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Does Quantum Theory Explain Consciousness?
astroengine writes "Quantum theory is often seen as the root cause of unrelated, mysterious phenomena. Take consciousness for example. British physicist Roger Penrose recently argued 'that we will need to invoke 'new physics and exotic biological structures': rewriting quantum theory to make sense of consciousness.' But why do this, especially as there is no apparent causal link between quantum mechanics and the conscious mind? There appears to be a very basic logical fallacy here that even the most prominent physicists seem to be making."
Care to state it?
Quantum Mechanics: The dreams stuff is made from...
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By "recently" you mean "in the previous century"? He's been arguing this since his book "The Emperor's New Mind" in 1989. Maybe he has some new ideas, but your summary doesn't tell..
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He wants the brain to be non-computable, non-simulatable. In short, he wants it to be magic. He has no real justification for his position.
Consciousness is weird. Quantum theory is weird. Therefore quantum theory must explain consciousness.
That's essentially the argument here, and it's pretty easily seen as fallacious. There's no actual evidence that consciousness requires quantum mechanics, besides the trivial fact that our brains are chemical computers and chemistry requires quantum mechanics.
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People want to be an uncaused cause. That's what the concept of free will boils down to. The will can cause things, but itself is not caused by anything. If it were caused, it wouldn't be free. Of course, this would make any learning impossible. Either the will is a part of the chain of cause and effect, and therefore not free, or the soul (or whatever you believe to be the seat of consciousness) can never learn.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
This place is full of Quantum; it's everywhere you look
It's in the halls of Physicists, and pages of a book.
"There has to be a fallacy!" the comment summarised,
And if we care to challenge that, we aren't very wise?
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Professional Neuroscientist here... In fact, I'm recording from a sensory neuron that is partially responsible for the conciousness of an awake behaving mouse right now while browsing slashdot.
There is no reason to think that quantum physics has anything to do with the nature of conciousness. It is not useful to explain free will, or the illusion of free will, of the qualia of objects, or the steadyness of perception on a background of constantly varying spike rates in the brain.
Perhaps the best, short, free, relatively recent summary of the field was written by Christof Koch and Francis Crick, A Framework for Conciousness, and is available here : http://papers.klab.caltech.edu/29/1/438.pdf
I also have a little essay on the nature of free will on my blog here, if interested. http://brainwindows.wordpress.com/philosophy/philosophy-the-science-of-free-will/
Ok, can someone explain to me how consciousness is represented mathematically? I'm not aware of any theorem that proves you can't have consciousness on higher scales unless it occurs at the quantum level. Mostly because consciousness is usually dealt with as an abstract topic.
A: No.
Signed, God.
"Flyin' in just a sweet place,
Never been known to fail..."
New rule for Science Journalism: If your article can be summarized as "No.", don't write it.
If a a man disagrees in the forest, where his wife cannot hear him, is he still wrong?
"Flyin' in just a sweet place,
Never been known to fail..."
Kind of a strange Slashdot topic since as pointed elsewhere Penrose has been working on this since 1989!
Meanwhile bear with me for a mini rant, in that Submitter dived right into a topic covered by some 50 books, by taking a simplistic double quote of Roger Penrose, famous British physicist, recently argued "that we will need to invoke 'new physics and exotic biological structures': rewriting quantum theory to make sense of consciousness," Brooks writes. (Which he then dismissed as disappointing.)
Meanwhile, back at the more erudite book level, let's see some of what's out there.
Pleading rustiness on the original Penrose text, Douglas Hofstadter has been working for 20 years on analogy-based thinking. To get to your question, he calls the electrons and cells and even small neurons little billiard-ball-like stuff that "careens around in a careenium". Then from a second story window, you don't see those individual balls anymore, nor does any one matter. But the holistic big level then becomes consciousness as a "emergent" property that you just can't dissect past a certain point.
On another tack, Stephen Wolfram of Wolfram Alpha fame put another 20 years at about the same time period doing computational pattern science developing the idea that within perfectly special cases in what otherwise look like simple rules, fantastic complex structures simply emerge "out of nowhere". Yet the trick is that they have to be computed, and no fancy equation quite produces the whole result in one sweep - some data absolutely requires the raw minimum iterative processing. He called this something like the law of irreducibility. For consciousness, this means that there are limits to genius, and cavemen can't make cars because it simply takes a raw amount of pre-processing to produce the context that pushes forth an idea. Past that absudium example, it also means for non-geniuses that you can't know why cattle won't go into a vaccination ramp until someone else discovers that cattle hate shifts in light intensity and the ramp looks like a big cave.
My first Journal Entry ever, in 8 years! http://slashdot.org/journal/365947/aphelion-scifi-fantasy-horror-poetry-webzine
Well, what a blast from my college past. I vividly recall all the late night manic chat sessions trying to decode Patricia and Paul Churchland's Neurophilosophy and Daniel Dennets Conciousness Explained.
