four component bases as DNA (adenine, guanine, thymine, and cytosine) in
some very different global structure that did not allow self-replication would
not be judged to be alive by such biological criteria, yet another object contain-
ing very different components in some analogous arrangement that allowed for
self-replication might be. Needless to say, such an analysis is a long way off in
the case of consciousness.
Notes
- The reader is warned not to confuse intentionality with the concept of ‘‘intention’’ in ordinary
language. Your intentions have intentionality in the sense that they may refer to things other
than themselves—for example, your intention to feed your cat refers to your cat, its food, and
yourself—but no more so than other mental states you might have, such as beliefs, desires, per-
ceptions, and pains. The philosophical literature on the nature of intentionality is complex and
extensive. The interested reader is referred to Bechtel (1988) for an overview of this topic. - One might thin kthat if white and blac kwere reversed, certain reflexive behaviors to light would
somehow betray the difference. This is not necessarily the case, however. Whereas you would
squint your eyes when you experienced intense brightness in response to bright sunlight, I
would also squint my eyes in response to large amounts of sunlight. The only difference is that
my experience of brightness under these conditions would be the same as your experience of
darkness. It sounds strange, but I believe it would all work out properly. - One could object that the only thing that differentiates M and L cones is the pigment that they
contain, so people with both forms of red-green color blindness would actually be normal tri-
chromats rather than red-green-reversed ones. There are two other ways in which M and L cones
might be differentiated, however. First, if the connections of M and L cones to other cells of the
visual system are not completely symmetrical, they can be differentiated by these connections
independently of their pigments. Second, they may be differentiable by their relation to the
genetic codes that produced them.
References
Armstrong, D. M. (1968).A materialist theory of the mind. London: Routledge & Kegan Paul.
Baars, B. (1988).A cognitive theory of consciousness.Cambridge,England:CambridgeUniversity
Press.
Churchland, P. M. (1990). Current eliminativism. In W. G. Lycan (Ed.),Mind and cognition :A reader
(pp. 206–223). Oxford, England: Basil Blackwell.
Crick, F. H. C. (1994).The astonishing hypothesis :The scientific search for the soul.NewYork:Scribner.
Crick, F. H. C., & Koch, C. (1990). Toward a neurobiological theory of consciousness.Seminars in the
Neurosciences, 2, 263–275.
Crick, F. H. C., & Koch, C. (1995). Are we aware of neural activity in primary visual cortex?Nature,
375 , 121–123.
Crick, F. H. C., & Koch, C. (1998). Consciousness and neuroscience.Cerebral cortex, 8, 97–107.
Cronholm, B. (1951). Phantom limbs in amputees.Acta Psychiatrica Scandinavica, 72(Suppl.).
Dennett, D. (1991).Consciousness Explained. Boston: Little, Brown.
Edelman, G. M. (1989).The remembered present :A biological theory of consciousness.NewYork:Basic
Books.
Kim, J. (1978). Supervenience and nomological incommensurables.American Philosophical Quarterly,
15 , 149–156.
Kim, J. (1993).Supervenience and mind. Cambridge, England: Cambridge University Press.
Locke, J. (1690/1987).An essay concerning human understanding. Oxford, England: Basil Blackwell.
Nagel, T. (1974). What is it like to be a bat?The Philosophical Review, 83 , 435–450.
Palmer,S.E.(1999).Color,consciousness,andtheisomorphismconstraint.Behavioural and Brain
Sciences, 22 (6), 923–989.
Putnam, H. (1960). Minds and machines. In S. Hoo k(Ed.),Dimensions of mind.NewYork:Collier
Books.
20 Stephen E. Palmer