Cottrell, A.,Wake Forest University, Dept. of Economics, Box 7505, Winston-Salem NC 27109, USAcottrell@wfu.edu
The 'real' issue concerns the status of qualia, that is, the subjective sensory states into which we are thrown when (say) looking at a yellow leaf, hearing a musical chord, sniffing a camembert, or running our fingers over a piece of sandpaper. Is it possible to provide a satisfactory account of such states using only the resources of a materialist functionalism? Or is it the case -- as it has seemed to many, and as it seems to David Chalmers -- that once we have said all there is to say about the physical basis of, and the functional role of, such states, there remains an uneliminable residue: the brute qualitative matter of 'what it is like' to sniff the camembert? Since it is extraordinarily hard to tackle this question head-on, we seek the leverage afforded by the notion of the philosopher's zombie, the point being that if we have a coherent intuition to the effect that there is indeed such a residue, then we ought to be able to conceive of the zombie. Just subtract the residue while leaving all the physical/functional stuff in place. Conversely, if it transpires that the notion of the philosopher's zombie breaks down under stress, this would seem to indicate that the intuition of the ineliminable residue is itself problematic.
The 'remedy' for a belief in zombies is the sort of Dennettian exercise
in imagination proposed in this paper. One must be forced to recognize
the huge gulf between the simple informational economies of the thermostat,
and even the PC, and the amazingly subtle and layered informational economy
of a normal human being. Taking the PC, or the severely degraded registrations
of actual blindsight victims, as the model, one may fool oneself into thinking
one has imagined something when one has not really confronted its detailed
implications. This piece will have accomplished its aim if it encourages
a few readers to take the latter possibility more seriously than hitherto.
The time taken to react voluntarily to a stimulus is far longer than
can be accounted for by ordinary processes of nerve conduction and synaptic
delay, and varies unpredictably from trial to trial. Though random, the
distribution of reaction times usually follows a relatively simple law,
which in turn can be explained by the LATER model, in which a decision
signal, representing belief in the existence of the target, rises in response
to incoming sensory evidence from an initial value to a criterion level
at which action is initiated. But the rate of rise fluctuates randomly
from trial, to an extent that cannot be explained by sensory noise at the
input. These conclusions, confirmed by recording from neurons in the frontal
eye fields, suggest that the randomness of reaction time is due to a deliberate,
gratuitous, neural process which confers certain biological advantages
as well as having implications for general ideas about the nature of ‘free
will’.
Esfeld, M., University of Konstanz, Center for Philosophy of Science, PO Box 5560 D24, D-78457 Konstanz, Germany Michael.Esfeld@uni-konstanz.de
This paper attempts to build a bridge between the interpretation of
quantum theory and the philosophy of mind. In contrast to other such attempts,
the bridge which this paper suggests does not consist in extending features
of quantum theory to the philosophy of mind. The argument of this paper
is that the discussion about a revision of the Cartesian tradition in current
philosophy of mind is relevant to the interpretation of quantum theory:
taking this discussion into account sharpens up the task for the interpretation
of quantum physics as far as the scope of what is known as quantum holism
is concerned. In particular, considering this discussion makes out a strong
case against the interpretation that considers quantum holism to be universal
in the physical realm.
Horst, S., Department of Philosophy, Wesleyan University, Middletown CT 06459, USA. shorst@wesleyan.edu
Chalmers and others have argued that physicalist microexplanation is
incapable of solving the 'hard problem' of consciousness. This article
examines whether evolutionary accounts of the mind, such as those developed
by Millikan, Dretske and Flanagan, can add anything to make up for the
possible short falls of more reductionist accounts. I argue that they cannot,
because evolutionary accounts explain by appeal to a selectional history
that only comes into the picture if consciousness can first arise due to
spontaneous mutation in some individual organism, and explaining this emergence
of consciousness from DNA and embryology calls for precisely the kind of
structurally-based supervenience account that Chalmers et al. have objected
to. Not only does an evolutionary account not succeed where a reductionist
account fails; the evolutionary account presupposes the possibility of
a reductionist account.
