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Ray Kurzweil does not understand the brain

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Re: Ray Kurzweil does not understand the brain

#121

Post by andolanra »

Confusion wrote: post #106

Myers is wrong, because he overcomplicates. Kurzweil is also wrong, because he oversimplifies (I'm taking Myers's version of argument at face value; I actually suppose the argument was more sophisticated than that). Firstly where Myers is wrong: the human brain ultimately comes forth from a bunch of information roughly equal to 1 million lines of code. If you could reproduce those 1 million lines and set them loose,…

Myers isn't trying to argue that the million lines of code aren't there or aren't important. He's trying to argue that those million lines of code have to run on hardware which is poorly understood at best, and that trying to reverse-engineer the hardware is several orders of magnitude more difficult than trying to understand the original programming. The hardware components don't follow the law of superposition, either, so we can't just look at each element in isolation. The entire thing has to be understood.

Imagine going back to ancient Roman/Greek/Etruscan/&c times and handing them a ream of paper filled with the hexadecimal representation of an x86 application compiled for a Windows environment, and then showed them what it looked like when running. "Hey, look, now you can play videos and music!" Now imagine it was several orders of magnitude more difficult than that, and you're beginning to get the idea.

"If you could reproduce those 1 million lines and set them loose, allowing them to construct a human being..." The exact point he was making was that there's a lot of handwaved complexity in this statement, and that the abstraction "understand human being program, run code" is abstract to the point where it no longer accurately reflects the reality of the situation.

Re: Ray Kurzweil does not understand the brain

#122

Post by TheEzEzz »

cageface wrote: post #48
TheEzEzz wrote: post #43

Earlier quoted context omitted.

I fail to see the connection. No, a computer simulation can never predict exactly what a physical system will do, even in the case of a single particle, due to quantum uncertainty. But so what? If I took out one of your neurons and replaced it with an identical neuron, that new neuron wouldn't do exactly the same thing, again due to quantum uncertainty; nonetheless, its long term behavior would be essentially identic…

That is, neurons and brains are classical objects, essentially immune to the underlying uncertainty they're built on. Absolutely not. Prigogine's work demonstrates that systems far from thermodynamic equilibrium (of which all living systems are an example) are intractably non-deterministic. The issue isn't the underlying quantum uncertainties, it's the macro-uncertainties of the higher-level system. In other words, y…

I didn't mean to suggest that quantum effects were the only source of uncertainty.

If I've got a cubic meter of pure water, I can slosh it around and observe all sorts of interesting effects. I can then model that cubic meter of water with another cubic meter. That second cube won't behave identically. A cubic meter of water has a very high Reynolds number and can have considerable chaotic turbulence (chaotic in the classical sense, not quantum). The exact motion of the water simply won't be the same, no matter how precisely you mimic the 'input' into the system (forced motion of the cube, for instance).

Nonetheless, the second cube is a fantastic way to understand the first cube, and in some way is qualitatively identical, even when the specific motions aren't replicated exactly. This is exactly the same for computational simulations of the fluid. Of course they can't predict chaotic behavior, but for all intents and purposes they can be just as useful as having that second cube of water.

Likewise, a computer simulation of a neuron may never exactly predict what a real neuron will do. Just like one neuron can never exactly predict what another neuron will do. Just like one bucket of water can never exactly mimic another. But who cares?

Re: Ray Kurzweil does not understand the brain

#123

Post by cageface »

TheEzEzz wrote: post #122
cageface wrote: post #48

Earlier quoted context omitted.

That is, neurons and brains are classical objects, essentially immune to the underlying uncertainty they're built on. Absolutely not. Prigogine's work demonstrates that systems far from thermodynamic equilibrium (of which all living systems are an example) are intractably non-deterministic. The issue isn't the underlying quantum uncertainties, it's the macro-uncertainties of the higher-level system. In other words, y…

I didn't mean to suggest that quantum effects were the only source of uncertainty. If I've got a cubic meter of pure water, I can slosh it around and observe all sorts of interesting effects. I can then model that cubic meter of water with another cubic meter. That second cube won't behave identically. A cubic meter of water has a very high Reynolds number and can have considerable chaotic turbulence (chaotic in the…

You're comparing two very different things here though. One bucket of water is substantially like another just as one brain is like another. A brain and a computer model of a brain are two very, very different things, with completely different meta-properties.

Re: Ray Kurzweil does not understand the brain

#124

Post by TheEzEzz »

cageface wrote: post #91
orangecat wrote: post #83

Earlier quoted context omitted.

Proteins have emergent behaviors not entirely predictable from the behaviors of their constituent atoms. Define "emergent". I can believe that a protein's behavior is extremely sensitive to the initial configuration of its atoms and that as a practical matter we can't (currently?) get detailed enough measurements to predict exactly what's going to happen. But without exceptionally compelling evidence I'm not going to…

I suggest you read Prigogine's book if you're really interested but his work demonstrates that the problem isn't having detailed enough information about state, it's the irreversibility of time, which makes physics fundamentally non-deterministic.

