduction
Consciousness is the last great frontier of science. Sixty years ago, life was not
understood; it was a mystery. With the discovery of DNA, that mystery was
solved; today, we more or less understand, at least in principle, how life works.
But we do not at all understand how consciousness works.
We start by deÞning our terms; already there, there are dificulties. By con-
sciousness, we mean, in the Þrst instance, the ability to experience. To see, hear,
smell, feel, taste, desire, enjoy, sufer, like, dislike, love, hate, fear, become excited by an idea, be saddened by a loss. We do not mean to sense. A machine can
"sensor" also senses. Machines read; record sounds; detect odors, touches, and
favors; win at chess. They can even be programmed to exhibit a frownie, or
emit downbeat sounds when something isn't right. But presumably they do
not experience.
What, exactly, does "experience" mean? Ah, that is where the dificulty lies.
The word cannot be deÞned in technical terms that do not refer to the concept
itself. Experience cannot be defined in terms that a machine can understand.
If you yourself are not conscious have never experienced something then you
will not understand what the term means; just as little as congenitally deaf people
∗Center for the Study of Rationality, and Departments of Mathematics and Economics, The
Hebrew University of Jerusalem, 91904 Jerusalem, Israel
understand what music means. To be sure, they can understand about the vibra-
tions of taut strings, about air waves, about the workings of musical instruments,
and even about musical notation and rhythm; but they can never understand what
music is. For that, one must hear it. Similarly, someone who is not conscious
cannot understand experience.
Ernst Mayr, in The Growth of Biological Thought,1 distinguishes between two
fundamental questions in biology: “how” and “why”. “How” refers to mechanism,
“why” to function. The question “how do we digest food?” is answered by
describing the process, involving saliva, chewing, swallowing, processing in the
stomach and intestines, absorption into the bloodstream, and so on; and, disposing
of wastes. The question “why do we digest food?” is answered by saying that
food must be digested in order to provide vital ingredients for the functioning of
the body, particularly energy.
To these questions, we add a third, which logically comes before the other
two: “what”. This refers to the descriptive aspect of biology, and of science
in general. The answer to the question “what is digestion?” is that it is the
process whereby food is transformed to a state that the body can use. “What”
questions also include observational, descriptive, and classifying matters, and also
methodological or conceptual matters, like “what is a species?”
The remainder of this essay is divided into three sections: “What”, “Why”,
and “How”. In the Þrst, we discuss what consciousness is, and how it differs
radically from other scientiÞc phenomena. In the second, we discuss a possible
function of consciousness, from the evolutionary viewpoint; and the third discusses
the mechanism. Unfortunately, the “How” section is particularly short: We really
have nothing to say about this, other than to describe the difficulties.
2. What
We have deÞned consciousness as the ability to experience. This puts the phe-
nomenon into a completely different category from other scientiÞc phenomena, in
several ways.
(i) Unlike almost every–indeed every–other scientiÞc phenomenon, conscious-
ness is completely subjective. No veriÞable outside characteristics of consciousness
are known. No matter how complex an organism’s behavior is, a computer could
conceivably be programmed to mimic that behavior. An individual can observe
1Cambridge, Massachusetts: Belknap Press, 1982.
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consciousness only in himself.
SpeciÞcally, I can observe consciousness in myself only; I cannot be certain
that anybody else really is conscious. To be sure, since other people appear
roughly similar to me, and act similarly, I may surmise that they, too, are con-
scious; but I’m not certain. Each individual can be certain of consciousness only
in himself, where he directly observes it.
(ii) Whereas the phenomenon of consciousness is highly subjective, it is, para-
doxically, the only phenomenon of which the observer is absolutely certain. All
other phenomena and observations could conceivably be attributed to hallucina-
tions, dreams, and/or mental illness. But also hallucinations, dreams, and the
ravings of a madman are experiences; in each case, the observer is sure that he
is experiencing–is “conscious”–and he is right (we include dreams under the
heading of consciousness).
