Saturday, March 12, 2011

The Hard Problem: Consciousness


Sidewalk.
fotologic/via flickr
  Is conscious experience locatable in any precise sense in space?
The famous philosopher of mind, John Searle, said, "Not only do we have no idea what consciousness is, we have no idea of what it would be like to have an idea of what consciousness is."
Saint Augustine had an idea: Consciousness is our Soul, and exists by direct connection to the Mind of God. The Catholic Church is willing to accept evolution of the human body, but not the conscious mind or soul. Descartes just posited mind, Res Cogitans in his famous dualism of Res Extensa — i.e. matter and machines including the human body, and Res Cogitans, the conscious mind.
Modern Connectionists often equate consciousness as another emergent property of sufficiently complex computational systems. I worry, since water buckets by the millions pouring water into one another above and below a bucket level threshold for 1 or 0 could be a complex computer. I just have a hard time believing they would be conscious.
Meanwhile, these computational systems are algorithmic and typically classical, so run afoul of my hoped for critique in my blog, "Is the Mind Algorithmic?" that the mind is not algorithmic. Worse, a classical physical system runs afoul of "how does the mind act on matter, when it seems that the state of matter is sufficient for the next state of matter, and there is no way for conscious mind to act on matter anyway, (but see Daniel Dennett's "Freedom Evolves" for a response.) Often we are driven to one or another, brute or subtle form of epiphenomenalism, in which the brain runs the show and consciousness tags along, ineffective in "acting on matter" or having a "responsible free will". Daniel Dennett in "Freedom Evolves" again takes on some of these problems, but not consciousness itself.
My co-blogger, Ursula Goodenough, and Tom Clark take these issues on from a well nuanced naturalist stance, but, pace Tom and Ursula, it still seems epiphenomenal to me - despite their avoidance of the term - for I cannot see in the natural stance what "mind" does or how it does it. And they do not say what consciousness "is". Well, no fault theirs! Searle of the Chinese Room problem, is right: So far, we have no idea what consciousness is, nor even what it would be like to have an idea what consciousness is.
We have had the problem of consciousness for thousands of years, and here I am, about to offer a working hypothesis! Perhaps "fools rush in where angels fear to tread", but, frankly, I don't believe in angels and, foolish or not, I will tread.
  What I will say rests on two simple, but major premises:
First, as I have argued in the past several posts, Is the Mind Algorithmic?, How Can Mind Act On Matter?, and Towards A Responsible Free Will., I think these antique problems in the philosophy of mind just might be open to elucidation given the hypothesis that the human mind-brain system is a quantum coherent-decohering to classicity and recohering partially or completely to quantum coherence. This "Poised Realm" surely cannot happen in any physical system, for the decoherent loss of phase information is not easily recoverable. But the chlorophyll molecule, coherent for at least 7000 femtoseconds when the normal time scale of decoherence is 1 femtosecond, or 10 to the - 15th seconds, is amazing. More, it is thought that decoherence is either prevented or reversed by the evolved antenna protein that wraps the chlorophyll and, in line with Shor's theorem about quantum error correction, may be partially correcting inevitable lost phase and amplitude information. We can test this with mutant antenna proteins.
Second, it seems to be a coherent and consistent interpretation of the Schrodinger wave equation that what is "waving" are possibilities that are ontologically real. This interpretation is radical. As I have noted, Empedocles argued that what is real in the universe are Actuals and only Actuals. Yet Aristotle in various senses, argued for the ontological reality of Actuals and Potentia, and Alfred North Whitehead in the early 20th Century argued similarly that ontologically real Actuals give rise to ontological real Possibles which give rise to Actuals which give rise to Possibles, where ontological reality is both Actual and Possible.
With Whitehead, I am going to assume a metaphysics in which Actuals and Possibles are Ontologically real. One cannot avoid a metaphysics. For Newton and Einstein, only Actuals are ontological real. Quantum Mechanics admits as one interpretation, ontologically real Possibles. Therefore the step to taking seriously an ontological real Possibility may not be as great as we tend to think three centuries after Newton. There are, of course, other interpretations of Quantum Mechanics, from epistemological Possibles, to the Multiple World interpretation of Everett, to Bohm's Implicate Order interpretation. Thus the detailed experimental verification of Quantum Mechanics allows but does not prove, an ontologically real Possible.
