To me, this read like Alan Sokal's Postmodernism troll piece. I understand Tegmark is a reputable physicist, but the abstract could have been written by Deepak Chopra after skimming a math text.
I don't get how very intelligent people can hold such views.
Where does the dance go, when the dancers go off stage? The dancers are not the dance, but create the dance. There is some kind of duality there.
Similar for the brain. What it does creates the mind/consciousness. Should that feel like something? Why not?
How does the brain decide on next actions? By simulating/predicting futures and "feeling" which is desired, and acting towards that future. Why would that not feel like something?
The "hard question of consciousness" is not an answer. It is a philosophical device without backing. It is unknown if qualia is actually hard, maybe most learning systems have it. What we do know: it is hard to have intuitions about it ...
But that is the rub, isn't it. How some mind (or system) experiences something is the very definition of subjective. How to measure that objectively?
Imagine somebody makes a mind out of machine learning. Passes the turing test and more. It reports to "feel", ie to have qualia. Is it parroting what it hears/reads from humans? Or does it actually have a feeling when you show it an image of a sunset? At what breakpoint do you place your debugger and inspect if it is so?
A lot of things which we considered subjective were later found to be measurable. I think we should never stop to find an angle from which we can tackle the consciousness problem.
It is tempting to be lazy and criticize this work because it contains a few instances of the phrase "quantum consciousness".
This paper has one purpose: To get people thinking of the brain and information-carrying systems from a physical perspective rather than solely a computer-science or information-theoretic perspective, or even worse -- a biological perspective. Physicists were largely responsible for computer science and information theory, and they will be largely responsible for breakthroughs in biology and machine-learning as interdisciplinary laboratories continue to grow.
Physics is the most sophisticated area of applied mathematics that currently exists. Whatever consciousness is, it will be understood through physics -- because, presumably, that's what it is.
That said, it is interesting to see a consolidated paper touching on common motifs. The brain exhibits many characteristics of any other state of matter; for example, it has phase transitions.
One thing I disliked about this paper is the conclusion is draws from its examples with the gold ring and the pond. They go on to say that information is not persistent in a pond; for example if you write your name on the surface, the energy will be propagated away and the surface will return to a higher entropy state fairly quickly. This is true, but one cannot say that the brain is different solely because of this. The brain is constantly under "external" influence. It is constantly being supplied with fresh nutrients; neurons are constantly being supplied with tugs from their neighbors. If you were to remove all incoming nutrients, the brain would surely collapse as an information processor, too (e.g. death of the organism).
I would go so far as to say that a conscious system requires constant input, and does not necessarily do anything in the absence of any input. This assertion is in direct contradiction to the heuristics ("principles") established in the paper. For example, computers, bacteria, and brains are all computing systems which require constant input.
This part stood out to me in their idea of how philosophy views consciousness
> A traditional answer to this problem
is dualism — that living entities differ from inanimate
ones because they contain some non-physical element
such as an “anima” or “soul”.
I believe this makes it sound like philosophers are actively looking for the soul, or another explanation of consciousness that lies outside of 'physics'.
This might be true for some philosophers, but there are other philosophies to adhere to. More contemporary would be the works of Daniel Dennett or John Searle.
Cartesian Dualism is surely something not a lot of philosophers would get behind anymore.
I understood Searle's "Chinese Room" argument to advocate dualism -- that there's something more to being intelligent than just behavior. Searle says the more is consciousness, but I don't see the distinction between that version of the concept and a soul or "ghost" in the machine.
Searle is actually an advocate for Biological Naturalism, the chinese room was an argument against computationalism (that the brain works like a computer). Though he admittedly does think the brain is a 'biological computer', and they have their differences.
That's how Searle views himself, but one critique of his work is that he can't distinguish his "naturalism" from dualism. It seems so obvious to him that the Chinese Room isn't conscious, but if it can replicate everything a conscious person would do, it might indeed replicate the phenomena of consciousness. How would we know, after all, since those phenomena are not readily observable.
I interpret "soul", "spirit" and such terms as a poetic concept to represent the kernel of being, as in, what defines individuality. If you understand conscience as the flow of conscious states, what defines you should be the persistent aspects of those states, trying to draw a parallel with programming languages, it's spirit would be it's core functions. So, not what kind of information you have or deal with, but how you deal with it.