(iii) Sometimes, people express perplexity as to the nature of the problem.
They do not see anything mysterious about consciousness, and do not understand
in what way it is different from other neurological functions like, say, the regulation
of breathing. Asked whether a computer could in principle be conscious, they
answer, “why not?”
We are dumbfounded by this reaction, and can only conjecture that these
people are themselves not conscious. To me, it is evident that no combination
of silicon chips and wires could conceivably “experience” in the sense that I do.
Consciousness involves something beyond the merely physical and mechanical.
(iv) It seems only slightly less evident that no combination of off-the-shelf
chemicals could experience in the sense that I do. But here, we are entering a
gray area. By all indications, the day is not far off when it will be possible to
synthesize a human being.2 Will such a golem be conscious?
Each of the possible answers–“yes” and “no”–is problematic. “Yes” is prob-
lematic because a combination of chemicals is in principle no different from a
combination of silicon chips and wires, which we intuitively feel cannot experi-
ence. But “no” is also problematic, because there is no reason to believe that a
golem that is identical, molecule for molecule, with a live human being would not
in all respects–including consciousness–be like that human being.
2In an email message dated March 22, 2005, the U.S. National Academy of Sciences an-
nounced that “The U.S. National Academy of Sciences and other members of the InterAcademy
Panel, a worldwide organization of science academies, have stated that a worldwide ban on hu-
man reproductive cloning–a technique that attempts to produce a child–is justiÞed.” If it is
being banned, it is presumably within reach; and then, no bans can prevent it from happening.
3
(v) Are animals conscious? On the face of it, there is no reason to suppose
that they cannot be. But as stated above (in (i)), it is not even clear that all
humans–other than me–are conscious. By analogy with me, I can surmise that
other human beings are conscious; but the analogy is less compelling in the case
of animals. The further one gets from human beings on the evolutionary scale, the
less compelling the analogy. So the short answer is, “possibly; we don’t know.”
(vi) Consciousness may have levels. For example, dreaming is certainly an
expression of consciousness, but perhaps at a lower level than waking conscious-
ness. Newborn children, and the mentally impaired, may be conscious at a lower
level. In the opposite direction, people taking certain drugs sometimes report a
“heightened state of consciousness.”
Here again, we are at a loss, because we cannot really imagine what it is like to
be, say, a newborn child. We personally have never taken drugs, so cannot make
a judgment in the opposite direction either. We are stuck in our own conceptual
prison: Consciousness is about subjective experience, so it is difficult to imagine
levels of consciousness other than our own.
Though it may have various levels, its existence at any level already poses the
conceptual problems discussed here.
(vii) Conscious experience appears to be associated with certain physiological-
neurological processes in the brain, like the simultaneous Þring of many neurons
in a well-deÞned group of neurons.3 This, however, does not explain how con-
sciousness works–just as little as noticing that human reproduction is associated
with sexual intercourse explains how reproduction works.
(viii) Up to now we have discussed only the “input” component of conscious-
ness: experience. There are also two other vital components. One is the “process-
ing” component: thought, including intention. The other is the “output” compo-
nent: volition–consciously choosing to do something, and doing it. True, a person
could be conscious, but have no power to take any action–as when asleep, or as
a result of a totally debilitating stroke. But under most normal circumstances,
thought and volition are intimately associated with consciousness. Indeed, as
we shall presently see, it is the combination of all three elements–experience,
thought, and volition–that enables consciousness to perform its function.
3Communicated by Prof. Rafael Malach of the Weizmann Institute of Science, Rehovot.
Based on this observation, Professor Malach makes the fascinating suggestion that a group of
individuals acting in concert may also be conscious.
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3. Why
We next address the issue of “why”: What is the function of consciousness, from,
say, the evolutionary viewpoint?
The answer we propose is based on the two related notions of decentralizing
and decoupling–roughly speaking, splitting a difficult or complex task into several
easier or less complex tasks, often with the aid of an auxiliary “driving force.”