Since we have not had an idea about the hard problem of consciousness for perhaps 2500 years, there is no harm in trying the two hypotheses above: Mind-Brain is quantum coherent-decohering to classicity and recohering partially or completely to coherence; and the Possibilities in the coherent or partially coherent states or realms of the mind-brain system are ontologically real.
Then my step is utterly simple: Consciousness is, really is what I just said. Consciousness arises in a very special physical mind-brain system, perhaps in a special subset of neuronal circuits, able to sustain quantum coherence, decohere to classicity (or classicity for all practical purposes to keep some physicists happy), and recohere partially or completely to quantum coherence. The Schrodinger wave equation describes ontologically real Possibilities waving. In the mind-brain system, that is consciousness.
Why in the world should one wish to undertake a radically different metaphysics? Well, we have not understood consciousness, and perhaps this will help. More, if the quantum possible is ontologically real, it may lead to new physics in many places.
The most striking evidence I will adduce for this jump is, in fact, something we all know perfectly well. Ready? Just where is the possibility of my going to the movies? Is the possibility under the refrigerator? Well, no, I looked.
The possible does not seem to be locatable in space in any precise sense.
Now, what of your actual conscious experience, say of your visual field. Is that conscious experience locatable in any precise sense in space? No, we all know and comment to ourselves that our awareness of the philosopher's "qualia", or experiences, is not locatable in space in any precise sense.
I am deeply struck by this parallel, neither Possibilities nor experiences, "qualia" are locatable in any precise way in space. Is it fair to think that this similarity can be an identity with respect to mind-brain? Why not? The similarity does not, of course, prove my claim, but it is striking.
Just because I feel a bit ornery: Where are hopes and fears located? Where is what we imagine? Where is what we intuit?
If we adopt a metaphysics in which both the Actual and the Possible are ontologically real, a new world opens before us, and consciousness can be our direct experience of that real Possible in our mind-brain identity system.
There is another feature of our experience that we all know, called roughly "the stream of consciousness." In my past blog on "Towards A Responsible Free Will." I noted that the state space of the human cortex, idealizing each neuron to be active, 1, or inactive, 0, is 2 raised to 10 raised to the 10th power - a hyper-astronomical number vastly vastly exceeding the 10 to the 80th particles in the known universe. I argued for a partially quantum random walk along trajectories in this state space, and identified our decisions as movement in the Poised Realm to full decoherence, so something classical and specific happens via this acausal decoherence to classicity in parts of neurons, ie neurotransmitter molecules, their receptors and transmembrane channels on dendrites and perhaps axons.
Then in our full lives, our decisions are often, if not always, reflective of many of our decisions taken throughout our lives. Watch a skilled artist paint. He or she chooses where the next brush stroke and color will go, based on enormous experience and a kind of "flow freedom". This seems to reflect a very large number of past decisions along trajectories in neural state space. Or tally your own stream of consciousness. These experiences fit with what I have said and am saying.
Now, can quantum mechanics reach spatially beyond the detailed coherent, partially decoherent, or partially recoherent, or fully recoherent behavior of any single receptor of a neurotransmitter? Almost certainly "Yes". We have not discussed the phenomenon of quantum "entanglement". It is a confusing concept, but, again roughly, if a single photon splits into two lower energy photons that fly off in different directions, since the two were once one photon, the two are entangled. Astonishingly, as Einstein, Rosen and Podolsky realized in the 1930s, if an aspect of one of the two entangled photons is detected, say its polarization, that detection of the first entangled photon instantaneously implies a restriction on, or correlation with, the polarization of the second entangled photon. This has been amply demonstrated by amazing experiments and is now fully accepted. It is believed that no causal signal can be transfered between the entangled photons as that would break Einstein's speed limit of the speed of light for causal interactions. So the correlation one sees is taken as a non-loca feature of Quantum Mechanics.
Via this non-local feature of Quantum Mechanics, in principle, neruotransmitter receptors all over the brain might be correlated, although not directly touching one another or interacting causally at all. Thus, Quantum Mechanics does not limit the range of entangled interactions - even to within the brain of a single individual!
Thus I raise a third, contentious issue: Many of us have had "strange" experiences where distant related experiences between people are correlated across space. We are told to write these off as unscientific. We are told we have many such experiences and only remember the ones that are strikingly correlated. Perhaps. Perhaps not. I have had such experiences associated with the hit and run death of my own daughter, Merit, at age 13. I have never before or since had such experiences. Until we understand consciousness, I am not willing to write such experiences off as mere coincidences that I remember because they were so emotionally pregnant. Maybe. Maybe not. If such experiences were partially quantum non-local events, one would expect them to be evanescent and hard to replicate. Does that prove such experiences are real? Of course not. Are they ruled out? Not in my mind-brain system.
