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Hollywood producers are not the only ones who think that
zombies exist. Some philosophers think
that too. But there is a tiny difference. The philosophers' zombie is not an
inelegantly walking corpse that stinks (like in the movie "Dawn of the Dead")
and makes strange sounds, but a creature that is very similar to a normal human
being. In fact, there is only one thing that makes a difference between an
ordinary human being and a zombie - zombie is not a conscious being. In other
words, zombie is an imaginary being that looks like a human being, talks like a
human being, smells like a human being, passes the Turing test like an ordinary
human being... but it doesn't have a conscious experience like a human being
does. Zombie is lacking a subjective feeling of what it is like to be a zombie
- there is nobody at home. Can you imagine that your wife or girlfriend is a
zombie? Hmm, maybe that is not so hard to imagine. But can you imagine that
your friends are zombies? Or, if we want to be radical, that all human beings are
zombies? Including you? Are those philosophers who think that a conscious
experience is what makes a difference between human beings and zombies - zombies
as well? Well, why not? Dennett thinks that it is acceptable to say: "We're all
zombies". (Dennett 1991: 406). How is it possible for a serious philosopher to claim
something like that?
The zombie problem is a
philosophical problem and hints to it can be found even in the Putnam's
critique of the behavioral theory of mind. In his argument about the
possibility of a Superspartan, an
imaginary being that doesn't behave as if it were in pain, but feels an intense
pain, Putnam revealed the flaws in the behavioral theory of mind (Putnam 1961:
29-34). Something quite different would be a Superactor, an imaginary being that successfully acts as if it felt
an enormous pain, but feels no pain at all. That Superactor is a hint of a zombie, a hint of a being that is, in an
extreme case, just "... something physically identical to me, but which has no
conscious experience - all is dark inside". (Chalmers 1996: 96). Even those arguments
of Putnam's suggest that there is something that is not visible from the
outside, from the third-person approach. That "invisible thing", or "special ingredient"
as Dennett calls it, is the main point of a zombie thought experiment.
Consciousness, as we commonly think of it, is something interior and private.
Some philosophers find it very plausible to think that it is possible to
conceive a "human being" that lacks those interior and private conscious
experiences. Such a being they name zombie. We can know many things about zombies:
their way of doing things, their functioning in everyday situations, even their
chemical structure... but we cannot know whether there is anybody at home. So,
they think, zombies are in all respects like human beings, with one slightly
difference: they are unconscious.
Philosophical considerations about
the possibility of zombies make Dennett feel ashamed of being a philosopher. He
says: "...it is an embarrassment to our discipline that what is widely regarded among
philosophers as a major theoretical controversy should come down to whether or
not zombies (philosopher's zombies) are possible/conceivable" (Dennett 1995:
177). In his Consciousness Explained
Dennett writes: "(It's hard for me to keep a straight face through all this,
but since some very serious philosophers take the zombie problem seriously, I
feel obliged to reciprocate.)" (Dennett 1991: 95). Hence, for Dennett, an
intuition about the possibility of zombies is not a good starting point of the
philosophy of consciousness. Why not? Because if there is a possibility of
zombies, than it is impossible to approach consciousness from the third-person's
point of view. And in that case, consciousness remains a mystery, something
that cannot be an object of science, because all science is made from the third-person's
point of view. It is unacceptable for Dennett to admit that consciousness is a
mystery beyond science. And philosophy that admits that consciousness is a
mystery is an obstacle to the science of consciousness. If zombies are
possible, than there is no public criterion that can help us in making a
difference between a zombie and a conscious human being. And epiphenomenalism
and dualism are not scientifically fruitful.
However, there are still many
philosophers that seriously consider the problem of zombies. Dennett calls them
Zombists (John Searle, David Chalmers, Joseph Levine, Colin McGinn, and Thomas
Nagel are mentioned). The zombists are "...united in the conviction that there is a real difference between a conscious
person and a perfect zombie - let's call that intuition the Zombic Hunch - leading them to the
thesis of Zombism: that the fundamental flaw in any mechanistic
theory of consciousness is that it cannot account for this important difference"
(Dennett 2005:14). That hunch suggests that consciousness or conscious
experience is something in addition to
or something beside the process that
happens in brain. That kind of thing cannot be fully explained by explaining
the mechanisms of consciousness. In order to show that the Zombic hunch is not
a good way of thinking about consciousness, Dennett must find other intuitions,
which offer a better way of thinking about consciousness.
