Specter of Reason

David Chalmers is famous for, among other things, claiming that zombies are conceivable.  Not movie zombies, but zombies of a different sort.  These zombies are beings which are physically and functionally identical to human beings, but which lack a certain kind of conscious experience.  They lack the "what it is like" that is said to characterize our experiences.  Another way of putting it:  They lack phenomenal consciousness. According to Chalmers, zombies act just like us, and that means they talk about things just the way we do.  They therefore have intentionality.  Their behaviours are about things.  It follows that, if zombies are conceivable (i.e., conceptually coherent) then there are intentional states that lack phenomenal content. This seems like a difficult position to hold.  My intuition is that all intentional states have phenomenal content.  I wonder what arguments have been made one way or the other.  The conceiva...

Several scientists have made a declaration on consciousness .  (You can read coverage from a  Scientific American blog  here .) Unfortunately, I think the declaration is more likely to promote confusion rather than clarity. What does it mean to "experience affective states?" What characterizes intentional behavior as such? These are problematic questions and I don't see this declaration helping matters. They seem to be ignoring the difficulties, not overcoming them. One basic difficulty is that the word "consciousness" has multiple recognized definitions. For most people, I think if you told them octopuses had consciousness, they'd think that octopuses had self-awareness, higher order thoughts about their lives and experiences, and such. But that is not what the science shows. (I'm not saying octopuses don't have these things, but only that the science doesn't show it.) I suspect that the scientists making this declaration take "consciou...

There is no good definition of "consciousness"--at least, not in any rigorous philosophical or scientific sense. There are just lots of ways we use the term in everyday life. For example, we use it to distinguish between sleep and wakefulness, or to indicate that we are focusing our attention on something, or that we remember something, or that we know something. These aren't all the same, or even necessarily similar, processes. So the idea that there is some unique thing called "consciousness" is perhaps an error. And so the idea that there are "conscious processes" in the brain is also perhaps an error. The word "consciousness" does not pick out anything specific, but has meaning only in so far as it provides some structure to our discourse--specifically, our discourse about ourselves. It is a grammatical construction without extra-linguistic referent. * Once we've understood the language, we've understood consciousness. Th...

A few days ago I posted the following in a discussion at PhilPapers : Not far into Consciousness Explained (paperback, p. 23), Dennett writes: "Today we talk about our conscious decisions and unconscious habits, about the conscious experience we enjoy (in contrast to, say, automatic cash machines, which have no such experiences) -- but we are no longer quite sure we know what we mean when we say these things. While there are still thinkers who gamely hold out for consciousness being some one genuine precious thing (like love, like gold), a thing that is just 'obvious' and very, very special, the suspicion is growing that this is an illusion. Perhaps the various phenomena that conspire to create the sense of a single mysterious phenomenon have no more ultimate or essential unity than the various phenomena that contribute to the sense that love is a simple thing." I think understanding this passage is critical to understanding Dennett's approach. Our talk of co...

Nothing is more obvious or immediate to our minds than the fact of our own consciousness. And yet, consciousness seems so bizarre and mysterious, some say it is beyond any hope of an explanation. How can something be so clear and present in our minds, and at the same time be so hard to understand? Philosophers and scientists have argued for ages about how to solve this puzzle, and sometimes about whether or not there really is a puzzle at all. My view is that consciousness is not a philosophical puzzle, but a scientific issue which can only be worked out through a better understanding of physiology. In our case, that means understanding how our bodies and brains function. One of the reasons consciousness is so valuable to us is that it allows us to capitalize on amazingly complex information processes without having to pay attention to many of them. If we had to focus on everything going on in our heads, we'd never get anything done. C onsciousness is not directly concerned wit...