Can one imagine turning the above ideas into a research program? Yes, certainly. I would consider starting with the chlorophyll molecule wrapped by normal and mutant antenna proteins, measure quantum coherence durations in both cases, then try to carry out, at the current outer limit of feasibility, a quantum computation of the chlorophyll plus antenna protein in a cellular organized water environment, where that organization is due to molecular crowding by proteins and other molecules in the cell. Given Shor's theorm about quantum error correction of phase and amplitude information by injection of information into a decohering quantum system, and a model of decoherence from the chlorophyll to the antenna protein, ordered water and an environment beyond, we can attempt to see if the antenna protein can partially suppress decoherence or, more likely I think, induce recoherence. This is almost feasible. It may become feasible in the near future.
If one found that the antenna protein does indeed induce recoherence, we would have evidence that an evolved molecular system can induce recoherence in the face of the inevitable loss of phase and amplitude information from the open quantum "system" to an "environment". That would be a huge step. From it, one could look for signs of quantum behavior in neurotransmitter molecules, their receptors, and transmembrane channels in dendrites. I stress again that this anatomical hypothesis is obviously very tentative.
Is it conceivable that there is evidence for an ontologically real Adjacent Possible? I report a remarkable experiment noted by one of the commenters to a previous blog. The experiment consisted of subjects shown a sequence of emotionally neutral and distressing images. The experiment monitored eye blinks and pupil dilations as signatures of distress. Amazingly, with a probability of false positives reported to be 0.0009, the subjects responded just before the distressing images were shown! Do I believe the results? No. Should they be repeated? Of course. Suppose it is repeatable? What in the world could conceivably be going on?
Well, an Adjacent Possible, if Ontologically Real, would seem to be in Einstein's Special Relativity future light cone, ie more simply, the future. What if we actually showed that we can be conscious of a future Possibility that will become Actual in a moment? Do I believe it? Again, no, of course not, but it is a fascinating experiment and certainly can be carefully repeated.
Just a few more comments. CPT (Charge, Parity, Time) symmetry is violated due to the existence of only left handed neutrinos. This symmetry violation is well established. Thus, time must have a direction. We do not understand time, and no one knows what CPT violation is due to. But the physicists' sensible metaphysics is, with Empedocles, that only Actuals are real in the world. We are not logically bound to this metaphysics, but Newton's success has surely persuaded us: Actuals give rise to Actuals on the billiard table. It is a "crazy" thought, one about which Paul Dirac could well say, "Not even wrong", but in an ontology in which the future has ontologically real possibilities, that future ontologically real possibilities might give a missing physical sense to CPT violation and an arrow of time.
Note that we clearly experience the "flow" of time. How do we manage to experience that flow? Do we make a kind of mental movie of past Actual moments and view it? Maybe. But this movie of the flow of time does not seem to stop abruptly at the present instant. It somehow seems to seamlessly flow into the future. Why? For myself, it seems that the flow of the past flows into future possibilities in my life. Is that true for all of us? Even if that were so, it wold not prove that we are aware of a future ontologically real Possible. Nevertheless, might our sense of the flow of time be via awareness of immediate future real Possibilities? It is just conjecture at this point, but not necessarily impossible. The image and eye blink experiment described above, if reconfirmed and extended, could actually test this radical idea.
I end, having proposed experimental and computational avenues to explore. I am likely to be wrong. But to my utter astonishment, I found myself, in my next blog, "To Be Is To Be Perceived: A Clue To The Quantum Observer Measurement Problem" finding an unexpected use of Shor's quantum error correction theorem that seems able to yield a quantum entanglement of a quantum-coherent-decohering-recohering conscious observing mind-brain system and its quantum environment - yielding decoherence, perhaps to classicity, in the observed environment - like conscious observation in the two slit experiment. We will see that just such an entangled conscious observing mind and its observed quantum environment, is a very common view among physicists. But we have lacked an idea how this entanglement of observing mind and observed environment might arise physically. This surprising possibility, I think, supports the hypotheses that the mind-brain really is quantum coherent-decohering-recohering and consciousness really may be awareness of an ontologically real possible.

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