Anyway, after years of rumination, to me it's clear that:
Quantum mechanics are definitely a part of neurobiology, and hence a critical building block of conciousness. We couldn't think without quantum mechanics. But plants couldn't photosynthesize without quantum mechanics either.
The quantum mechanical properties of neurophysiology apply just as much to clams as it does to humans. And it's just as applicable to those in a coma as to those engaged in a peak experience of some sort. So quantum mechanics definitely don't explain the conciousness of humans and in lesser degrees of other species.
Conciousness is an emergent property of the brain. Most of our evolutionary ancestors weren't concious in the sense we mean it today. Our massive brains are evolutionarily adaptive. Humans pay a big biological cost in having these big brains; very difficult childbirth, very long period of helpess infancy, wide pelvises to accomodate these giant heads, and a whole lot of extra calories and oxygen needed. But we're obviously breeding like rabbits as a species, and the primary limitation on further explosions of population are conciousness-driven (deciding not to have children, and having developed the means to do so).
Conciousness is, pretty much by definition, a really thorny thing to think about and almost perfectly designed to drive philosophers and cognitive scientists into mental loops. Since conciousness can also be described as self-insight, you get into a deep virtualization question in trying to have accurate insight into how you have insight :)!
So the trickiest part about conciousness is figuring out our own conciousness! It's a lot more easy and productive to try and consider someone else's conciousness than our own. Thinking about our own conciousness can easily get to the "eye of the universe question" - even if one has a good biological theory of conciousness, why do *I* have an experience of unique selfhood? That winds up being one of those unsolvable Big Questions, like "why is there something instead of nothing." Whether the existence of existence is explained via the Big Bang or theology, there's still the unanswerable question of what was the first mover. What started the cosmological ball rolling for there to be a universe in the first place?
Well, that was my moment of peak nerditry for the day! I'm going to go kiss a pretty girl for a while as penance...
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Tall Aussie guy, long hair, wears leather jackets, sings a mean Zombie Blues*. Chalmers, who's a philosopher, and Stu Hameroff, an anesthesiologist, started a series of conferences at the University of Arizona on "Towards a Science of Consciousness" a decade or two ago; they alternate between Tucson and Somewhere-outside-North-America, and attract a mixed crowd of neuroscientists, consciousness researchers, philosophers who talk about phenomenology, FMRI imagers, tourists (e.g. me), and a few newagey people and random cranks. A few years ago, there were two "Science and Consciousness" conferences in Arizona around the same time - the scientific one in Tucson, and the Deepak Chopra one in Phoenix**.
Hameroff's done work with Penrose on things like quantum effects in microtubules (which are brain cell parts that are small enough to actually have quantum activity going on, though it's a very long step from saying "quantum noise might be affecting chemical reactions a bit" to "Woo-woo! Consciousness is, like, Quantum, man!". I can't say I really understand Stu's arguments about the connections, because while I know a certain amount of quantum physics and biology and philosophy, I don't do neurology or brain cell structures or phenomenology, so the couple of conferences I got to were interesting and a very steep learning curve.
From one perspective, either the world, and therefore consciousness, are entirely deterministic, or else they're not. (Deterministic doesn't mean calculable - Heisenberg among others make it very clear that you can't really simulate the universe using machinery smaller than the universe - but from a philosophical standpoint it doesn't matter if humans can predict what you're doing to do, it just matters whether you've got free will about it.) If you'd like things to be non-deterministic, physics doesn't give you very many ways to hook that into the world, and you're pretty much stuck with quantum mechanics.*** Does that mean that quantum entanglement is involved in any of the processes, particularly between neurons that aren't directly adjacent to each other? Not necessarily (IMHO, probably not.) Does it mean that a non-physical spirit can grab onto some molecules and shake them around in ways that translate up to conscious thoughts, or does it just mean that the chemistry's a bit noisier because God's playing dice with the Universe but your consciousness is still fundamentally a materialist process?
* "Zombie" is a term of art, referring to a hypothetical person or machine that reacts externally as if it were conscious, but doesn't actually perceive qualia the way conscious beings claim that we do, so for instance it can tell you which ball is the red one or the green one, but doesn't experience redness or greenness. ** So of course Chopra caught on to this, and has been one of the sponsors of the more recent round or two of the scientific conference, and he and Hameroff have put out one or two popular press articles together. There are a number of meditation people who come to the conference, but they tend to be the serious "Here's what an FMRI shows about blood flow in your brain while you're meditating" folks, while the cranks are more likely to have opinions about quantum. *** There are some theories of quantum mechanics that say it's still deterministic, just with underlying hidden variables that we can't observe or measure, but it's been too many decades since college physics for me to remember if those got disproved or are still around.
Bill Stewart
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