I just can't understand the search for a metaphysical soul, as it is not an actual search, it's just faith, hope, it's not a reasonable answer or an attempt at one, and I guess a lot of philosophers and poets use the words "soul" and "spirit" with what I said earlier in mind.
Consciousness is a bit like the speed of light: it's defined, not measured. It's not possible to measure the speed of light because we've made this constant the basis of all other measurements. Consciousness is a lot like that: unmeasurable, and the basis of all experience.
In all frameworks there must be some unquestionable property, which defines the framework. For physics this is the speed of light, for life forms it's consciousness.
Your consciousness is only base of your own experience. For other people your consciousness is only hypothesis to be studied.
> In all frameworks there must be some unquestionable property
I would like to study consciousness outside of frameworks where it is unquestionable - just as we can do it in e.g. classical mechanics with speed of light.
Admittedly -- and perhaps obviously -- I'm not a physicist. But as far as I can see, once we've defined length and time in terms of the speed of light, the speed of light is constant, by definition. The speed of light can never change after this, because it would be observed as all lengths/units of time changing.
Consciousness can't change either, because a change in consciousness changes everything that is experienced, so how can you know whether everything or consciousness changed? There's no difference.
Some terms can only be defined in terms of themselves. What's a meter? It's term used to describe a length of measurement equivalent to one meter. What's consciousness? It's a term used by certain life forms to describe what life is.
How can we study something that's always there, and when it isn't there we're not there either? Everyone "experiences" the absence of consciousness in deep sleep, and there's simply nothing there.
I have alluded in other places of the benefits of a meditative practice. One I have experienced is being "awake" in my dreams. Having a continuous stream of consciousness through my nights of sleep.
I am able to control my actions during and the outcomes of the situations I dream about, and fully recall them after waking.
It was inevitable that it was measured to be constant. You need to build a measuring apparatus out of physical matter and use its physical properties to measure things. Use of any reasonable measuring apparatus will have the built-in assumption that c and h are constant, and either particle masses or G is constant, allowing you to measure combinations of lengths, times, and masses.
> Use of any reasonable measuring apparatus will have the built-in assumption that c and h are constant
The speed of light was measured constant by the famous Michelson-Morley experiment, whose apparatus didn't have any built-in assumption about c (nor had anything to do with h).
The Michelson-Morley Experiment showed that light velocity had the same magnitude in different directions.
One metre is defined to be the length of the path travelled by light in a vacuum in 1/299 792 458 seconds. Therefore,
c = 299 792 458 metres per second. The second is defined in terms of the frequency of electromagnetic radiation emitted during a transition between two specific states in a caesium atom. In other words, it's a unit of time as measured on a kind of atomic clock, which by convention is constant.
It's an open question whether a second on a pendulum clock is the same as one measured on an atomic clock for all time, as that depends on G.
>>> Tegmark’s career is a rather unusual story, mixing reputable science with an increasingly strong taste for grandiose nonsense. In this book he indulges his inner crank, describing in detail an utterly empty vision of the “ultimate nature of reality.”
It's a fair question. The quote is one reviewer's opinion. I posted it without explanation as context for the paper.
A more neutral warning is that Tegmark has moved from conventional science towards untestable speculation. That and the fact that he has cultivated funding sources more aligned with the occult than with science has left many of his peers seemingly resentful.
One has to pay attention very closely to Mr. Tegmark's presentations. He will state very eloquently a number of facts, and then slip in subtly a very important fundamental assumption upon which all of his subsequent statements are built.
> why do conscious observers like us perceive the particular Hilbert space factorization corresponding to classical space (rather than Fourier space, say)
I'm surprised this is even considered by an MIT Physics professor. Conscious observers like us do perceive "Fourier space" in colors and pitch. Am I missing something?
There is a long history of pushing the location of human consciousness further and further with technological advances. First it was god, then it was somewhere in the ether, then it was electromagnetic waves, now quantum mechanics. People just can't stand the idea that conscious thoughts are made of matter.
This simply isn't true. You seem to have read the abstract and made assumptions about the arguments of the paper.
Tegmark doesn't focus on the how; he spends the paper building an argument about what properties an observer must have.
It's very easy to call something you don't understand, or reject a priori, nonsense. But at least try to grapple with the argument and a make criticism with substance.
I think the reason for this (common) error is that we can only imagine the world through what it's like in our conscious experience of it. So when we think of some system processing information "about" the world, we're imagining what it is about in conscious-experience terms, which tends to hide what is difficult to explain.