The question is: How can we dispel
the magic of the Zombic hunch? How can we escape such a strong intuition? Is
there a stronger intuition? Dennett admits that he is also visited by the
Zombic hunch, but he doesn't credit it
as the Zombists do (Dennett 2005: 14). On the other hand, he credits an intuition
that I will call the Zimboic Hunch.
The Zombie thought experiment is all
about a possible or conceivable situation. For Dennett, thought experiments in
general are nothing but intuition pumps, since they cannot be used as a method
of verification of the validity of our hypothesis (as it is possible in
scientific experiments). "They are more art than science." (Dennett 1991: 440).
The main defectiveness of thought experiments is that "...people don't actually
imagine the case in the detail that it requires" (Dennett 1991: 436). But details
do matter. Complexity does matter. "The most influential thought experiments in
recent philosophy of mind have all involved inviting the audience to imagine
some specially contrived or stipulated state of affairs, and then - without
properly checking to see if this feat of imagination has actually been
accomplished - inviting the audience to "notice" various consequences in the
fantasy" (Dennett 1991: 282). Details are important and "the force of such an
argument depends critically on how high one's standards of conception are"
(Dennett 1991: 282). When a Zombist claims that he can conceive a zombie, we
have to ask him: Oh, really? "Can you really imagine a zombie?" (Dennett 1991:
282). Can you really imagine a being that is indistinguishable from a normal
human being, but lacks conscious experience? I can't.
In order to break the zombie spell,
Dennett introduces the concept of zimbo.
Everyone who thinks that a zombie is possible must also admit that a zimbo is
possible. "A zimbo is a zombie that, as a result of self-monitoring, has
internal (but unconscious) higher-order informational states that are about its
other, lower-order informational states... A zimbo is just a zombie that is
behaviorally complex; thanks to a control system that permits recursive
self-representation". (Dennett 1991:310). Zimbo can successfully pass the
Turing test. Zimbo has an inner life. Zimbo has a unique point of view. However,
zimbo is just a complex zombie that, owing to its complexity, has beliefs about
beliefs and beliefs about its other states. "What zimboes have that zombies do
not is a sophisticated internal mechanism - they are functionally complex".
(Polger 2000: 268). Zimbo is just a zombie that believes that it is conscious
or that it has conscious states.
Dennett thinks that the human being
is a zimbo that: "...would (unconsciously) believe that it was in various
mental states... It would be the 'victim' of the benign user illusion of its
own virtual machine!" (Dennett 1991: 311). If human beings are zimboes, that is
a special kind of zombies, then Dennett's pronouncement that "We're all zombies"
can be seen in a different light. What Dennett wants to say is that, in spite
of the fact that we are not conscious (at least not in a way we have
thought we are), we truly believe
that we are.
Dennett has a Zimboic Hunch: the
hunch that human beings only believe that they are conscious. It is not
that human beings don't have the belief that they are conscious but rather that
the belief is all there is. The conscious experiences themselves are missing.
There is no consciousness besides the
belief that there is consciousness. The consciousness itself is missing. Why does
Dennett think that this is a good way to build the theory of consciousness?
Let's see the other side. Zombists
speak about the four levels of data that the theory of consciousness must take
into consideration:
(a) "conscious
experiences themselves";
(b) beliefs about these
experiences;
(c) "verbal judgments"
expressing those beliefs
(d) utterances of one
sort or another (Dennett 2005:44)
For the Zombists, the primary data
to which a theory of consciousnesses must answer are the "conscious experiences
themselves". Dennett disagrees. He thinks that it is enough to stop at (b), namely
the beliefs about these conscious experiences, i.e. he claims that such beliefs
are the primary data of an adequate theory of consciousness. His explanation of
this conclusion is: "If you have conscious experiences you don't believe you
have - those extra conscious experiences are just as inaccessible to you as to
the external observers. So a first person approach garners you no more usable
data than heterophenomenology does... if you believe you have conscious
experiences that you don't in fact have - then it is your beliefs that we need
to explain, not the nonexistent experiences". (Dennett 2005: 45). In other
words, if we explain the beliefs about the conscious experiences, we have
explained everything that could be explained.
