First, I would like to apologize for not getting back to my interlocutors more promptly. I have to do blog postings at times when there are no other pressing duties, and there have been no such times for the past month. My previous post on August 31, “More on Metaphysical Naturalism and Consciousness” prompted much high-quality response, and I find that gratifying. I would like to respond to some of these responses. Unfortunately, it may be another month before I can continue the conversation again.

Dianelos Georgoudis says:

“Keith Parsons says that conscious experiences are activities of physical beings accomplished via the functionality of some bodily part (presumably their brain), and that people digest with some body parts, and experience with some others. The fundamental difference of course is that we observe the stomach digesting, but we don’t observe the brain experiencing. Rather we observe the brain causing behavior.”

In the 1960’s science fiction movie Fantastic Voyage, the micronauts are inside the brain and they see neurons firing. One comments that they have just witnessed a thought. At the time this seemed silly (at the time I was fifteen and was watching the movie largely in hopes that Raquel Welch would disrobe). Now the idea that we can observe a brain thinking or experiencing does not seem silly. In fact, we can witness such occurrences. Brain imaging techniques allow us to witness the brain’s functions better than any micronaut could. When a subject is shown a bright red object, we can watch the visual cortex and observe its activities. When observing brain activities while the subject is having certain experiences, we are observing the brain experiencing. To reply that we are not observing the brain experiencing, but only the physical correlates of experience would be to blatantly beg the question against the physicalist view that experiences are fully realized in physical processes that occur in the brain. On this view, we are observing experiencing in precisely the same sense that we observe the ballerina do a pirouette. A pirouette is something the ballerina does with her muscles and experiencing is something she does with her brain.

Dianelos says:

“Indeed to call consciousness a phenomenon strikes me as a category mistake. Rather, consciousness is what makes it possible for phenomena to exist: In a world without consciousness there would be events but no phenomena.”

A phenomenon is an observable event. If, indeed, we can see someone’s brain in the act of experiencing (through the instrumentality of an imaging device), then such experiencing is an observable event. Even in the first person sense, I am not just aware, but I am aware that I am aware. I do not just perceive; I perceive that I perceive. Thus, perception, for instance, seems to be a straightforwardly perceptible occurrence; I can perceive it in others and I can perceive its occurrence in myself. Therefore, there is no problem at all with talking about the phenomena of consciousness. Further, it is simply false to say that without consciousness there would be events but no phenomena. An event can be observable even if there are no observers to observe it. Likewise, a vase can be breakable even if it is hidden away where no one can break it.

Dianelos says:

“Conscious experiences themselves are clearly not objectively observable as evidenced by the fact that we can’t observe whether thermostats, or for that matter cockroaches or computers, do have them. Similarly we can’t observe a bat’s experience of echolocation.”

Maybe I am misunderstanding, but these statements seem to involve a basic confusion. Thomas Nagel’s point in “What is it like to be a bat?” was that even if we have an exhaustive understanding of how echolocation works, we will still not know what it is like to experience echolocation and therefore will never be able to know what it is like to be a bat. His point was that consciousness has an elusive, ineffable quality—the “what it is like” to have a particular kind of experience—that science cannot capture, and, therefore, that consciousness has properties that necessarily elude scientific accounts. Dianelos seems to be conflating two distinct questions here: (a) Can we observe (e.g., through brain imaging) the bat’s experiencing of echolocation? And (b) Can we experience echolocation in the way that a bat does. The answer to the first is “yes” and the second is “no.”

I am happy to admit that I do not know what it is like to be a bat. I am not sure that I can even really know what it is like to be an Australian aborigine. But if we could observe a bat’s brain as it negotiates obstacles in pitch darkness using echolocation, then, we would be observing its experiencing of echolocation in precisely the same way that we can observe its flapping of its wings. Of course, we do not experience what the bat experiences, since we are not hooked up to its sensory apparatus in the way that it is. However, if the bat’s conscious experiences are fully realized in its brain processes (and surely this is uncontroversially the case with bats, right??) then in observing its brain processes we are ipso facto observing its experience of echolocation. In observing the bat’s experiencing, I do not have to feel what the bat feels any more than I have to do a pirouette to observe the ballerina do one.

