Intelligent Design

Consciousness, Where Even the Easy Problems are Hard

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Over at the New Atlantis Raymond Tallis reviews David Chalmer’s new book The Character of Consciousness. Here is an interesting passage on all of those MRI experiments purporting to capture consciousness in mere brain activity:

But none of these characteristics seems likely to deliver the difference between neural activity that is and is not associated with consciousness, not the least because they all aim to narrow down a phenomenon that is inherently multifaceted. And the approach faces other inherent limitations. For a start, as Chalmers points out, correlation is not causation: even if one identifies some neural feature correlated with consciousness (say, by stimulating a part of the brain and having the subject report being aware of some mental state), it does not follow that this neural feature is solely or mainly dedicated to consciousness. More to the point, even if some of these phenomena do turn out to be truly and uniquely causative of consciousness, none of them would enable us to get a handle on the “hard” questions. As Chalmers candidly points out, “why should [some particular neural feature] give rise to conscious experience? As always, this bridging question is unanswered.”

And then there is this gem:

Indeed, how do any concepts arise out of the inert matter-energy interchanges of physics? Until we are presented with a plausible account of how the concept of “matter” arose out of matter itself, we should be prepared to argue that there is nothing in matter as described by physics that would suggest it could rise above itself, and enclose that which it has risen above in quotation marks. (It is this simple insight — and not anything about how confusing, difficult, or incomplete is quantum physics — that is one of the great challenges to materialism.)

8 Replies to “Consciousness, Where Even the Easy Problems are Hard

  1. 1
    gpuccio says:

    Barry:

    Thank you for the link. Chalmers is definitely an interesting philosopher of the mind. I owe him the definition of the hard and easy problems of consciousness, that I have used so generously in my discussions 🙂

    I’ll try to get this new book!

  2. 2
    mike1962 says:

    Publication date October 28, 2010. How is this a “new” book?

  3. 3

    The idea that “correlation is not causation” is a chestnut put about by exasperated statistics teachers who have to remind their students that when dealing with non-experimental data (e.g. survey data) that just because X is correlated with Y doesn’t mean X causes Y.

    However, it simply does not apply to experimental data, i.e. data in which you manipulate a randomly assigned variable, and this is precisely what is done in most fMRI experiments, indeed in most neuropsychological experiments.

    Not all, and so that caveat needs to be retained when appropriate, but the issue is not that correlation is not causation, but that non-experimental correlation is not causation. Correlations between a manipulated independent variable and a non-manipulated dependent variable can indeed indicate the direction of causation.

  4. 4

    From the review:

    Various alternative theories appeal to neurobiological properties that are less anatomically localized. These include “systems,” such as the one emphasized most recently by Gerald Edelman, in which consciousness arises from “loops” of activity between the thalamus and the cortex. Similarly, Francis Crick and Christian Koch speculated that consciousness might involve a particular sort of cell throughout the cerebral cortex, which has “a unique combination of molecular, biophysical, pharmacological and anatomical properties.” Other approaches focus more on what the neurons are up to than where they are — their patterns, their intensity, their frequency, the extent to which they are synchronous, and so on.

    But none of these characteristics seems likely to deliver the difference between neural activity that is and is not associated with consciousness, not the least because they all aim to narrow down a phenomenon that is inherently multifaceted. And the approach faces other inherent limitations. For a start, as Chalmers points out, correlation is not causation: even if one identifies some neural feature correlated with consciousness (say, by stimulating a part of the brain and having the subject report being aware of some mental state), it does not follow that this neural feature is solely or mainly dedicated to consciousness. More to the point, even if some of these phenomena do turn out to be truly and uniquely causative of consciousness, none of them would enable us to get a handle on the “hard” questions. As Chalmers candidly points out, “why should [some particular neural feature] give rise to conscious experience? As always, this bridging question is unanswered.”

    I would agree about the theory that certain cells are responsible for consciousness. That seems to me to be a shot in the dark and largely atheoretical.

    But the same is not IMO true about Edelman’s re-entrant loops, and, moreoever, Chalmers’ alleged complaint about it does not apply. Edelman’s theory is precisely that no one circuit is “uniquely causative of consciousness”, and there is no reason even a priori to think there would be a single “uniquely causative” loop (or cell). Many things in the world have no unique cause, but a number of necessary causes, and some things don’t even have necessary causes; rather what is necessary is at least one of several different sets of causal factors. And that is the whole point of Edelman’s concept (and indeed of most of modern neuroscience, by which I mean the neuroscience of the last decade).

    To put it simply: there are many ways to skin a cat. There is no “unique” way to skin a cat, and most techniques will have something in common. But there may well be techniques that work equally well yet have nothing in common.

    Why should that not be true of re-entrant loops?

    Especially given both theoretical and empirical evidence for the model?

  5. 5
    Collin says:

    Ms. Liddle,

    Have you read some of Prof. Chalmer’s other works? In this instance he is talking about some of the “easy” problems of consciousness. But if you’d like to read more about what he calls the “hard” problem of consciousness, http://consc.net/papers/facing.html It’s really an interesting concept.

  6. 6

    Yes, I have 🙂

    In fact, I used to think he was right.

    Now I don’t 🙂

  7. 7
    mike1962 says:

    Blah blah blah. The bottom line is, nobody knows what consciousness is. (You’ve got to be one to know one.) And not one single experiment can show that neurons do anything more than correlate with, i.e, inform, consciousness.

  8. 8
    tjguy says:

    Mike,

    I agree with you. You can’t get outside of your own consciousness to study it..

    It is reminiscent of the determinism problem that says all things are deter mined, but if so, then that includes the idea that all things are determined. You can’t get out from under determinism in order to make a meaningful statement or study it.

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