Here are some examples:
(i) Tearing a Manhattan telephone book in two–perhaps the grand-
daddy of all decoupling processes. Taken as is, it is very difficult. But if one Þrst
separates the book into a number of thinner parts, then one can easily tear each of
these parts in two, thus accomplishing the task. Here the difficult task is tearing
the whole book; the easier tasks are tearing each of the thinner parts; and the
decoupler is separating the entire book into the thinner parts.
(ii) Operating an economy. An economy can be centrally planned, as in a
Kibbutz (Israel cooperative village). A central planner decides how much of each
good will be allocated to each individual, how much–and where–each individual
will work, and so on. In theory, the entire economy of a whole country could be
planned in this way. That is the conception behind socialist economies, like that
of the former Soviet Union.
Centrally planning an entire economy is enormously complex and difficult. To
start with, the informational requirements–Þnding out what each person wants
to consume and what he is capable of producing–seem utterly beyond reach.
But even if that could somehow be achieved, the problemof getting the people to
do what you want them to do, and the sheer complexity of the task, makes the
efficient central planning of an entire economy practically unachievable. Indeed,
socialist economies like that of the Soviet Union achieve levels of efficiency that
are far below those of advanced “free” economies.
What enables free economies to work more efficiently is that they are, by and
large, decentralized. Within limits, each person seeks to acquire the goods and
services that he wants, and to work at the tasks that he wants and that he is
able to perform. There is no problem in getting the people to do what you want
them to do, as each individual makes his own choices. And, the complexity of the
task is greatly reduced, as the task of operating the economy is transferred from
a central planner to individuals, each planning only the segment of the economy
that interests him–usually, his own consumption and production. Instead of one
planner (or planning agencies) planning many billions of transactions, we have
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several million planners planning thousands of transactions each. The total size
of the task is perhaps roughly the same, but the task is decoupled into millions of
individual tasks–and so is much more easily accomplished.
The driving force that makes the whole process work is individual motivation.
Each individual is motivated to seek for himself the best “deal” that he can get–
the goods and the work that he likes most–and it is this that operates the entire
economy. That is Adam Smith’s “invisible hand.”
(iii) Money and prices. Primitive decentralized markets work by barter:
Two or more people get together and exchange goods or services, to the mutual
beneÞt of all parties to the transaction; the process may be repeated as often
as desired. One may hope that the Þnal outcome is optimal, in the sense that
no traders could have done better by trading with each other.4 In practice, in
reasonably large markets–or even in fairly small ones–identifying the bartering
groups, and deciding on the barters to be implemented, is so complex, involved,
and fraught with uncertainty that barter is unlikely to achieve an outcome that
is anywhere close to optimal.
Enter the institutions of money and prices. Rather than bartering, each trader
sells his goods at market prices; with the proceeds he buys the goods he desires,
again at market prices. Then if the prices are “right,” the market “clears”: the
demand for each good exactly matches the supply. Moreover, the resulting reallo-
cation of goods is optimal (in the above sense); and in large markets, all optimal
outcomes are achievable in this way.
Thus, the unsophisticated but highly complex, involved, and uncertain bar-
tering process is replaced by the price mechanism, which, though a lot more so-
phisticated than barter, is far easier to execute: it requires only that each trader
buys what he likes,5 given his budget.6 Here the complex task is achieving opti-
mality; the simpler tasks are for each trader to decide what he wants, given his
budget; and the decoupler is the price mechanism. And again, the driving force is
individual motivation. Each individual is motivated to “maximize over his budget
set”–sell and buy, at the given market prices, so as to be left with those goods
and services that he most prefers.
4More precisely, no group of traders could have improved the welfare of all its members by
trading within the group only. In economic theory, such outcomes are called core outcomes.
5Unlike barter, where each trader needs some knowledge about the preferences of the traders
with whom he trades, and also about at least some of the others, so that he will know with
whom to trade.
6The proceeds from the sale, at market prices, of the goods that he brought to the market.