What is it that is difficult to explain? We don't (currently) know of any phenomenon that is like (for example) what a sound sounds like to us.
I feel you have it backwards. That there are observers doesn't seem like much of a mystery: there doesn't seem to be anything mysterious about observers beyond the right kind of computation. The mystery is the qualitative experience of conscious observers, the feel, the what it is like to be, etc.
To me it does. What is an observer? Is it distinguishable from its memory? If not, what do you have to do to a memory to add observer to it?
Can we make a conscious machine? Why not?
Maybe we can by simulating a brain exactly. But can we then figure out what in our model makes the sim-brain conscious? Can we turn it on and off?
Most of our insights into how human mind works actually describe how a philosophic zombie will work. But I am not one and I would like to know what am I.
There are two issues when it comes to consciousness: the experience and the experiencer. If we conceive of these two concepts as ultimately one in the same problem, then there is no issue with focusing on kinds of processing rather than observers as its ultimately addressing the same issue from a different angle.
If you conceive of these two concepts as separate issues, then your target should be the experience rather than the experiencer. If you consider all the features that make up an experiencer (sans qualitative experience), then these features can be cashed out in terms of information processing. The mystery isn't here, but in the qualitative experience.
>Most of our insights into how human mind works actually describe how a philosophic zombie will work.
Only as far as our descriptions of a brain are "local" in the sense that they don't consider global properties of such an information processing system. That is, we can have a description of a system that makes accurate predictions without making any high level statements about its processing. We can conceivably describe the workings of a biological creature without ever (explicitly) mentioning molecules, proteins, cells, DNA, action potentials, etc. Yet if we concluded from this that biological zombies were conceivable (physical systems that behaved exactly like biological organisms just without cells, proteins, etc), we'd be mistaken. But this is the same kind of leap that we make when take the p-zombie argument seriously.
I may be misunderstanding your claim, but otherwise I think the article would actually interest you. Here's a quote from the paper:
"Instead of starting with the hard problem of why an arrangement of particles can feel conscious, we will start with the hard fact that some arrangement of particles (such as your brain) do feel conscious while others (such as your pillow) do not, and ask what properties of the particle arrangement make the difference."
Is that not investigating what makes something conscious (i.e. an observer)?
EDIT: after a bit of reading, this is not intended for non-scientists. The introduction is interesting, but otherwise your time might be better spent reading critiques of this paper instead if you're a newbee like I am. Here's one such critique: http://blog.jessriedel.com/2014/05/13/comments-on-tegmarks-c...
The observer isn't a mystery, I agree. But the original comment seems spot on: if you are describing consciousness as a state of matter, then you're saying something like, "matter inherits a different set of qualities when it's in a consciousness state (as opposed to a solid or liquid state)." If the state change leads to a change of quality, then you're once again proclaiming consciousness as an object with observable qualities rather than a the observer without quality. This is fine if we're talking about an observable consciousness, but then who is that observer?
I agree with the original comment that this paper is nonsense. I'm surprised how many papers are spent discussing consciousness this way. In biological terms, fine. In physical terms, impossible.
I'm not intending to say anything particularly deep. If we could exhaustively list the features of a "conscious observer", every feature except for qualia (the qualitative experience) could be cashed out as some kind of information processing (e.g. knowledge of one's own mental states). And so when it comes to explaining consciousness, the difficulty isn't the observer part, but the qualitative experience part.
>In biological terms, fine. In physical terms, impossible.
But if biology is just physics, then it should be possible in principle. We should encourage people to bring their particular expertise to the problem instead of taking our own conceptions so seriously to the point of actively discouraging ideas that don't fit. I'm happy Tegmark seems immune to charges of being a crackpot.
If consciousness is a physical thing, how can you be so convinced that it is impossible to talk about it in physical terms? Couldn't the difficulty be due to a deficiency in our current explanatory power, as opposed to something more fundamental? What evidence do you have to support that biological talk (about consciousness, or otherwise) is necessarily irreducible to physical talk?
These questions are very interesting and very hard, and dismissing honest attempts to grapple with them rigorously, wrong as they may turn out to be, seems rash to me.
None of us seem qualified to judge this paper as valid or not valid or to say which parts are valid and which aren't and why.
But the only active thing we can do in Hacker News is leave a comment and this article tickles with me enough to want to leave a comment.
I guess the best comment I can leave here is one that avoids the ignorant-about-own-ignorance pitfall of false expertise and just leave a meta-comment about the comments.
