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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."
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.
Give me Classic Slashdot or give me death!
Indeed, I waded though The Emperors New Mind when it was first published and was very disappointed. As far as I could tell, the argument was something along the lines of "consciousness is mysterious and complex and hopefully non-deterministic. Quantum effects are mysterious and complex and non deterministic. Consciousness is probably a quantum-based phenomenon then".
So I went back to reading Dennett and Hoftstadter.
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?
Do not mock my vision of impractical footwear
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.
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
Which goes to show how people prefer reading material that confirms their already strongly held opinions.
I also read both Hoftstadter and Dennett. The former made a similar mistake to the one you accuse Penrose of making: attaching almost mystical properties to the concept of recursion and the emergence of complexity. Dennett has similar problems, but more than that he has mistaken a model of cognition for a model of conscious experience. He side steps the explanatory gap by simply denying it exists, just as Hoftstadter denies it by promoting the idea that it is simply an emergent property, without being about to explain exactly what the nature of that property actually is.
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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