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An interesting aspect of this decoupling is that historically, it has emerged by
itself in every reasonably advanced society, without being imposed by any plan-
ning entity. Not only has the price mechanism emerged by itself, but the market
prices themselves also usually emerge by themselves–determined by supply and
demand–without being imposed by planning entities. And when planning enti-
ties do enter the process of price determination, as in the former Soviet Union or
with rent control in various cities, they often wreak havoc, causing shortages and
other distortions.
Whereas this example is related to the previous one (Example ii), they are
not the same. In the previous example, the point was decentralizing the economy,
letting each individual see to himself. In the current example, the point is the
formation of a price system. Logically, the examples are independent; a centrally
planned economy can have a price system, and a decentralized economy can work
on barter.
(iv) Chess. The ideal way to play chess is to plan the entire course of play
from the beginning, taking into account anything the other player might do. In
practice, this is beyond the power of any man or machine. Instead, the players
“evaluate” the situation at each move, using numerical indices for the various
pieces; e.g., 8 for the queen, 5 for a rook, 3 for a bishop or knight, 1 for a pawn.
They also take account of the general characteristics of the position: develop-
ment of the pieces, castling, passed pawns, and so on. Using such criteria, each
player “looks ahead” for a few moves, trying to maximize his valuation of the
position at the end of that period, and taking into account that the other player
is doing likewise. Weaker players often do not look ahead more than a move or
two, and even that only partially. Stronger players may look as much as Þve or
six moves ahead, and sometimes even more; but they, too, do not examine all
possibilities–all “branches of the tree”–in the process. Human players do not
use a precise numerical valuation, but take a generalized view. Chess-playing com-
puter programs7 basically do use a precise numerical valuation function; though
even there, the “depth” of the look-ahead varies, with some branches of the tree
being examined more thoroughly than others.
Here the complex task is planning the whole game beforehand; and the simpler,
decoupled tasks are playing move by move, with a more or less modest look-
ahead. The overall, macroscopic driving force is, of course, the desire to win; but
7Like IBM’s “Deep Blue,” which several years ago defeated World Chess Champion Gary
Kasparov in a tournament (though there have been allegations that “Deep Blue” cheated by
enlisting human aid during the course of play).
7
“microscopically”–at each separate move–the driving force is to maximize the
valuation several moves ahead.
In Examples (ii) and (iii) above, the decoupling is achieved by spreading the
task over many individuals, each with his own motivation. In contrast, in this
case the decoupling is achieved by spreading the task over time. There is a single
overall motivation–winning–which is expressed at each move by looking ahead
a few moves and maximizing valuation.
(v) Solomon’s judgment. Rather than rendering his judgment (1 Kings 3,
16-28), King Solomon could have entered into a complex factual investigation of
the women’s claims. He “decoupled” the process by motivating them unwittingly
to reveal the truth themselves. Here the complex task is determining which woman
is the live baby’s mother; the simpler tasks are for the women to express their
preferences given the judgment; and the driving force is the women’s motherly
love.
(vi) Fair division. This may be achieved by cumbersome methods of direct
measurement. Alternatively, the process may be decoupled by the method of “one
cuts, the other chooses,” which motivates the parties themselves to divide fairly.
(vii) Evolution. Suppose a Creator had wanted to create the living world
as we know it. He could have designed each individual organism separately, to-
gether with the appropriate interactive adaptations. This would have been enor-
mously complex. Alternatively, He could have decoupled the process by means
of evolution–survival of the Þttest–which runs by itself, automatically, with no
need for “hands on” direction. Here the complex task is creating the world; the
decoupled alternative tasks are for each organism–or even each gene–to adapt
to its surroundings; and the driving force is survival of the Þttest.
These examples should give the reader some idea of what we mean by decou-
pling. What we now suggest is that consciousness serves as a decoupler that allows
human beings to perform tasks that otherwise would be unachievable because of
their complexity. Let us illustrate.
