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In two minds
| With 'The Conscious Mind: In Search of a Fundamental
Theory' David Chalmers
introduced a radical new element into the debate about consciousness when it was perhaps in danger of
subsiding into unproductive trench warfare. Many found some force in
his arguments; others have questioned whether they are particularly new
or effective, but even if you don't agree with him,
the energising effect of his intervention can still be welcomed.
Chalmers believes (and of course he's not alone in this
respect) that there are two
problems of consciousness. One is to do with how sensory inputs get
processed and turned into appropriate action; the other is the
problem of
qualia
- why is all
that processing accompanied by sensations, and what are these vivid
sensations, anyway? He calls the first the 'easy' problem and
the second, which is the real focus of his attention, the 'hard'
problem. Chalmers is careful to explain that he doesn't mean
the 'easy' problem is trivial, just nothing like as
mind-boggling as qualia, the redness of red, the ineffably
subjective aspect of experience.
The real
point, in any case, is his view of the 'hard' problem, and here
the unusual thing about Chalmers' theory is the extent to which he
wants to take on two views which are normally seen as opposed. He
wants behaviour to be explainable in terms of a materialist,
functionalist theory, operating within the normal laws of physics:
in fact, he ends up seeing no particular barrier to the successful
creation of consciousness in a computer. But he also wants
qualia which remain mysterious in some respects and which appear to
be have no causal effects. He doesn't quite commit himself on this
last point: the causal question remains open (qualia might
over-determine
events,
for example, having a causal influence which is
always in the shadow of similar influences
from straightforward physical causes) and he does not sign up
explicitly to epiphenomenalism (the view that our thoughts actually
have no influence on our actions) - but he thinks the current arguments for the
opposite views are faulty. All the words in the mental vocabulary, on
his view, acquire two senses: there is psychological
pain, for example, which plays a full normal part in the chain of
cause and effect, and affects our behaviour: and then there is
phenomenal pain, which does not determine our actions, but
which actually, you know, hurts . |
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Chalmers is surely
a dualist, because he believes in two kinds of fundamental stuff,
and he is
an epiphenomenalist, because he
believes our thoughts and feelings have no real influence on the
world. Neither of these positions makes sense. The book pulls its punches in these kinds of
areas. He says he does not describe his
view as epiphenomenalism, but that the alternatives to epiphenomenalism are
wrong. Now if you believe the negation of a view is wrong, you have to
believe the view is right, don't you? And what is this 'causal
over-determination' business? So an event is caused by some physical
prior event, and also caused by the qualia - but it
would have happened just the same way if the qualia weren't there?
Chalmers says there's no proof this is true, but no real argument to
disprove it, either. How about Occam's Razor? A causal force
which makes no difference to events is a redundant entity which
ought to be excised from the theory. Otherwise we might as
well add undetectable angels to the theory - hey, you
can't prove they don't exist, because they wouldn't make any
difference to anything anyway.
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This aggressive attitude is out of place. I think you have to take on board that Chalmers is
quite honest about not presenting a final answer to
everything. What he's about is taking the problems
seriously. This has a certain resonance with many people. There
was a gung-ho era of artificial intelligence when many people just
ignored the philosophical problems, but by the time Chalmers
published "The Conscious Mind" I think more were
prepared to admit that maybe the problem of qualia was more
substantial than they thought. Chalmers seemed to be speaking their
language. Of course, this may be irritating to philosophers who
may feel they had been going on about qualia for years without
getting much attention. It irritates some of the philosophers
even more (not necessarily a bad thing) when Chalmers adopts (or
fails definitely to reject, anyway) views like epiphenomenalism,
which they mostly regard as naive. But you really
can't say Chalmers is philosophically naive - he has an
impressibve command of technical philosophical issues and
handles them with great aplomb. |
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Oh, yes. All those pages of stuff about
supervenience, for example.
That's
exactly what I hate about philosophy
- the gratuitous elaboration of pointless technical issues. I
mean, even if we got all that stuff straight, it wouldn't help one
iota. We could spend years discussing whether, say, the driving of a
car down the road supervenes under the
laws of physics on the spark in the cylinder at time
t, or under some conjunction of laws of
modal counterfactuals, yet to be specified, with second-order laws
of pragmatic engineering theory. Or some load of old
tripe like that. It wouldn't tell us how the engine
works - but that's what we
want to know, and the same goes for the
mind.
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Well, I'm sorry but you have to be prepared to
take on some new and slightly demanding concepts if we're
going to get anywhere. We can't get very far with naive ideas of
cause and effect: the notion of supervenience gives us a way to
unravel the issues and tackle them separately. I know this is
difficult stuff to get to grips with, but we're talking about
difficult issues here. You just want the answer to be
easy.
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Easy! It's Chalmers who ignores the
real problems. Look at dualism. It's only worth accepting a
second kind of stuff if it makes things easier to explain. If we
could solve the problem of qualia by assuming they live in a
different world, there might be some point. But we can't:
they're just as hard to explain in a dualist world as they were in a
monist, materialist one, and on top of
that you have to explain how the two worlds relate to each other.
Chalmers ends up with 'bridging principles', which specify that
phenomenal states always correspond with psychological ones. This
sounds like Leibniz's pre-established harmony between the spirit and
body, but at least Leibniz had God to arrange things for him!
Chalmers
actually has no way of knowing whether psychological
and phenomenal states correspond, because he only ever experiences
one of them (which one depends on whether it's Phenomenal Chalmers
or Psychological Chalmers we're talking about, I suppose). The final
irony is that it's Psychological Chalmers who writes the books,
because that's a physical, cause-and-effect matter: but his reasons
for writing about qualia can't be anything to do with qualia
themselves, because he never experiences them - only Phenomenal
Chalmers does that... And we haven't even touched on the stuff about
how thermostats feel, and the mysterious appeal of
panpsychism. But really, the worst of it is that the problem
he's inviting people to 'take seriously' is the wrong one. The whole 'problem of qualia' is a
delusion.
