Jun 10 2008

Ether of the Mind: Chalmers and Dennett on Dualism

Consciousness is undoubtedly one of the most complex and interesting phenomena in the universe. Wrapping our minds around the concept of mind has vexed philosophers and scientists for centuries – perhaps because it is the task of the brain trying to understand itself. This has led to many theories and bizarre beliefs about consciousness – that it is non-physical, that it is due to quantum weirdness, or that it requires new laws of nature to explain. And yet modern philosophers and neuroscientists are increasingly of the opinion that perhaps it’s not such a hard problem after all. Perhaps the real trick is realizing that it’s not even a problem at all.

Yesterday I wrote my most recent reply to Michael Egnor’s rather lame attempt at defending what is called cartesian dualism – the notion that consciousness requires the addition of something non-physical. Ironically he invoked the writings of David Chalmers to his cause, not realizing (or not caring) that Chalmers is a harsh critic of cartesian dualism and rather supports what he calls “naturalistic dualism.” Chalmers believes that the “something extra” required to explain consciousness is a new law of nature, not a non-physical spiritus.

Today I will discuss Chalmers’ proposed solution (actually he points the way to a solution but acknowledges he does not yet have one) and its major critic, Daniel Dennett.


The Problem of Subjectivity

At the core of the debate over consciousness is the nature of subjective experience. Why is it that we have subjective experience, that we feel, and we have the sense that we exist? Why aren’t we, as David Chalmers asks, just “zombies” – carrying out all of the processes of life without experiencing it?

Part of the enduring controversy over this question is that it intersects with a deeper question about the nature of science itself. Can science rely upon subjective experience to understand nature? Or (a related question) can science formulate models of reality that include elements that cannot be objectively observed and tested? If we don’t allow subjectivity, then how do we study the phenomenon of subjective experience itself?

I admit this is a thorny problem. Former Buddhist monk, B. Alan Wallace, has written a number of books and articles advocating, for this reason, the reintroduction of subjective experience into scientific thinking. I disagree with him on this point, and also on the way in which he invokes quantum mechanics to support his form of dualism – but this is a topic of a future post (perhaps later this week).

The question of whether or not science should restrict itself to the observable and testable has plagued the world of physics since the time of Einstein and the death of the classical model of nature. In the classical world there was no doubt that what we observe about the world is the same as the way the world actually is. Quantum mechanics put an end to this simplicity.

In the quantum world, elegant experiments have shown us that nature, at its fundamental level, is counterintuitive. Matter exists simultaneously as both a wave and a particle, and the properties of matter can only be described statistically based upon probability – the Heisenberg uncertainty principle, that we can only know so much about the physical properties of matter, laid waste to classical determinism.

This lead to the great question – is quantum mechanics simply a system that accurately describes and predicts what we see during experiments, or does it describe the way nature actually is – and (here’s the really important bit) is there a difference?

Ironically, Albert Einstein revolutionized physics with relativity theory by being the first physicist to say that the variability of time and space is not just a system for explaining observation – it actually describes the way the universe works. Prior to Einstein physicists invoked the ether – an unseen and unknown substance permeating all space and through which light propagated. The ether was a fix to rescue classical physics from the observations of reality. Einstein then, later in life, took the opposite position by resisting the notion that quantum mechanics actually described nature, as opposed to just our experiments. (This is summarized by his famous quip, “God does not play dice with the universe.”) Einstein wanted (but failed) to develop a unified field theory to explain what was really going on (to rescue the classic world he helped destroy), while younger physicists, such as Max Born, argued that what we see is what we get – science must restrict itself to what can be tested and observed.

So What is Consciousness

This same type of dilemma that so vexed Einstein is now faced by philosophers and scientists trying to crack the consciousness nut. Everyone (outside of cartesian dualists) seems to agree that neuroscience is making tremendous progress in explaining what Chalmers calls “the easy problems” of neuroscience – explaining observable, objective, measurable mental phenomena as brain states and function. But neuroscience has not offered an explanation for the subjective experience of consciousness – the “hard problem.” (Chalmers outlines his views in this paper published in 1995.)

Chalmers believes that there is something more that is needed than a reductionist description of brain function. He thinks there is a higher order natural process going on – an actual new law of nature as fundamental as electromagnetism – that explains how brain activity causes consciousness.

I think this is akin to Einstein’s desire to find an underlying unifying theory of physics that would do away with all the apparent quantum weirdness. Chalmers wants to find a “grand unification theory” of consciousness. His imagined new law of nature is his ether of the mind.

Chalmers may ultimately be correct (just as Einstein may ultimately turn out to have been correct – we may yet find some deeper reality underlying quantum mechanics). I cannot think of any reason why Chalmers must be wrong – there may be some higher order process going on. But at this point I find Chalmers’ proposition as unnecessary as the ether.

Further, Chalmers also says that perhaps consciousness arises from some property of nature that science cannot discover, even in principle. This gets back to the argument about the nature of science – do the methods of science tell us how nature is, or just that part of nature that science can test? I believe it must be the latter – untestable notions have no useful place in science. Chalmers’ untestable law of consciousness cannot lead anywhere.

