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Ray Kurzweil does not understand the brain

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Re: Ray Kurzweil does not understand the brain

#171

Post by abecedarius »

Kurzweil is reported as equating 25MB of compressed DNA to 1 million lines of source code, which seems several times too low: if I compress the comment-stripped source to one of my own projects, it compresses down to 8 bytes per line of code as defined by sloccount. If we suppose compressed DNA has similar real info rate to my gzip-compressed source, then 25MB corresponds to 3 million SLOC, not 1. If you include blank lines and comments, then more like 5 million.

For another take, http://www.dwheeler.com/essays/linux-kernel-cost.html puts the Linux kernel source at 4 million lines. Can you compile a 25MB kernel? Compressed? (How much of it is 'introns', anyway? This might not be the best example.)

(Not going to touch the argument about applicability. It does seem to me that whenever Kurzweil glosses over details, the closer look always appears less utopian. There are other writers about these ideas who I can read without having to check every assertion, like Anders Sandberg.)

Re: Ray Kurzweil does not understand the brain

#173

Post by jerf »

dhs wrote: post #118
jerf wrote: post #94

Earlier quoted context omitted.

Saying it's NP-complete doesn't prove we can't solve it well enough for simulation. As a physical problem become "pathologically NP", Nature becomes non-deterministic too; it seems unlikely that Nature will make extensive use of a protein that doesn't reliably fold in a certain way, or some small constrained set of ways. See http://www.scottaaronson.com/papers/npcomplete.pdf

Not that I wouldn't like to be as optimistic, too, but Nature does seem to have made enough use of unreliably folding proteins to have come up with BSE, Parkinson's disease, and some others http://en.wikipedia.org/wiki/Protein_folding#Incorrect_prote... >. I'm a big fan of Scott Aaronson, too, btw :-) Here's a pic of him demoing the soap bubbles experiment he refers to in that paper you linked to http://www.scottaaro…

I thought of mentioning that, actually, but figured it would be extraneous. However, if they are all indeed pathological then perhaps we can do our simulated humans a favor and not simulate the pathological path.

Still, as discussed in another comment I made, I seriously, seriously doubt that we will ever simulate any sort of intelligence by raw physical simulation. It just isn't feasible with any realistic computational technique.

Re: Ray Kurzweil does not understand the brain

#174

Post by zoomzoom »

api wrote: post #168
zoomzoom wrote: post #161

Earlier quoted context omitted.

Look - all the talk of the brain as a "quantum computer" seems to be more full of "bull" than the talk of mind uploading and 700 year lifespans. Quantum interactions happen in all matter that we observe, so they happen in the brain. There is not that much more to it. Neural computation depends on neurons and synapses, communicating with hormones and electrical impulses. If we can model the significant algorithms and…

http://en.wikipedia.org/wiki/Philosophical_zombie What if the background stuff that you neglect from your model is where all the interesting stuff happens? Some people see the philosophical zombie as an argument against consciousness being material at all. I don't really see that, but I do see it as an argument against the idea that you can achieve sentience by emulating a coarse-grained approximation of the brain. I…

What if there is no "really interesting stuff"? What if the stuff in the world was all "regular stuff"?

Re: Ray Kurzweil does not understand the brain

#175

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…

Actually, we're not in agreement.

> vastly underestimating the amount of state that is associated with the exact details of a developing organism.

Sir, kindly indicate where Myers makes that point. I read him as going straight into protein folding, and the complex interactions required for the expression of the genome. (I believe you agree that state in the environment that is caused by the expression of the DNA is not information originating in the environment - ie that this is merely magnifying information, as you put it.)

While there is an incredible amount of state created, in the from of gradients and so on, this is directed by the genome...

Or maybe this is our basic disagreement: do you think that an image of a mandelbrot set creates information as it is generated (and that pi creates information as each digit is calculated), or do you think that the information is defined within the algorithm that calculates it? [there are other issues, but just taking this one alone]

So I'm not 100% sure what you mean; please clarify if I understand you correctly.

While there's information in the environment, there's not very much: consider the white and yoke of a chicken egg. Like letters etched in metal with acid, most of the information is in the placement of the letters; the exact nature of the chemical reaction contributes a very small amount of information. Can you indicate why you think there is a great deal of information originating in the environment?

Yes, the heath of the mother can have an effect, but that's if she is unhealthy, and development does not proceed normally. Assuming she's healthy, the specific condition of the mother doesn't determine whether or not a human being is created. Are you suggesting otherwise?

Re: Ray Kurzweil does not understand the brain

#176

Post by api »

zoomzoom wrote: post #174
api wrote: post #168

Earlier quoted context omitted.

http://en.wikipedia.org/wiki/Philosophical_zombie What if the background stuff that you neglect from your model is where all the interesting stuff happens? Some people see the philosophical zombie as an argument against consciousness being material at all. I don't really see that, but I do see it as an argument against the idea that you can achieve sentience by emulating a coarse-grained approximation of the brain. I…

What if there is no "really interesting stuff"? What if the stuff in the world was all "regular stuff"?