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On the contrary, it's the whole point. You should read
less Dennett and more by other people. Incidentally, it must be
in Chalmers' favour that neither
Dennett nor his
arch-enemy
Searle
has any
time at all for Chalmers. He must be doing something right to
attract opposition like that from both extremes, don't you
think?
Two points, though.
First, if we want to make any progress at all, it's going to involve
contemplating some weird-looking ideas. All the mainstream ones
have been done already. Chalmers is all about opening up
possibilities, not presenting a cast-iron finished theory. Second,
you're talking as if Chalmers took up dualism for no reason, but in
fact he gives a whole series of arguments which explain why we're
forced to that conclusion.
Argument 1: The
logical possibility of zombies, people exactly like us but
with no qualia. This is the main one, which puts in its
simplest form Chalmers' underlying point of view that qualia
are separable from the normal physical account of the world,
and so just must be something different..
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Argument 2: The
Inverted Spectrum. An old classic, which relies on the
same basic insight as the first argument, ie that you could
change the qualia without changing anything else. Arguments
along these lines have been elaborated to the nth degree
elsewhere, but Chalmers' version is pretty
clear.
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Argument 3: From
epistemological asymmetry. Qualia just don't look the same
from the inside. When we examine the biology of our leg, it
isn't essentially different from examining someone else's: but
when we examine our own sensations, it bears no resemblance to
observing the sensations of others.
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Argument 4: The
knowledge argument. Our old friend Mary the colour scientist .
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Argument 5: The
absence of analysis. This is simply a matter of putting the
onus on the opposition to give an account of how qualia could
possibly be physical.
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The main
point of the main argument, very briefly, is that we can easily
imagine a 'zombie': a person who has all the psychological stuff
going on, but no subjective experience. At the very least, it's
logically possible that there should be such people. As a result,
you cannot just identify the physical workings of the brain, the
psychological aspect, with the subjective experience, the phenomenal
aspect. I have to say I think this is essentially
correct. |
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There's no way we can know
whether something is logically possible unless we understand what
we're talking about. We need to know what phenomenal consciousness
is before we can decide whether zombies
without it are possible. Chalmers assumes it's obvious that
phenomenal experience isn't physical, and hence it's obvious we
could have zombies. But this just begs the question. I assume
phenomenal experience is a physical process, so it's obvious to me
that there couldn't, logically, be a person who was physically
identical to me without them having my experiences. Look at it
this way. If Chalmers didn't understand physics, he would probably
find it easy to imagine that the molecules inside him could move
around faster without his temperature going up. But when he
understands what temperature really is, he can see that it was
logically impossible after all.
Chalmers is really presenting intuitions disguised as arguments
- alright, he's not alone in that, but they're
dodgy intuitions, too. Look at that stuff about
information. According to Chalmers, anything with a shape or marks on it, in
fact anything at all, is covered in information - information
about itself and how it got the way it is. We can speculate that any
kind of information might give rise to consciousness: maybe
even thermostats have a dim phenomenal life similar to just
seeing different shades of grey. Since, on Chalmers' interpretation of
information, everything is covered in it, it follows that everything
is in some degree conscious. The result? Panpsychism, a
third untenable position... |
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Chalmers
does not actually endorse panpsychism, he just speculates about it.
Do you think the idea is uninteresting ? Can you not accept that if
philosophers aren't allowed to speculate, they're not going to
achieve very much? |
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And then,
a chapter about the correct interpretation of quantum physics!
What's that about, then? |
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Chalmers sees a kind of harmony between his views and one of the
possible interpretations of quantum theory. I have no idea whether he's
on to anything, but this sort of linkage is potentially valuable, especially
to philosophy,which has tended to cut itself off from
contemporary science. But the point is, all these latter
speculations are just that - interesting, stimulating speculations.
Chalmers never pretends they're anything else. The point of the book
is to get people to take qualia seriously. That's a good, well-founded project and I
think even you would have to admit that the book has succeeded
to a remarkable degree. |
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If
you ask me, Chalmers basically gives the whole thing away early on,
when he says that another way of looking at the
psychological/phenomenal distinction is to see them as the
third-person and first-person views. Wouldn't common sense
suggest that this is just a case of a single phenomenon looked at
from two different points of view? It seems the obvious conclusion
to me.
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But if the mind-body problem has taught us
anything, it is that nothing about consciousness is obvious, and
that one person's obvious truth is another person's
absurdity... |
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Read: |
"The
Conscious Mind: In Search of a Fundamental
Theory"
The main statement of Chalmers'
ideas A wide-ranging survey of arguments and
possible positions, but always informed by the author's
own search for the answers. Some passages
feature technical philosophy, but an interesting
read for anyone, and undoubtedly one of the indispensable
books in the field. |
"Explaining Consciousness: The Hard
Problem"
Collection of pieces by many eminent
figures responding to Chalmers from various points of view.
Possibly an easier introduction to Chalmers's
views. |
"The Mystery of
Consciousness" Collection
by Searle, including a vigorous attack on, and entertainingly
combative exchange with,
Chalmers. |
Some Links:
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fragments of
consciousness
: David Chalmers' blog, set up in January 2005. Mainly aimed at
those with some academic background in philosophy rather than the general reader.
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Homepage: An extensive site, with large
amounts of interesting material - a great resource .
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Review in
Psyche:
'I don't think this is a
bad book, but...' |
Facing up to the problem of
Consciousness - An early paper |
Chalmers on 'The Matrix'
- Plug this one into your head and see
where it takes you... |
General Links
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