Emergent Phenomenon

Perhaps the most direct challenge to Chalmers has come from philosophy Daniel Dennett. He has raised a number of excellent points challenging Chalmers’ contention of the hard problem. Particularly revealing is the analogy to vitalism – the notion of a vital life force that separates animate from inanimate objects. He writes:

The easy problems of life include those of explaining the following phenomena: reproduction, development, growth, metabolism, self-repair, immunological self-defense, . . . . These are not all that easy, of course, and it may take another century or so to work out the fine points, but they are easy compared to the really hard problem: life itself. We can imagine something that was capable of reproduction, development, growth, metabolism, self-repair and immunological self-defense, but that wasn’t, you know, alive. The residual mystery of life would be untouched by solutions to all the easy problems. In fact, when I read your accounts of life, I am left feeling like the victim of a bait-and-switch.

This imaginary vitalist just doesn’t see how the solution to all the easy problems amounts to a solution to the imagined hard problem. Somehow this vitalist has got under the impression that being alive is something over and above all these subsidiary component phenomena. I don’t know what we can do about such a person beyond just patiently saying: your exercise in imagination has misfired; you can’t imagine what you say you can, and just saying you can doesn’t cut any ice. (Dennett, 1991, p.281-2)

Therefore the vitalists of old claimed that a vital force was necessary to explain life. Biologists then proceeded to explain all the components of life until nothing was left for vitalism to explain, except a vague sense that being alive is somehow a thing unto itself. Dennett compares this to the dualists (all dualists, including naturalistic dualists like Chalmers) – if neuroscience can explain all of the cognitive phenomena that we can observe: memory, perceptive, communication, reflection, etc., then perhaps it has explained consciousness as well as biology has explained life. Then there would be no more need for a separate explanation for consciousness as there is for a vitalistic force to explain life.

In other words – life is what we collectively call a host of complex and organized chemical reactions resulting in the ability to use energy for growth and reproduction. Life emerges from the component parts that make it up, but there is no extra thing that is life.

Likewise, perhaps consciousness is what emerges when the brain is actively engaged in its various functions. When we are perceiving stimuli, keeping information in our working memory and manipulating it, carrying on an internal conversation with ourselves, etc. – all of these things add up to consciousness without the need for any extra added thing. In this sense consciousness in an emergent phenomenon – not a new law of nature or a bit of mysterious magic. While I admit it is difficult to fully comprehend this notion, I find it the most compelling of all the options.

Chalmers’ primary objection comes down to – why do we experience anything? Why aren’t we zombies – carrying out all the functions we ascribe to consciousness without being conscious. I think the simple answer is – what’s the difference? What if carrying out all the functions of consciousness IS consciousness?

Dennett explains it thusly:

What impresses me about my own consciousness, as I know it so intimately, is my delight in some features and dismay over others, my distraction and concentration, my unnamable sinking feelings of foreboding and my blithe disregard of some perceptual details, my obsessions and oversights, my ability to conjure up fantasies, my inability to hold more than a few items in consciousness at a time, my ability to be moved to tears by a vivid recollection of the death of a loved one, my inability to catch myself in the act of framing the words I sometimes say to myself, and so forth. These are all “merely” the “performance of functions” or the manifestation of various complex dispositions to perform functions. In the course of making an introspective catalogue of evidence, I wouldn’t know what I was thinking about if I couldn’t identify them for myself by these functional differentia. Subtract them away, and nothing is left beyond a weird conviction (in some people) that there is some ineffable residue of “qualitative content” bereft of all powers to move us, delight us, annoy us, remind us of anything.

I also add to this that there are different states of consciousness that correlate with different brain states – not just the function changes, but subjective consciousness changes as well. For example – dreaming is a form of consciousness. You are still yourself and you are aware and many of the components of consciousness are there, but it is also different. One difference is that reality testing (a specific cognitive function) is not as active. That is why often dreams make sense to you while you are dreaming but then to your awake consciousness it seems unreal. Being inebriated is also an altered state of consciousness, as are all so-called encephalopathies where overall brain function is impaired.

In other words, if you change or impair the “easy problem” functional components of consciousness you also change consciousness – the simplest explanation for this is that consciousness emerges from those functional components.

Conclusion

Philosophers and scientists still struggle to put into words exactly what consciousness is, and it does defy easy conceptualization. But I think the best explanation, and one that is consistent will all observable phenomena – both what we can objectively measure, and what we subjectively experience – is that consciousness is an emergent property of all that the brain does. I do not think we need to invoke quantum weirdness, I do not think we need to appeal to unfalsifiable inherent laws of nature, nor non-physical causes.

At least that’s what I think.

Share

36 responses so far

36 Responses to “Ether of the Mind: Chalmers and Dennett on Dualism”

  1. Steve Pageon 10 Jun 2008 at 8:46 am

    I’m rapidly coming to the same conclusion, Dr N. The whole is the sum of the parts, and the sum of the parts is so amazing that the whole appears to be more than the sum of the parts possibly could be.

  2. PaulReinon 10 Jun 2008 at 9:01 am

    A very well written summary of the standpoints of Dennett and Chalmers. They are both thought-provoking and thorough in their research and while I tend to agree more with Dennett it is always illuminating to read Chalmers as well.

  3. daveoron 10 Jun 2008 at 9:39 am

    A very interesting blog post. May I suggest Susan Greenfield’s book; The Private Life of the Brain for a very interesting and complete treatment of this topic.