Stanley, R.P., Department of Mathematics 2-375, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
We define qualia space Q to be the space of all possible conscious experience.
For simplicity we restrict ourselves to perceptual experience only, though
other kinds of experience could also be considered. Qualia space is a highly
idealized concept that unifies the perceptual experience of all possible
brains. We argue that Q is a closed pointed cone in an infinite-dimensional
separable real topological vector space. This quite technical structure
can be explained for the most part in a simple, intuitive way. The structure
of qualia space allows us to consider and even answer in a precise way
such questions as: Is there a continuous path from the sensation of blue
to the sensation of pain? Once we fix a desired accuracy of approximation,
do there exist finitely many perceptual experiences such that any possible
perceptual experience is approximately equal to one of them? What should
be meant by 'fundamentally different' perceptual experiences? There is
the possibility of additional structure, such as a Hilbert space structure
on the vector space in which Q is embedded.
Stapp, H.P., Lawrence Berkeley National Laboratory, University of California, Berkeley CA 94720, USA
Replies are given to arguments advanced in this journal that claim to
show that it is to nonlinear classical mechanics rather than quantum mechanics
that one must look for the physical underpinnings of consciousness.
Warfield, T.A., Philosophy Department, The University of Notre Dame, Notre Dame, Indiana 46556, USA. warfield.3@nd.edu
In recent years, the primary focus of many philosophers of mind (though
not Fodor) has shifted to consciousness. And a growing number of philosophers,
attempting to exploit some of the advances of the previous decade's work
on intentionality, are advocating representational theories of consciousness.
Representationalists have spent much time defending their characteristic
thesis (RT) and have devoted much effort to some of the peculiar problems
facing theories of consciousness (examples: inverted spectrum, absent qualia).
They have expended precious little energy answering more basic questions
like 'What makes a conscious state a conscious state?', 'What conditions
are necessary and sufficient for consciousness?', and 'What can be said
on behalf of the naturalization of consciousness?' It is my suspicion,
fuelled by the remarks of Armstrong, Lycan and Levine quoted in the paper,
that representationalists have thought that these problems are solved (or
at least reduced to the corresponding problems of intentionality) if RT
is correct. But this, I have argued, is a mistake. It's time for representationalists
to address these issues
Worden, R.P., Charteris Ltd., 6 Kinghorn Street, London EC1A 7HT, UK rworden@dial.pipex.com
I propose that neural cognition is supported by non-neural storage of
a 3-D model of local space, used in the planning of movements. Information
is stored in wave-like excitations which couple to neurons in the thalamus,
with the wave-vectors of excitations representing spatial positions. This
hybrid of neural and non-neural cognition may have fitness advantages over
any purely neural mechanism -- in information capacity, geometric accuracy,
and fast selective retrieval. The wave excitations may be sustained on
a Bose-condensed state of some excitation in the brain, by a mechanism
like those investigated by Fröhlich, Umezawa, Vitiello and others.
These states, being frictionless, can store information indefinitely at
low energy levels, insulated from thermal noise, so are an ideal substrate
for memory. If a Bose-condensed state is a 3-D representation of local
reality, it may be the basis of phenomenal consciousness (which is also
a model of local reality). The resulting theory of consciousness is highly
constrained, and agrees well with the main properties of conscious experience.
In this account, consciousness arises from a very simple state of matter,
rather than from complexity; and it evolved to meet one of the strongest
selection pressures on the brain.
de Quincey, C., Institute of Noetic Sciences, 475 Gate Five Road, Suite 300, Sausalito CA 94965, USA. cdeq@noetic.org
Every worldview expresses some deep truth -- and is in error only if it claims possession of the whole truth. The most compelling attraction of the worldview so passionately presented in David Ray Griffin's latest book is that it makes so much sense -- hard core commonsense. It is inclusive of matter and mind, of determinism and freedom, of mechanism and creativity, and it offers a way of reconciling the apparently conflicting worldviews of materialism, dualism and idealism.