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are good for many purposes.) But our software mind
has lost its body---or had it replaced by an elaborate
prosthesis. What experience could be more shatter-
ing? What loss could be harder to bear? (Some losses,
granted, but not many.) What gives us the right to
in ict such cr uel mental pain on a conscious being?
In fact, what gives us the right to create such a
being and treat it like a tool to begin with? Wherever
you stand on the religious or ethical spectrum, you
had better be prepared to tread carefully once you
have created consciousness in the laboratory.
The Cognitivists Best Argument
But not so fast! say the cognitivists. Perhaps it seems
arbitrary and absurd to assert that a conscious mind
can be created if certain simple instructions are exe-
cuted very fast; yet doesn t it also seem arbitrary and
absurd to claim that you can produce a conscious
mind by gathering together lots of neurons?
The cognitivist response to my simple thought
experiment ("Imagine you re a computer") might r un
like this, to judge from a recent book by a leading cog-
nitivist philosopher, Daniel C. Dennett. Your mind
is conscious; yet it s built out of huge numbers of tiny
unconscious elements. There are no raw materials for
creating consciousness except unconscious ones.
Now, compare a neuron and a yeast cell. "A hun-
dred kilos of yeast does not wonder about Braque,"
writes Dennett, "... but you do, and you are made of
parts that are fundamentally the same sort of thing as
those yeast cells, only with di erent tasks to perform."
Many neurons add up to a brain, but many yeast cells
don t, because neurons and yeast cells have different
tasks to perform. They are programmed di erently.
In short: if we gather huge numbers of unconscious
elements together in the right way and give them the
right tasks to perform, then at some point, something
happens, and consciousness emerges. That s how your
brain works. Note that neurons work as the raw mate-
rial, but yeast cells don t, because neurons have the
right tasks to perform. So why can t we do the same
thing using software elements as raw materials---so
long as we give them the right tasks to perform? Why
shouldn t something happen, and yield a conscious
mind built out of software?
Here is the problem. Neurons and yeast cells don t
merely have "di erent tasks to perform." They perform
di erently because they are chemically di erent.
One water molecule isn t wet; two aren t; three
aren t; 100 aren t; but at some point we cross a thresh-
old, something happens, and the result is a drop of
water. But this trick only works because of the chemistry
and physics of water molecules! It won t work with just
any kind of molecule. Nor can you take just any kind of
molecule, give it the right "tasks to perform," and make
it a t raw material for producing water.
The fact is that the conscious mind emerges when
we ve collected many neurons together, not many
doughnuts or low-level computer instr uctions. Why
should the trick work when I substitute simple com-
puter instructions for neurons? Of course, it might
work. But there isn t any reason to believe it would.
My fellow anticognitivist John Searle made essen-
tially this argument in a paper that referred to the
"causal properties" of the brain. His opponents
mocked it as reactionary stu . They asserted that
since Searle is unable to say just how these "causal
properties" work, his argument is null and void.
Which is nonsense again. I don t need to know any-
thing at all about water molecules to realize that large
groups of them yield water, whereas large groups of
krypton atoms don t.
Why the Cognitive Spectrum Is More
Exciting than Consciousness
To say that building a useful conscious mind is highly
unlikely is not to say that AI has nothing worth doing.
Consciousness has been a "mystery" (as Turing called
it) for thousands of years, but the mind holds other
mysteries, too. Creativity is one of the most impor-
tant; it s a brick wall that psychology and philosophy
have been banging their heads against for a long time.
Why should two people who seem roughly equal in
competence and intelligence di er dramatically in cre-
ativity? It s widely agreed that discovering new analo-
gies is the root (or one root) of creativity. But how are
new analogies discovered? We don t know. In his 1983
classic The Modularity of Mind, Jerry Fodor wrote,
"It is striking that, while everybody thinks analogi-
cal reasoning is an important ingredient in all sorts of
cognitive achievements that we prize, nobody knows
anything about how it works."
Furthermore, to speak of the mystery of conscious-
ness makes consciousness sound like an all-or-nothing
proposition. But how do we explain the di erent kinds
of consciousness we experience? "Ordinary" conscious-
ness is di erent from your "drifting" state when you
are about to fall asleep and you register external events
only vaguely. Both are di erent from hallucination as
induced by drugs, mental illness---or life. We halluci-
nate every day, when we fall asleep and dream.
And how do we explain the di erence between
a child s consciousness and an adult s? Or the dif-
ferences between child-style and adult-style think-
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