    Here’s the link on amazon:

    http://www.amazon.com/Private-Life-Brain-Emotions-Consciousness/dp/0471399752/ref=pd_bbs_sr_1?ie=UTF8&s=books&qid=1213104555&sr=8-1

  4. tritoneson 10 Jun 2008 at 10:05 am

    To pose two critiques against Dennett, however:

    1) First, one thing Chalmers is getting at, is that a “singularity” emerges once all of the “simple” processes sum. I don’t think Chalmers would deny the idea that consciousness is the experience of all of these processes, but the point is that these processes reach a level of complexity that requires a new language to explain what’s going on as this singularity moves about, than the language which is only focused on underlying processes.

    Yes, adjusting underlying physiological processes impacts consciousness, but not in any simple one-to-one ratio: there is no clearer example than seratonin, which seems to impact mood, but which is not “the happiness” chemical in our brain like reductive SSRI advertisements make it seem. In fact, we can find no direct relationship between seratonin and happiness (especially in the long run), though no one would deny that seratonin is a part of mood (and many other brain processes as well). Understanding seratonin, in fact, continues to tell us less about a person’s mood, than understanding attachment patterns, and affect flow amongst a person and primary care-givers (affect here understood in more behavioral terms, than physiological ones). This is because, one might argue, that once we have a human organism we need to pay attetion to gross organismic processes which cannot simply be understood to be sums of biological ones.

    This leads to the second critique of Dennett/defense of Chalmers: that we know for a fact that ecological factors outside of the nervous system have a much larger impact on consciousness than what is going on in the brain. The classic example here is “hysteria” (today called somatoform borderline personality disorder.) Just one simple example: a person with borderline may have two basic states, one where she is cutting herself, projecting hostile motives on others, and screaming alot, or one where she is calm but she is manipulating others around her into violence, hostility, and suspicion. This “externalizing” acts as some kind of balance of her “internal” state. Getting other people to hold her “disorganization” is calming. Here we see consciousness distributed across individuals, in a way that cannot be reduced, from what I can tell, to the “simple” problems of how a brain works. No medication for anxiety or mood impacts a change at this level for the borderline, which is why it is an Axis II disorder – personality disorder. It is rooted at a more complicated level, not a more base level – it is a problem of the total organism, not the isolated brain.

    Just a few comments. I enjoy the blog tremendously!

    best,
    5HT

  5. Steven Novellaon 10 Jun 2008 at 11:41 am

    tritones – while I agree with your examples, I do not agree that they are a defense of Chalmers against Dennett. What you are basically saying is that there are interactions and complexities that can only be understood at certain higher levels of organization, and cannot be fully explained by looking solely at reductive levels. I agree – but this does not therefore require the addition of a new law of nature at these higher levels – there is not a higher level causal process going on. Rather, there is higher level interactions -patterns that exist only at the higher levels. But these patterns emerge from the reductive processes, they don’t have a separate cause.

  6. Blake Staceyon 10 Jun 2008 at 12:35 pm

    Consider photosynthesis. The ability of a chlorophyll molecule to trap light and capture its energy is not a property of any individual atom within the molecule. The behavior of chlorophyll is constrained by the basic laws of physics, but thanks to the large degree of historical contingency, it is not directly predictable from those basic physical laws. Furthermore, the molecule has sufficiently many parts that even given its structure, calculating its properties knowing only those basic principles is not easy, and we resort to approximations of various kinds.

    There’s no “singularity” here, just the normal process of one science, molecular biology, being founded on another, molecular physics. Introducing new equations, based on approximations and empirical findings, to predict the behavior of aggregated entities is nothing special. Indeed, this is the basic thrust of statistical mechanics, wherein the properties of heat flow and such are deduced from the behaviors of individual atoms.

  7. Roy Nileson 10 Jun 2008 at 3:24 pm

    Consciousness may at bottom be the phenomena perceived by an organism when its sensory input interfaces with its calculative apparatus. The more complicated these mechanistic processes become, the more detailed and intricate the perceptions – and the more varied the areas from which these perceptions seem to arise.

    Humans have obfuscated the process of understanding the nature of consciousness by turning to supernatural sources for its explanation. And have complicated the matter further by assuming it’s a property that humans have almost the exclusive use of – albeit we have grudgingly allowed other so called sapient beings to join this select group.

    But chances are that all life involves having a form of consciousness, although Chalmers may be offering a definition of life that again obscures a proper understanding of the phenomenon.

    If one defines life as a self-sustaining chemical reaction (or energy system) with expectations, it’s not that hard to imagine that consciousness would not require a supernatural force to have introduced it as a part of life at some appropriate stage of its development.

  8. Skeptical Caton 10 Jun 2008 at 3:53 pm

    Intellectually, I agree completely with your post and Dennett’s position.

    However, I still can’t shake some of the mysteriousness surrounding the existence of first person experience. To me, this is most clearly manifested in a series of thought experiments I was discussing with my wife. And pardon me if my problems seem naive; despite having a growing amateur interest, I make no claims to having any skill as a philosopher. ^_^;

    Imagine that someone removes one neuron from your brain. You’d lose an atomic unit of cognitive capacity; not that you’d be able to notice such a thing, but in principle brain function and conscious experience would be reduced (assuming that the neuron was from a part of your brain that makes up conscious experience).