(a) Food. The body needs food for energy and other vital purposes. The
process of supplying food may be divided into two parts: (1) before it enters the
mouth, and (2) afterwards. Part 1 consists of triggering the individual to seek
food, and acquiring, preparing, and eating it. Part 2 consists of digesting it, i.e.,
transforming it into a state that the body can use (see Section 1, above).
Both parts are extremely complex, but Part 1 is by far the more so. We must
choose the food to buy, shop for it, store it, clean it, cook it, and serve it. We must
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also choose and buy closets and a refrigerator to store it; sinks to wash it; stoves,
ovens, gas tops, microwaves, pots, pans, cake forms, pie dishes, utensils, mixers,
vegetable peelers and so on to prepare it; plates, bowls, platters, and utensils, to
serve it. We must earn money to buy the food and all the auxiliary items we have
mentioned, and those we have not mentioned. Earning money usually involves
various skills–not the least of them social–which must be acquired.
There is another fundamental difference between the two parts. Part 2 is
“hard-wired”: It works “automatically,” by mechanical, chemical, and electrical
means, with no conscious, voluntary component. Part 1 is precisely the opposite:
all conscious, all volitional. To start with, when the body runs short of the
required nutrients, it must be prompted to eat. Once this is done, the food must
be acquired, prepared, and eaten. Conceivably, parts of the process could be hard-
wired: A gauge could tell the brain when the stomach is empty; the eye and brain
could identify food, then send signals to the hand automatically to take it and
put it in the mouth. But it seems unlikely that acquiring the food and preparing
it, and earning the necessary money, could all be hard-wired.
How, then, does the process work? What drives it?
The answer is simple, even obvious: hunger. And, the other side of the same
coin: enjoyment of food.
Hunger does not mean an empty stomach. An empty stomach by itself will
not prompt us to eat. We need the pain or discomfort of hunger, and/or the
pleasure of food, to make us eat. Pain and pleasure depend on consciousness. If
you are not conscious, you cannot experience pain or pleasure. So consciousness
is an important component of the mechanism that supplies us with nutrients.
Moreover, it decouples the nutritive process into the two parts we have described:
until the food reaches the mouth, and afterwards.
Indeed, it does much, much more: The entire process of acquiring, preparing,
and serving food is decoupled into many small steps. Each step is conscious,
with a well-deÞned goal; it is motivated. Going to market, picking the items to
buy, standing in line at the check-out counter, bringing the items to your car,
unloading, putting in the refrigerator, all the myriad tasks involved in cooking,
all the myriad tasks involved in earning the money with which to buy the food,
all the myriad tasks involved in all stages of the process–all together, and each
one separately–are driven by hunger, through the medium of consciousness; they
are motivated.
More precisely, the experiences of hunger and food enjoyment are the overall,
macroscopic driving forces, like the desire to win in chess (Example iv above). The
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thought process, which is the second component of consciousness (see Section
2, Item viii), translates this into many small tasks–making money, baking a
cake, and so on–each with its own driving force, like valuation-maximizing in
chess. And then volition–the third component of consciousness–comes into play,
enabling the individual actually to carry out these individual tasks.
It is important to note that while “hard-wired” processes like digestion may be
highly complex, they are fairly repetitive. Digestion works on the same materials,
in the same way, every day; there are few, if any, surprises. The processes of food
acquisition and preparation are much less repetitive; they require a good deal
of instantaneous adaptation to various different environments, environments that
may be unfamiliar. Consciousness is particularly important for motivating and
carrying out these non-repetitive tasks.
Finally, we remark that themechanisms provided by nature to facilitate eating–
hunger and the enjoyment of food–may sometimes “misÞre.” It is well known
that severely undernourished people whose hunger leads them to overeat may
well die as a consequence; there are documented cases of people who survived
the concentration camps during the Holocaust, only tragically to die in this way.
Even better known is that the enjoyment of food may cause people to overeat or
to eat foods that are not nutritious. While not immediately fatal like with the
concentration camps, this may nevertheless be detrimental to health; or at least,
serve no useful adaptive purpose.
