This handout doesn't contain detailed notes on the chapters, just some issues I hope we can discuss in class.
1. The zombie argument. (We've discussed this at some length already, so should probably focus on other things in class today.)
1. I can consistently conceive of beings that are physically identical with us, yet have no conscious experiences
2. Conceivability implies possibility
3. Therefore, physicalism is false (since it implies that zombies are impossible)Note that it's logical possibility that is involved here, not natural possibility. Some (e.g. Chalmers) hold that zombies are naturally impossible, that is could not occur given the laws of nature, but logically possible.
The most common place to attack this argument is at premise 2. Dennett, however, attacks premise 1 instead: his view is that the idea of a zombie is literally incoherent. If you try to think through the idea, you'll realize that there's no consistent way to tell the story.
2. Heterophenomenology. What is it? Why is it called that? Can it tell us all there is to know about consciousness? (Note: closely related to the knowledge argument.)
| science can give us a complete account of consciousness | science cannot give us a complete account of consciousness | |
| consciousness is irreducibly subjective | Searle [science can include facts about subjectivity] | Chalmers [science can tell us about the causes and effects of consiousness, but not about its intrinsic properties] |
| consciousness is not irreducibly subjective | Dennett [there are no irreducibly subjective facts] | ??? |
Usual picture: heterophenomenology --> real phenomenology --> underlying neural phenomena
or: reports of qualia --> actual qualia --> underlying neural phenomenaDennett's picture: heterophenomenology --> XXXXX --> underlying neural phenomena
or: reports of qualia --> XXXXXX --> underlying neural phenomenaThat is, the usual picture is that reports of experience/qualia report something real, namely experience/qualia. On Dennett's view, reports of experience are just stories we tell ourselves and others; they may be partly based on something real (namely neural phenomena), and they may be partly fictional, but there's no real phenomenology in between the reports and the neural phenomena.
3. Consciousness as magic. It seems like something really magical (i.e. supernatural), but that's just a trick (or a collection of lots of tricks), and we can explain how the trick works.
Explaining how the trick works is explaining all of the functional and neural mechanisms that underlie our reports of conscious experience. Contrast Chalmers, who maintains that explaining functional and neural facts is the "easy problem," and leaves the "hard problem" untouched.
Dennett: "[T]he tempting idea that there is a Hard Problem is simply a mistake" (p. 72).
4. Change blindness examples. Did your qualia change between pictures before you noticed what the difference was?
Yes: then neuroscience (or some other objective methodology) must be the right way to study qualia
No: then heterophenomenology must be the right way to study qualia, since we're guaranteeing that qualia can't change unless reports change. (If so, then zombies have qualia, since they report having them.)
I don't know: why not? If it's because you don't know what 'qualia' is supposed to refer to, then we need to clarify the question (or perhaps because the notion of qualia just doesn't make any sense). If it's because you think that there's some neural fact that needs to be discovered, we're back to neuroscience being the right way to study qualia.
The only other possibility seems to be that there are facts about qualia which are not accessible at all: not from the first-person point of view, and not from any third-person point of view.
Last update:
November 11, 2009.
Curtis Brown | Philosophy of Mind | Philosophy Department
| Trinity University
cbrown@trinity.edu