    Now imagine that you are able make a perfect record of that neuron before it is removed, and are then also able to synthesize a perfect functional replica. If the neuron is restored and replaced in your brain exactly as the old one was, then brain function and your conscious experience would also be exactly as it was before. Given the (admittedly unrealistic) assumptions, this doesn’t seem problematic at all.

    Now imagine the same scenario, but remove and replace 2 neurons. Again, assuming everything is arranged the way it was before, you and your subjective experience would continue on unchanged. I can’t imagine any particular n+1 scenario which would change the validity of that, either. So, by induction, you could therefore do this with an entire brain.

    So in effect, you could map out a person’s brain, vaporize it, build a functionally identical copy, and then that person’s consciousness and subjective experience would be unaffected. If you underwent such a procedure, you would still be you, and your experience of the world exactly as it was before. From your perspective, it wouldn’t be any different from any other deep unconsciousness, like from general anesthesia.

    I would have disagreed with this conclusion before I thought about it for awhile, but after going through the thought experiment, I can’t think of any reason why continuity of the physical substrate of the brain would matter in any necessary way for consciousness in the long term. If consciousness is just an emergent property of brain function, then the only thing that matters is that function. Once they wake up, there shouldn’t be any difference between someone who has their brain vaporized and reconstituted, and a person undergoing heart surgery who has hypothermia induced to the point where they have no measurable electrical brain activity.

    I can certainly imagine what this would feel like. As someone prone to vasovagal syncope, I have experience losing consciousness in an abrupt and unnatural manner, only to have it restored without any lasting sense of discontinuity, despite the initial disorientation. ^_^;

    The map-vaporize-reconstitute scenario doesn’t seem problematic to me, and if true would certainly seem to confirm Dennett’s position. However, the problem that I just can’t seem to get my head around is: What would happen if you made a perfect map of a person’s brain, vaporized the original but then instead of just rebuilding it, you made two copies? What happens to the subjective experience of consciousness in that case? What would I experience if this happened to me? I highly doubt there would be a shared subjective experience across both new persons (why would there be?), but there should still be a feeling of more or less continuous experience for both of persons, since I can’t think of anything qualitatively different over having just created a single copy. However, I just can’t figure out what it would mean experientially.

  9. Potter1000on 10 Jun 2008 at 4:15 pm

    My computer just told me that it’s conscious. I’m not sure if I should believe it.

    Now it just said, “No seriously. I swear.”

    I’m so confused.

  10. Roy Nileson 10 Jun 2008 at 4:36 pm

    Potter1000,
    If your computer expects you to believe what it’s saying, it’s not only conscious, it’s alive.

  11. William Lemonon 10 Jun 2008 at 5:26 pm

    This is an interesting series of posts that I subjectively believe that I have been experiencing, although you cannot determine if I have been experiencing them or I simply act like I have been experiencing them. If consciousness is completely subjective, is it observable?

  12. DevilsAdvocateon 10 Jun 2008 at 5:27 pm

    Skeptical Cat, I’m afraid a cartesian and maybe other dualists might decide you had unknowingly mapped and replicated the ghost in the machine as well.

    Very interesting thought experiment, though. You described it so well I got the creepy feeling you intend on trying it soon.

    I’m being silly, right…. right?

  13. Blake Staceyon 10 Jun 2008 at 5:34 pm

    Skeptical Cat,

    The matter in your brain is being replaced all the time. To quote Richard Feynman,

    So what is this mind of ours: what are these atoms with consciousness? Last week’s potatoes! They now can remember what was going on in my mind a year ago — a mind which has long ago been replaced.

    To note that the thing I call my individuality is only a pattern or dance, that is what it means when one discovers how long it takes for the atoms of the brain to be replaced by other atoms. The atoms come into my brain, dance a dance, and then go out — there are always new atoms, but always doing the same dance, remembering what the dance was yesterday.

    I expect that in your thought experiment, both copies would feel an uninterrupted “flow” of consciousness. “OK, I’m lying down here on this bed in the middle of the room with wires hooked up to my head and nanites being injected into my bloodstream. . . hey, suddenly I’m floating in a tub of goo on the left side of the room.”

    Meanwhile, the other copy is thinking, “Hey, suddenly I’m floating in a tub of goo on the right side of the room.”

  14. JimVon 10 Jun 2008 at 6:16 pm

    I had an adverse reaction to the mention of Chalmer’s “zombie” thought-experiment in the previous post. Can some philosopher actually be drawing conclusions based on characteristics of fictional entities from horror films, which make no sense and do not exist in any known species? What’s next, thought experiments involving vampires? (Yes, I know about Maxwell’s Demon – not the same kind of thing in my opinion.)

    I decided there had to be some better argument involved, but I still am not seeing it from the additional information in this post. I think Dennet has it nailed. The universe may be a stranger place than we can imagine, but much that we do imagine has no place in the universe.

  15. Roy Nileson 10 Jun 2008 at 6:37 pm

    One aspect of consciousness is that it provides sensory feedback without which the whole calculative process of life would not work.
    A “zombie” apparatus would have no such feedback and thus would be unable to adapt to a changing environment and would in effect self-destruct.