What has irreversibility got to do with it? There are cellular automata that are irreversible but obviously deterministic.

Re: Ray Kurzweil does not understand the brain

#125

Post by tbrownaw »

dkarl wrote: post #109
jerf wrote: post #90

Earlier quoted context omitted.

Yes, but it gives you the newborn baby's brain in toto , including its ability to grow up into a normal adult human. If you get to newborn's brain you are 99.9% of the way there from the AI side. By the time we get there, feeding it stimulus will be a relatively simple problem by comparison.

Not if the world is actually more complicated than a newborn baby's brain. Can we simulate a baby's interaction with its mother without simulating the mother's brain?

Yup, wire it up to a baby-shaped I/O package and ask one of your grad students to take it home with her.

Re: Ray Kurzweil does not understand the brain

#126

Post by [deleted] »

10ren wrote: post #50

I'm not so sure about the simulation, but Ray's right that the brain cannot be more complex than the data that specifies it, speaking information-theoretically. A biologist probably wouldn't get this, because he has too much knowledge of how difficult and complex the actual translation is. It's a mathematical idea, like non-constructive proofs, which freak out sensible folk - and rightfully so. ( EDIT no offence inte…

[deleted]

Re: Ray Kurzweil does not understand the brain

#127

Post by JabavuAdams »

10ren wrote: post #50

I'm not so sure about the simulation, but Ray's right that the brain cannot be more complex than the data that specifies it, speaking information-theoretically. A biologist probably wouldn't get this, because he has too much knowledge of how difficult and complex the actual translation is. It's a mathematical idea, like non-constructive proofs, which freak out sensible folk - and rightfully so. ( EDIT no offence inte…

Where is the information describing the machine ABI in the following legal C++ program? "#include \nusing namespace std; int main() { cout Next question: how large is the pre-processor / compiler / linker / runtime, relative to the given program.

The point is that this idea that you can just look at the information-content of the DNA is so dumb it's not even wrong.

It's funny that you should mention (and dismiss) the Ken Thompson hack, because that seems to be a much better analogy.

Even if 100% of our genome encoded the brain, its information-content would be a ridiculous under-estimate of the organism's complexity.

Note that I'm not saying anything about whether we actually need to simulate the brain to achieve AI.

Re: Ray Kurzweil does not understand the brain

#128

Post by jerf »

dkarl wrote: post #109
jerf wrote: post #90

Earlier quoted context omitted.

Yes, but it gives you the newborn baby's brain in toto , including its ability to grow up into a normal adult human. If you get to newborn's brain you are 99.9% of the way there from the AI side. By the time we get there, feeding it stimulus will be a relatively simple problem by comparison.

Not if the world is actually more complicated than a newborn baby's brain. Can we simulate a baby's interaction with its mother without simulating the mother's brain?

We have a world in hand. We're not trying to build a world simulation, we're trying to build intelligences. By the time we get this far, the infant will probably be embodied, and we can use real "mothers". Some speculate that a non-embodied being can never become intelligent.

Bear in mind we are talking about at least 20 years hence, in my mind.

Re: Ray Kurzweil does not understand the brain

#129

Post by 10ren »

KirinDave wrote: post #108
10ren wrote: post #75

Earlier quoted context omitted.

Environment being another source of information was mentioned (in my 2nd paragraph), but interactions that are determined by their starting points don't add information - even if the result looks more complex. This idea (and the comment about the mandlebrot set) is similar to " pi holding all the information in the world" (assuming it's normal, meaning not repeating/regular) http://news.ycombinator.com/item?id=156722…

> Whereas the training data for a neural net is extra information - but in utero, what is the training data that is not a predictable consequence of the genome? For starters, the mother's chemistry which is a function of her DNA and environment. And the mother's physical environment, diet, health, etc. These are things that have no representation in the genome but can radically change brain structure in a developing…

Looks like I placed too much weight on your parenthetical "and themselves"

> interactions between cell types and their environment (and themselves) is a giant information content multiplier

and we're actually in agreement; my first comment included:

> I'm not so sure about the simulation

> The only other source of information is the non-genomic environment - extra-nucleur DNA like mitochondria, and the womb (which is arguably already specified in the genome, unless mother nature has done a Ken Thompson http://cm.bell-labs.com/who/ken/trust.html at some point.)

Re: Ray Kurzweil does not understand the brain

#130

Post by randallsquared »

jberryman wrote: post #113
api wrote: post #65

I'm a life-long programmer who presently works in software, but I studied biology in college... mostly because I wanted to learn about learning by studying how living systems do it. Biological systems are nothing like anything we would ever engineer, and to understand them we must remove our "anthropocentric engineer goggles" and look at them for what they are. Analogies between biological systems and computers, soft…

relevant to your comment is POSIWID!: the Purpose Of a System Is What It Does

That makes the term "purpose" rather useless, doesn't it?
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