Maybe Dianelos’ point is this: We know that the ballerina is doing a pirouette as soon as we see her go up on the tips of her toes. With observing the internal processes of an animal’s brain, however, we have to first establish that the physical process we are seeing is also a conscious process. That is something that has to be inferred, and is not simply observed, like the pirouette. Again, though, the postulation of consciousness can be the best explanation of a set of observations. For pet owners, the inference is well nigh unavoidable. Perhaps the dog who brings his leash does not want to walk, or the cat who brings her toy does not want you to play with her. Maybe also it was a zombie Descartes who uttered “Sum res cogitans.” In principle and in practice, though, inferring the existence of conscious states is often reasonable, and sometimes compelling.

Dianelos says:

“…if explanations in terms of esthetic intuitions can be subsumed under physiological explanation then the former cannot be the *best* explanation. Significantly Keith claims that “ the fact that explanations in terms of A’s subsume explanations in terms of B’s does not mean that B’s do not exist or are not useful, indeed, indispensable, at certain levels of explanation.” I think this is a key point. I agree that the B’s can be useful in some contexts, and even indispensable sometimes as a practical matter. But I strongly disagree that the B’s can be said to exist in objective reality. In the case of gravitational phenomena the currently best explanation assumes the existence of curved spacetime and not of gravitational force fields. Nevertheless people find it useful to continue using Newtonian mechanics and gravitational force fields in many contexts (e.g. while engineering an airplane). But nobody who knows about general relativity believes that gravitational force fields exist in reality.”

There are two points to be made here: First, there is a pragmatic element in what counts as the “best” explanation; it depends in part on the sense of the “why” question we are asking. This was Socrates’ point when he noted that there are two different ways to explain why Socrates is sitting. We can explain it in terms of the pattern of tension and relaxation in Socrates’ muscles, or we can explain it in terms of Socrates’ intentions, e.g., that he is sitting in order to converse with Euthyphro. Which sort of explanation we judge “be

st” will depend upon the sense of our question about why Socrates is sitting. Likewise, if we are asking why an aesthetic judgment is made, we expect an answer in terms of an aesthetic principle, insight, intuition, etc., not in terms of neurophysiology, even if our aesthetic thinking, like all of our thinking, is wholly realized in physiological processes.

The second point is that it simply is not true that, in general, if explanations in terms of A’s subsume explanations in terms of B’s, the B’s no longer exist. If it were true, we would have to say, e.g., that carburetors do not exist (n.b., my knowledge of automobile engines stems from the pre-fuel injection era). We sometimes explain engine function and malfunction in terms of carburetors, though, surely, everything carburetors do can be subsumed under explanations in terms of physics. Maybe Dianelos would bite the bullet and say that, strictly speaking, carburetors do not exist, but I would have to see his argument (and it would have to be a very good argument). In the meantime, there seems to be no reason to deny that artistic creativity exists even if the thoughts of a Beethoven or a Picasso are physically realized as brain functions.

Dianelos says:

“Which brings me back to my pointing out that the fact that the physical universe appears to be causally closed does not imply that it is. If there is a qualitative/personal dimension to reality beyond the quantitative/physical one, then the question arises about the relationship between these two dimensions, a question that has bedeviled dualists for centuries. My argument is that it is entirely possible for the conscious dimension to cause events in the physical plane, while all events on the physical plane are nonetheless causally closed (i.e. can be explained without the need to assume the existence of the conscious dimension).”

Even if there is some conceivable way that the “conscious dimension” could cause events in the “physical plane” without disrupting the causal closure of the physical (and I just do not have time right now to enter into the complexities of this point), surely the following epistemic principle holds:

If it is apparent that p, then we should tentatively conclude that p, unless there are sufficient grounds for thinking that appearances are deceiving here.

If, as Dianelos seems to concede, physical causes apparently are sufficient for all physical effects, then, the thing to do is to conclude, tentatively, that physical causes are sufficient.