  16. ellazimmon 10 Jun 2008 at 6:38 pm

    Zombies, like the proverbial lemmings, not having greater awareness/processing/consciousness, are prone to getting destroyed. As natural selection would clearly favour critters with the capacity to remember, analyse and anticipate what is so hard about making the assumption that the mind is what the advanced brain does? Such an advanced machine would need some kind of operating system and when the machine can reprogram itself then that system must be able to make value judgements about what it guesses is the most conducive to survival. It has to be able to “see” itself to impose that judgement if the chosen action requires delayed gratification.

    Plus our patron saint, Ockham, would argue against complicating our explanations.

  17. ellazimmon 10 Jun 2008 at 6:39 pm

    Looks like Roy and I were thinking almost exactly the same thing at the same time. Oooo, must be ESP eh?

  18. Roy Nileson 10 Jun 2008 at 7:57 pm

    Extremely sensitive perspicacity – no doubt about it!

  19. nbarrowmanon 10 Jun 2008 at 11:11 pm

    I have to say that I find the “emergent property” argument completely unsatisfying. It reminds me of the famous Sidney Harris cartoon where the professors are looking at a chalkboard with a series of equations. In the middle are the words “THEN A MIRACLE OCCURS”. One professor remarks to the other “I think you should be more explicit here in step 2.”

  20. vlewskion 10 Jun 2008 at 11:50 pm

    At this point it seems as if the debate hinges on the intuition of the objectivity of subjectivity…while Dennett and Novella emphasize that our knowledge be driven by what can be observed and filtered through the scientific method, others such as ‘property dualist’s’ or
    ‘naturalistic dualist’s’ are proposing that something extra is needed to account for consciousness mostly by proposing psycho-physical hypotheses which line up with the data already present.

    This is where the different interpretations of quantum mechanics get into trouble, they offer nothing new in the way of experimental data to differentiate their theory from the already existing experimental data established under quantum field theory (e.g. Bohmian Mechanics, Information theory, many minds/worlds theory…etc).

    That is why neuroscience is our only and best bet right now, all the experimental data points to consciousness arising from the brain…I presume that the form of reductionism that Dr. Novella endorses encapsulates the functional aspect of consciousness while not relying heavily on the brain as the only structure able to realize the appropriate functionality (e.g. cephelopods).

  21. MKandeferon 11 Jun 2008 at 12:16 am

    nbarrowman,

    Would you find the explanation, “when sharing a covalent bond, two hydrogen atoms and an oxygen atom result in the emergence of water”, unsatisfying? The claim made by emergentists is not that consciousness “miraculously” appears when the brain functions exist, but that consciousness exists when these brain functions AND their interactions do.

    This is somewhat of a sticking point for me. I don’t consider myself an emergentist, but I agree with this position. One of the claims of emergentism is the whole is greater than the sum of its parts. I don’t agree with this claim, but this is probably because I consider such interactions between parts as parts of the system. The standard example of emergentism is an ant colony. In the example, individual ants, the parts, interact as a system, the ant colony. However, the chemical trails and various communication mechanisms the ants utilize are part of the colony, as without them the colony would not exist, so it’s not exactly clear why an ant colony is considered an “emergent” property of ant populations.

    JimV,

    I had a similar reaction when I read a paper in my mereology class that utilized a thought experiment involving ghosts. Apparently, philosophy has no qualms about using fictional entities when drawing conclusions, so long as the arguments are valid. However, philosophical zombies are not the same as Hollywood zombies. They are much trickier beasts that are behaviorally similar to you and I, yet, they do not have qualia. There is no known (thought experiment) test that would distinguish you from your zombie twin.

  22. Roy Nileson 11 Jun 2008 at 1:25 am

    viewski, why draw the line at cephalopod nervous systems? Even bacteria may depend on a form of consciousness for survival.

    Check this from a Scientific American article about quorum sensing: “As its moniker suggests, quorum sensing describes the ways in which bacteria determine how many of them there are in the vicinity. If enough are present (a quorum), they can get down to business or up to mischief. For instance, millions of bioluminescent bacteria might decide to emit light simultaneously so that their host, a squid, can glow–perhaps to distract predators and escape. Or salmonella bacteria might wait until their hordes have amassed before releasing a toxin to sicken their host; if the bacteria had acted as independent assassins rather than as an army, the immune system most likely would have wiped them out.”

    These organisms are exhibiting abilities to communicate, sense changes in surroundings, calculate strategies and levels of risk, utilize feedback in so doing, and even decide from these forms of a sensory and calculative apparatus when there is sufficient strength in numbers to change to attack mode and overcome resistance in their prey.

    If consciousness is emergent, I’d argue that its starting point was not when life forms reached the intelligence level of the cephalopod, but at the point where even the simplest forms used probes, memory, rudimentary calculations, rudimentary forms of communication, feedback, rudimentary strategies and the like.

  23. daedalus2uon 11 Jun 2008 at 7:45 am

    Not all the atoms in the brain do get changed. The DNA isn’t replaced. There is quite good data showing that the C-14 level of the DNA in parts of the brain reflects the C-14 content of the diet when the cells in that part of the brain divided. That would be during very early childhood and not since.