(b) Sex. Biologists identify two basic drives in living organisms: nourishment
and reproduction.8 What we have said about food applies, mutatis mutandis, also
to sex. It is hunger and the enjoyment of food–not the need for nourishment!–
that makes people eat. Similarly, it is not the desire for offspring that makes
them have sex; it is the sex drive–the enjoyment of sex. Enjoyment is a function
of consciousness. You cannot enjoy if you are not conscious. Many people do
consciously want offspring, but that is not why they have sex.9
As with nourishment, the process of reproduction has several distinct parts:
(1) before the semen enters the woman’s body; (2) conception and pregnancy;
8It is interesting that in several places, the Talmudic literature identiÞes these two basic
drives. In the biblical verse relating how Joseph’s master, Potiphar, “left everything in Joseph’s
hands, except for the bread that he (Potiphar) eats” (Genesis 39, 6), the Midrash takes the
“bread” to mean Potiphar’s wife. And when Jethro’s daughters tell him that “an Egyptian man
saved us,” and Jethro says, “where is he? Call him and let him eat bread” (Exodus 2, 19-20),
the Midrash takes the “bread” to mean the daughters themselves.
9Thus, homosexuals will usually not have relations with persons of the opposite sex. When
they want offspring, they prefer adopting, or artiÞcial insemination.
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and (3) childhood, when the offspring cannot fend for itself. The Þrst two parts
are decoupled by the sex drive. The second part, though highly complex, is hard-
wired; once sex has taken place, there is no conscious intervention until birth.
After birth, parental love takes over; like hunger and the sex drive, this depends
on consciousness. As with food, the Þrst and third parts of the process–which
are not hard-wired–split up into a myriad of distinct small steps, starting with
dating and earning the required money; each is conscious, each has a well-deÞned
goal, each is motivated.
Like with food, the hard-wired part of the process is fairly repetitive, the other
parts not.
Unlike food, sex is programmed to be proßigate. In a single season, a single
ßowering tree produces many hundreds of thousands of blossoms, and billions
of grains of pollen. It is doubtful if even one of these comes to fruition. In
each ejaculation there are hundreds of millions of sperms, at most one of which
is used. Many sexual episodes lead nowhere, many relationships lead nowhere,
many dates lead nowhere. The sex drive leads to many activities that have no
chance of producing offspring: sex with birth control, sex after the reproductive
age, homosexuality, masturbation, oral sex, bestiality, pornography, and so on.
Love and sex play dominant roles in advertising, literature, Þlm, music, painting,
photography, dance, almost all cultural activity. In the case of food, we used the
term “misÞre” to describe situations in which food does not provide nourishment.
In the case of sex, the corresponding situations are so ubiquitous that they must
be considered a part of the process.
(c) Pain. It has long been recognized that pain calls attention to something in
the body having gone wrong, so that it can be attended to. Again, pain depends
on consciousness; if you are not conscious, you cannot experience pain. Machines
cannot suffer.
As before, we have here a decoupling process. Pain motivates the individual to
seek medical or surgical treatment. Unlike with food and sex, though, the effect of
treatment is not entirely automatic; repeated intervention may be required. Pain
decouples the treatment process into many distinct small steps, motivating the
individual at each step to do what is required in order to alleviate his condition.
It, too, may “misÞre,” as when a medical or surgical treatment causes more pain
than what the patient can suffer.
To summarize: Consciousness enables the decoupling of highly complex,
non-repetitive tasks into many simpler tasks, mainly through the element of mo-
tivation.
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4. How
This is the shortest of our sections: We have little to contribute on this score,
other than to say that the neurological phenomena that have been observed to be
associated with consciousness do not explain how it works; the “how” remains a
deep mystery.
One last remark is worth making. “How” questions are usually answered
by analogy with something else, with which we are familiar. For example, the
workings of the circulatory system are explained by analogy with plumbing. But
consciousness is unique; there is nothing else in the world that is even remotely
like it. Since there is nothing like it, what analogy can we use to explain it? And
if not by analogy, how else can it be “explained?”
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