Could be.

It sounds like I'm making a new-agey argument against reductionism, but I'm not. What I'm arguing against is overzealous reductionism... the idea that you can get a grainy image of something and quantize it and you're done. You might be able to do that in some areas, but in biology you can't get away with that. Very small causes can be just as important or more important in living systems than very large ones.

To avoid the philosophical zombie problem, I think at the very least we need a solid theoretical understanding of the phenomenon that we are trying to capture. We have to know what we are trying to do, otherwise we do not know how to start to go about doing it or whether we have done it or not. If you want to land on the moon you need to know what the moon is, where it is, and where you are in relation to it.

That means that we need:

1) A quantitative, hard, solid definition of life. Right now what we have is a qualitative phenomenological definition of life as it exists on Earth. I'm imagining a definition of life that's as solid as the thermodynamic definition of entropy or enthalpy. Based on what I've read in this area already, I would say that it's almost certain that a definition of life will be stated in terms of thermodynamics. Google Ilya Prigogine and dissipative structures to get started.

2) A definition of some sort for consciousness. Right now we have basically nothing here... not even a qualitative set of criteria like we have for life. We know that we are conscious, and we suspect that at least some other living things are conscious. We do not know whether all living things are conscious or not. We do not know whether the set of all conscious entities is entirely contained within the set of all living entities or whether something could be conscious but not alive.

IMHO dismissing #2 is chickening out. Dismissing #1 is definitely chickening out. Not answering the questions means you don't know where the moon is and you might be landing in New Mexico instead.

Re: Ray Kurzweil does not understand the brain

#178

Post by randallsquared »

orborde wrote: post #147
randallsquared wrote: post #130

Earlier quoted context omitted.

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

If you think about it, that's evolutionary theory in a nutshell. Organisms don't evolve due to any desire or goal to change; rather, random processes cause mutations, and traits that happen to result in more copies of themselves being made tend to become more common, and that's it. There is no purpose to the changes; they just are, and "better" ones happen to become more common because they duplicate more.

I would argue that this just means that some things and processes, like evolution, do not have a purpose, rather than that their purpose is whatever actually happens. If purpose just means result, then you've defined purpose such that it no longer applies to lots of systems we actually already understand the purpose for.

Re: Ray Kurzweil does not understand the brain

#179

Post by TheEzEzz »

cageface wrote: post #123
TheEzEzz wrote: post #122

Earlier quoted context omitted.

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.

Yes, but what I'm pointing out is that what you are complaining computers fail to have, other physical systems also fail to have! Even a second bucket of water can't predict the first bucket of water! Thus, the fact that a computer can't either is sort of insubstantial to the question of a simulation's utility, no?

Re: Ray Kurzweil does not understand the brain

#180

Post by 10ren »

akeefer wrote: post #87
rsaarelm wrote: post #29

Myers is attacking Kurzweil on the assumption that Kurzweil is actually proposing that the brain's structure should be reverse-engineesed from DNA, which would be intractably hard. Only Kurzweil isn't saying this anywhere. Instead, he seems to be using DNA as a measure for the amount of irreducible complexity that needs to go into a system that will end up with the complexity of a human brain. Basically, we have no i…

The argument Myers is making is that while the DNA might be the input to the system, the total amount of data in the system is that input plus the rules around how that input is interpreted/works. Those rules (for example around protein folding) are currently encoded in biological systems as the laws of physics, more or less, but they're insanely complicated and currently unknown. So the point is that perhaps if you…

So it's a bit like a program, with sequences also selecting a different Turing machine? (which determines how that subsequence is interpreted.)

Because the Turing machine is selected entirely by the sequence (the protein folding caused by the laws of physics is selected entirely by the sequence), the number of possible results (the number of different shapes that could result) is limited to the number of different sequences. That is, the information in the phenome seems to be limited by the information in the genome.

If you think of it as a two part message, with the first part encoding a model, and the second part configuring it, then the DNA can be seen as the configuration, and the laws of physics as the model (which isn't actually coded anywhere like DNA - we'd have to write that ourselves.)

This model is constant over all life, so that DNA from all species (plants and animals) share the same "model" (laws of physics that cause protein folding etc.)

Another example of a two-part message is that the first part is a programming language, and the second part is a program written in that language. For a high level language (esp with libraries), it's obvious that a very short program might do an awful lot; but the true information content is not that program alone, but the total including the language and libraries it uses.

However, and this is my point, I don't believe that the laws of physics have been constructed so conveniently that provide as much assistance as a high level language with libraries. At most, nature may have stumbled onto hacks in physics (like surface tension, interfaces and gradients) and exploited them. Actually, given how long it took to get life started, perhaps it had to find a whole bunch of clever hacks (randomly recombining for billions of years over a whole planet) before it came up with a workable model (that is the model that DNA configure.)

hmmm... we might be able to estimate the information content of the 'model' by how many tries it took to come across it.

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