    Memory is not stored in DNA, more likely memory is stored in structures that need to be “refreshed”. Like some types of dynamic ram. If a memory isn’t accessed for many years, maybe it isn’t worth enough to bother keeping.

    During that “refresh”, it is not unlikely that there is some “error correction” and no doubt some “compression” that is changing the memory to make it more “useful” (i.e. corresponding to what is thought to be needed) and to make the retrieval faster, more efficient, to cross reference it to other things and to use up fewer resources.

    Evolution didn’t provide a driving force to make the memory of high fidelity; evolution provided a driving force to make the “memory” an agent for organism survival and reproduction. If the most important cognitive heuristic in your life is skepticism and trying to understand reality as it is, perhaps high fidelity is retained. If the most important cognitive heuristic in your life is that Jesus loves you, perhaps all memories get “refreshed” through that filter (and then become useless for anything else). Reinforcing things like faith and belief and erase things like doubt. Doubt is one thing that greatly slows response time. Erase doubt and response times are faster.

    I think that what many proponents of consciousness are missing is some evidence that there actually is continuity of consciousness. When people experience brain damage do they notice that their consciousness has changed? It is clear from external observers that brain damaged individuals have functional changes in parts of the mind normally considered to be part of consciousness.

  24. nbarrowmanon 11 Jun 2008 at 8:48 am

    MKandeferon,

    Thanks for your thoughtful response to my comment.

    Regarding H2O, I’m not sure I follow you: in this case I wouldn’t call it emergence. More like a definition. I have heard the argument that “wet” is an emergent property. A single water molecule can’t be called wet but if you keep adding water molecules, at a certain point there’s enough water that it can be called wet.

    It still seems to me that the emergentists are saying that at a certain level of complexity (presumably relating to interactions) something mysterious happens and consciousness blossoms. I just don’t see how that could be, and I have yet to hear anyone propose a plausible mechanism.

  25. JimVon 11 Jun 2008 at 12:04 pm

    MKandeferon 11 Jun 2008 at 12:16 am :

    That helped a little, but not a lot. If philosophers can’t base their arguments on actual, observable entities, such as dogs, ant colonies, and so on, I am suspicious that they haven’t garnered enough knowledge to justify conclusions . (Anyone can spin a theory given just a few facts; I do it all the time; the tough part is satisfying all the facts). The commenters just after me (perhaps coincidentally) amplified the issues I have with the notion of zombies.

    Perhaps those issues are dealt with in the definition of “philosophical zombies”, but again, when someone answers every objection by redefining a concept until there is no way to distinquish it from what it is supposed to be contrasting, I lose interest in the argument.

    Anyway, thanks for your response. (And apologies to Dr. Dennett for misspelling his name the first time.)

  26. orestesmantraon 12 Jun 2008 at 9:16 am

    The problem with reducing the mind to an “emergent property” of the brain, is that such an approach stinks of Cartesian psychology. That is to say, reducing the mind to just the nervous system deemphasizes the role the body and social/physical environment play in terms of structuring consciousness. By limiting the entire mind to strictly the nervous system you are incapable of dealing with the holistic nature of the brain/body/world system which can only be captured using a scientific approach which looks at how the body is coupled to the environment.

    Furthermore, I think a philosophical case can be made which, on the ontological level, extends the mind into the environment and not just inside of our skulls. The existential significance of our embodied, engaged perception indicates that cognition goes beyond the boundaries of our skin, and bleeds into the environment, especially with items that depend on human contexts, such as equipment. You can’t understand the role equipment plays in human experience without also understanding their holistic nature. That is to say, you can’t understand a hammer just by reducing it to the physical level – that of a wood shank and a metal blob – you need to understand the holistic referential contexts involved: you can’t understand a hammer without understanding nails, buildings, wood, etc.

    But perhaps the best reason that it is futile and philosophically misleading to reduce the mind to just the nervous system is that you can’t capture Being-in-the-world with a series of formal rules and theorems. For instance, how do you capture in explicit rules the tacit how-to knowledge of everyday practical existence? How can you formalize your implicit knowledge of how to act in social situations? What is the proper distance to stand away from someone in a conversation? There isn’t any rule for this, there is only tacit know-how, not know-that. This level of experience is pre-theoretical and can only be captured through phenomenological interpretation. Thus, to reduce the mind to the brain stinks of Cartesian psychology, which de-situates and disembodies the mind into an ontological category locked inside our skulls. This approach misses the existential phenomena of everyday practical living.

  27. orestesmantraon 12 Jun 2008 at 9:17 am

    Might I also add that just because the mind supervenes upon the brain, doesn’t mean that the mind can be reduced to the brain.

  28. Steven Novellaon 12 Jun 2008 at 10:42 am

    orestesmantra,

    I disagree. You are making a tangential argument and therefore it is a non sequitur. The question is – what CAUSES the mind. Philosophy and science, in my opinion, leads to one answer – the functioning of the brain. This is not hyper-reductionist. This is appropriately reductionist.

    You are talking about uses to which the mind is put. Your hammer analogy is actually apt – but you miss the true implication. If the question is – how does a hammer work – how does it push nails into wood. You can reduce that question to physics. That absolutely does not mean that you are therefore trying to reduce all cultural history of hammers, the uses to which hammer are put, all the complexities of construction, etc. to the same physics.