However, we don't have to explain
something that doesn't exist (conscious experiences themselves). If we explain
those false beliefs about consciousness, we have done the job. Conscious
experiences don't exist beside those beliefs about them. "The Copernicans
thought that they did not have to explain the sun's motion, because it was
enough to explain why the sun was believed
to move". (Rorty 1993: 184) The same is valid for the beliefs that we have
conscious experiences. We are the victims of a false belief that we are
conscious. Just like the zimboes. Therefore, it is plausible to say that we are
all zimboes, a kind of complex zombies.
Why does Dennett find it plausible?
This way of thinking about consciousness excludes the possibility of thinking
about consciousness as some "special ingredient" (zombies don't have it!) that
can be found in addition to the existing functional role of the human brain. In
other words, if a being is functionally identical to the conscious being, then
that being is also conscious. That is the Dennett's way of demystifying
consciousness. And if consciousness is something like what Dennett thinks it
is, than it can be an object of scientific investigation.
If you want to believe that all
human beings are zombies, you have to agree with Dennett on the following:
-
There
is no conscious experience if there is no belief that there is a conscious experience.
-
Conscious
experiences about which there is no belief are not accessible to us.
-
Conscious
experiences themselves are not directly accessible to us. (There is a mediator
- a belief).
-
If
we don't have a direct access to our conscious experiences, then it is
acceptable to claim that there are no conscious experiences that exist
independently of the belief that there are conscious experiences.
-
If
there are no conscious experiences without the belief that there are
conscious experiences, then it is acceptable to assert that they are one
and the same thing, i.e. conscious experiences = beliefs that there are conscious experiences
-
If
conscious experiences are the same thing as beliefs that there are
conscious experiences, then there is no need to talk about consciousness
as some "special ingredient" that goes in addition to those beliefs.
-
So,
there is no need for zombies. No need to credit the zombic hunch.
What is then left of our zombic
hunch? Is it still as convincing and obvious as it was before? Or has Dennett
really managed to dispel its magic? Is the zimboic hunch a more plausible
intuition than the zombic hunch? For the rest of us, the question that remains
is the following: What is it like to be a zimbo? Well, we can tell stories
about our inner world, even stories about our consciousness. But beside these stories
- is there anything left?
References:
Block, Ned (1980) (ed.) Readings in
Philosophy of Psychology. Vol. 1, Cambridge:
Harvard University Press.
Chalmers, David (1996) The
Conscious Mind. Oxford: Oxford University Press.
Dahlbom, Bo (1993) (ed.) Dennett
and His Critics. Cambridge:
Blackwell Publishers: 184-202.
Dennett, Daniel C. (1991) Consciousness
Explained. London:
Penguin Books, 1993.
Dennett,
Daniel C. (1995) The Unimagined Preposterousness of Zombies: Commentary on
Moody, Flanagan, and Polger in Dennett (1998): 171-177.
Dennett, Daniel C. (1998)
Brainchildren: Essays on Designing Minds. Cambridge, MA:
The MIT Press.
Dennett, Daniel C. (1999) The
Zombic Hunch: Extinction of an Intuition? in Dennett (2005): 1-23.
Dennett, Daniel C. (2005) Sweet Dreams. Philosophical Obstacles to a Science of
Consciousness.
Cambridge:
MIT Press.
Polger,
Thomas W. (2000) Zombies Explained in
Ross, Brook and Thompson (2000): 259-286.
Putnam,
Hilary (1961) Brains and Behavior in Block (1980): 24-36.
Rorty, Richard (1993) Holism,
Intrinsicality, and the Ambition of Transcendence in Dahlbom (1993):
184-202.
Ross Don, Brook Andrew, Thompson
David (Eds.) (2000) Dennett's
Philosophy: A Comprehensive Assessment. Cambridge, MA:
The MIT Press.
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