An existential problem.

[Orlion]

You make it it sound like chemistry does not take the "quantum" into consideration. It has since around 1967

There are many, many, many operations occurring in the brain/body/universe. So much so, that we are discovering more all the time. However, there is plenty of evidence that all this is, in fact, chemical. Why? Cause it deals with matter, of course! We have all ready identified chemicals that make us tired, happy, drunk, depressed, etc. and how various interactions with stimuli will instigate a biochemical pathway that releases or suppresses chemical production (for example, in the dark or absent of light, the body will produce Melatonin which will cause the body to grow tired. This same chemical production will be hindered by the presence of light.)

Anyway, back to the original point: a lot of chemistry is driven by the movement of electrons. The movement of electrons is best described through quantum wave functions. Ergo, saying that something is "chemical" does not rule out a quantum mechanical process.

[Hashi Lebwohl]

Anyway, back to the original point: a lot of chemistry is driven by the movement of electrons. The movement of electrons is best described through quantum wave functions. Ergo, saying that something is "chemical" does not rule out a quantum mechanical process.

I second this. One semester of P-Chem was Quantum Chemistry, which was all kinds of fun let me tell you. I still have the book, too--a great resource from time to time.

Yes, the interconnected nature of our brain gives rise to things that wouldn't normally happen in a small cluster of nerve cells. All sorts of weirdness happens, like Dali paintings or Thelonius Monk music which computers could never compose. We see these unpredictable circumstances arise in the so-called "savant" cases, where people through accident or genetics seem to have amazing abilities despite some severe limitations. People have the ability to see numbers like a landscape or sculpt animals in perfect detail after viewing them only once? If our brains were more computer-like then there wouldn't be strange cases like these and we would all be more similar in nature or temperament...and that would be boring.

[Zarathustra]

Well, computers are electronic, and since electricity is the movement of electrons, and you can describe this movement using quantum physics, then we must have quantum computers ... ?

I'm certainly not saying that chemistry doesn't depend upon quantum mechanics to explain much of its phenomena. And while points about chemistry don't rule out points about quantum mechanics, no comparison between brains and computers has been made on this level, that I'm aware of, because computers aren't built with this level of physics in mind. In fact, Moore's Law has only been able to proceed for so long precisely because we're been able to ignore quantum effects, due to the scale at which computers are constructed. This will change, however, in the coming years as processors shrink to the point where quantum effects will have to be taken into account. But it won't produce consciousness; it will make smaller computers impossible based on current computer architecture. While there is hope for quantum computers that take this into account, rather than face it as a limitation, we're not there yet. Certainly, Murrin's point that a brain is "just a computer" did not take that into account, AFAIK. And given how we still don't know how all the neurons act together in the brain, we're still years away from any quantum mechanical analysis of its structure. I think there's still room here for my point.

[I'm Murrin]

Didn't take what into account? That man-made processors have a lower size limit? That's entirely irrelevant to the fact that the brain behaves like a machine, with inputs and mostly predictable (given an accurate enough model) outputs.
(An accurate model is of course not possible with our current technology.)

[Fist and Faith]

There is no computer command to feel or to value (for instance), because there is no algorithm which codifies feeling or valuing.

Perhaps we have not made a computer command to feel or to value, because we do not know how to write an algorithm which codifies feeling or valuing. That doesn't mean such a thing is not possible, or that we will never figure it out.

[SerScot]

F&F,

P=/=NP may mean such an algorithmn will take forever to compute. Additionally, the proposition of writting an algorithmn for emotion or values may be "non-computable" as Turing defined the term. We don't know yet.

[Fist and Faith]

That's my point. "May mean" and "we don't know yet".

[Zarathustra]

Didn't take what into account? That man-made processors have a lower size limit? That's entirely irrelevant to the fact that the brain behaves like a machine, with inputs and mostly predictable (given an accurate enough model) outputs.
(An accurate model is of course not possible with our current technology.)

It didn't seem that you were taking quantum mechanics into account, which means--if consciousness does actually arise from this level--that no UTM computer could ever be conscious. It's a response to your valid and interesting rebuttal that my position implies dualism (end of last page). If brains are doing something that no computer could ever do, because they work on a different level of physics, then this is how I can maintain my position and not imply some mystical "substance" beyond matter like a spirit or soul.

Now, the claim that brains behave like machines is based on the fact that we've built machines that mimic certain limited actions that we do with our brains. So to say that our brains function like machines when we've built machines to function like brains (in limited fashion) is like saying that we function like characters in a novel, when those characters were written to function like us. Or it's like saying that storms function like computer models, when we've built those computer models to simulate storms. Just because you make an analogue of something real doesn't mean that the analogy works both ways. Storms only behave like computer simulations in as much as we have accurately simulated the storm. In reality, atmospheric phenomena don't really act like a bunch of algorithms in a processor connected to a computer monitor and a graphics card. They act like molecules of air. And we do not act like a machine responding to input through predictable (via some algorithm) output. We act like conscious beings who are aware of ourselves and for whom our existence matters.

[Orlion]

The computing power of computers is directly dependent on the chemical properties of the materials used I only know a little bit (they don't teach such in college courses, and what little they do teach is related to something else entirely). As an example: you'll find that an extremely important material to make computers is gold. And what about those batteries used to maintain cache memory and that clock in your computer? Batteries run entirely on chemical reactions. The screen? The result of of photochemical properties.

That's really the huge difference between computers and organic life... well, that and organic life is considerably more complex and self-replicating.

[Hashi Lebwohl]

I suspect that when quantum computers are actually built, presuming that this is possible at all, a sufficient level of complexity might give rise to consciousness. We will not have the answers to the questions that will raise, unfortunately, especially the ones the newly-sentient computer will ask.

[Vraith]

I suspect that when quantum computers are actually built, presuming that this is possible at all, a sufficient level of complexity might give rise to consciousness. We will not have the answers to the questions that will raise, unfortunately, especially the ones the newly-sentient computer will ask.

I suspect quantum is necessary, but perhaps not...but on its own isn't sufficient. "Physically" I suspect it will need true network/multiple processing...which is not at all like what is called "parallel processing" now.
But maybe not.
What will almost certainly need to change is the software, the way software itself is written.
As things stand, the programming for quantum is quantum algorithms. Which do exist...but they're still algorithms. And I don't think algorithms can do the job.

[Zarathustra]

Vraith, I second the "necessary but not sufficient" point. Quantum computers will open up a new way of computing by allowing more options besides two (i.e. binary, on/off). But this will make calculations faster, not more sentient. I also agree on the points about networked processing, kind of like a mesh network architecture for connecting multiple computers.