    Saying that the mind is entirely caused by the brain and is an emergent property of brain function is not a statement about psychology. Psychology, culture, etc., while rooted int he mind, operate at their own level and cannot be reduced to brain function. That would be hyperreductionist.

  29. mrgnashon 13 Jun 2008 at 8:37 pm

    I have to wholeheartedly agree with Dr. Novella and Dr. Dennett here. Even as a neophyte student of psychology, without any specialized training in neuroscience, it’s abundantly clear to me that ‘consciousness’ or ‘the mind’ is merely the ‘operating system’ (to borrow a computing metaphor), that your brain runs in order to interface with reality in a manner advantageous to survival. Having somewhat of a psychodynamic bent, I do think that the study of subjective states does have a place — at least within my own field of clinical psychology — but doing so does not require the premise of some ethereal substance, whether it be mystical or ‘naturalistic.’

  30. joseon 15 Jun 2008 at 9:45 am

    Nice post, wrong conclusions.

    @ Steve

    Nice illustrative post, but I think you are misleading your readers in some respects:

    >modern philosophers and neuroscientists are increasingly of the opinion that perhaps it’s not such a hard problem after all.

    Actually, modern *philosophers* are increasingly of the opinion that it may be a harder problem to crack than previously thought. The heyday of materialism was in the 50′s and 60′s. Since then (1970′s onwards) there has been a series of hard critisims to it, to the point where nowadays (neo-)dualism/monism is viable and respectable.

    Denett’s ideas, while very popular within the scientific community and among popular science fans, are a minority in academia, same with other popular (in the sense just explained) materialist philosophers such as Patricia and Paul Churchland that broadly fit the label ‘eliminativist’. In fact they are seen as marginal even by the majority of other materialist philosophers because they seem to ignore the obvious: that there is a phenomenon to explain that you cant just eliminate (hence ‘eliminativist’) by just stating theres nothing to explain. You yourself seem to be inclined that way: “perhaps the real trick is realizing that it’s not even a problem at all”. Most philosophers, again even materialist ones, view eliminativism as either dishonest or confused (or both!) as they suspect its the result of a misdirected atheist agenda or perhaps of not understanding the issue at hand.

    >untestable notions have no useful place in science. Chalmers’ untestable law of consciousness cannot lead anywhere.

    I agree with you that untestable notions have no useful place *in science*. But I dont think you can infer from that that untestable laws cannot lead anywhere. If youre an honest truth-seeker, you should see the value of knowing that there are real phenomena /aspects of reality that your method of inquiry, science in this case, cannot tackle. But philosophy can and should (and does).

    >why do we experience anything? Why aren’t we zombies – carrying out all the >functions we ascribe to consciousness without being conscious. I think the simple answer is – what’s the difference? What if carrying out all the functions of consciousness IS consciousness?

    This argument/reply was put forward by materialists several decades ago but got into trouble when people came up with the following counter-argument (called the inverted-qualia-argument and closely linked to the zombies-argument):

    Imagine that your twin brother ( if you had one) experiences the colour red with the same quality as you experience the colour green and viceversa, all things being equal. At a certain level of abstraction, you both carry out identical brain functions and yet your conscious experience will be different.

    *That* is the difference and thats why your answer doesnt work.

    The problem for science as a way to explain consciousness is that it seems that no matter how well you describe brain functions you still cant get at the issue of the subjective quality of those functions. Not just why those qualities are the way they are, but why they exist at all.

  31. wonderon 16 Jun 2008 at 10:03 am

    Dennett makes a pretty good case in his book that the conscious experiences of the brothers in your thought experiment wouldn’t be different. If I recall correctly he gave the example of an experiment where people wore for a few days some kind of visor that changed the colours of everything. After a few days people in the experiment reported that the colours had returned to what they usually were (grass being green and so on), and it was taking off the visor that caused all the colours to become wacky again.

    And also I thought I’d provide a little input on the reductionist thing. I think that psychology, culture, etc can be reduced to brain function, but speaking of such things in the language of brain function would be entirely incomprehensible. To indulge in an analogy, a programming language such as C++ or whatever is in principle reducible to machine code (1s and 0s), but nobody would dare to attempt to write a program in machine code in the same way that nobody would talk about culture in the language of brain function – it’s just impossible. My understanding is that the materialist position is just that such a reduction is possible *in principle*, not that we can meaningfully talk about the mind in terms of the brain, which seems fairly innocent to me.

  32. Roy Nileson 16 Jun 2008 at 10:49 pm

    How silly can some of you people get? Removing the supernatural as a necessary part of the equation by demonstrating such an aspect is not only unnecessary but deliberately obfuscative is not reductionism. Unless getting healthy by losing gobs of harmful fat is reductionism.

    And if any misdirected agenda were involved, it would have to be one that introduced the supernatural element to begin with, so that humans could be distinguished “in principle” – if not in kind – from “lower” animal forms.

    And it turns out that there are differences in identical twins that revolve around the mitochondrial DNA. But even if there weren’t, the
    inverted-qualia-argument boils down to a meaningless tautology.

  33. hartfordaromason 17 Jun 2008 at 3:55 am

    Someone wrote consciousness is an awareness which is aware of itself, and another wrote consciousness is awareness of a prescence, always there watching.

    My own sense is we experience brain function, and a little something else. The notion that consciousness is just a biological by-product conjures up philosophies espousing existence is only in your mind.

    As for the ‘untestable’ I suggest the continued evolution of science will bring new ways to know what is not knowable now. As it always has.

  34. Fifion 17 Jun 2008 at 11:31 am

    “The problem for science as a way to explain consciousness is that it seems that no matter how well you describe brain functions you still cant get at the issue of the subjective quality of those functions. Not just why those qualities are the way they are, but why they exist at all.”

    Sure you can. And it doesn’t make philosophy useless either (only those lines of philosophical investigation which greater understanding of neurobiology – and the associated subjective experiences – reveal to be going in a highly unlikely direction). Philosophy and cultural studies of various kinds – and some particular schools of each – seem to be having some difficulty integrating new understandings regarding neurobiology that negate particular dogmas (within feminism the understanding of gender and biology has negated certain theories based on the idea that nurture trumps nature, for instance, and obviously a lot of philosophy has roots in religion and the idea that man is above and separate from nature). Particularly in disciplines that are largely academic, there’s some real resistance to accepting scientific understandings that overturn conventional understandings (particularly ones that are enshrined in other aspects of culture and are so taken for granted that insiders never really see them).

    Let’s look at this point by point. What do you mean when you say that it’s a “problem for science” to describe a brain function to “get at the issue of the subjective quality of those functions”? And what do you even mean by this?

    Understanding (and therefor having the ability to describe) a particular brain function can indeed reveal all kinds of things about the subjective qualities of those functions (what we experience when the brain functions in a certain way) when looked at in a variety of people. Certain kinds of brain damage create quite predictable effects (which are experienced in quite predictable ways). We know that when the brain functions in a certain manner then there’ll be a certain quality to what someone experiences (taking into consideration our own subjective filters that shape how we describe our experiences to ourselves).

    A bit of basic understanding of evolution and biology helps us understand why our neurobiology evolved a certain way. Certainly there’s still plenty of exploring, experimenting and understanding to still do but your objections don’t really hold much water from what I can see.

    As for sharing emotions and comparing our subjective experiences and perspectives, that’s one of the reasons we developed various forms of art. Science doesn’t serve the same purposes as art (though the two meet on common ground all the time). Interestingly, science and art get along very well and are very complimentary disciples. I suspect this is because art recognizes and celebrates subjectivity for what it is, subjectivity (and artists also tend to be quite aware of the tricks our senses can play on us and to use this understanding to create their work). Science and religion (and philosophy, and even psychology at times depending on the school of psychology) can sometimes have a more conflicted relationship because religion/philosophy/psychology sometimes directly compete with science to describe the world.

  35. joseon 17 Jun 2008 at 5:25 pm

    @ Wonder

    OK, we are talking different things here. The inverted-qualia argument is about the idea that function cannot fully explain consciousness, because consciousness is the intrinsic or subjective quality of experience. It has got not so much with _how_ the brain works but with why some of the activities of the brain have an experiential quality at all instead of being non-experienced. For instance, the pupillary response is an unconscious reflex whereas sneezing is a conscious one. The kind of question that zombies/inverted-quality* arguments touch upon is why sneezing is felt at all instead of being un-felt (and the same with all the conscious experiences we have) and not why the wiring in the brain in each case makes the difference between conscious and unconscious.

    The standard response from materialists is double. On the one hand they try to explain why something is conscious using differential brain function, which as explained above misses the point. On the other hand they state that the function _is_ the experience. Now, because its not obvious that that’s the case, they have to do a lot of hard work trying to prove their point. And thats where current philosopy of mind debates are stuck.

    On the subject of reductionism, I am, unlike you, convinced that you can reduce mind to brain as long as you stick to function, ie, the ‘easy’ problems. At the end of the day you _can_ reduce C++ to binary, even if no one in their right mind would want to do that for any serious purpose.

    * The classic version of the inverted-qualia argument asks you to imagine an alternate world or a parallel world where the same functions are experienced differently.

    @ Roy Niles

    Im all for an atheist agenda for not a veiled one and certainly not for one in the wrong place. If Dennet wants to argue for atheism he should do so explicitly in the right forums instead of denying universal intuitions afraid that they could lead to some sort of belief in the natural, which they dont anyway.

    @ Fifi

    You are right when you say “there’s some real resistance to accepting scientific understandings that overturn conventional understandings”. The problem with the mind/brain issue is that _no-one_ can even begin to understand how quality of experience can _be_ brain function because they are not obviously the same. Not even materialists especially of the eliminativism kind who simple deny the problem. Theres nothing in the make-up of atoms, molecules, neurons etc.. that can explain how or why we have conscious experience instead of being automata. Not even indirectly through emergence.

  36. Roy Nileson 17 Jun 2008 at 6:10 pm

    Evoking the supernatural to show either how or why we have a particular subjective experience hardly qualifies as an explanation.

    Except of course that it will be inevitably argued that the supernatural in toto has been explained by self-revelation.

Trackback URI | Comments RSS

Leave a Reply

You must be logged in to post a comment.