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Ray Kurzweil does not understand the brain

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Re: Ray Kurzweil does not understand the brain

#131

Post by cageface »

TheEzEzz wrote: post #124
cageface wrote: post #91

Earlier quoted context omitted.

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.

It has to do with entropy and thermodynamics and the fact that living systems are so far removed from thermodynamic equilibrium that they generate unpredictable, emergent behaviors.

The math behind is pretty gnarly but if you want to understand it I recommend his book: http://www.amazon.com/End-Certainty-Ilya-Prigogine/dp/068483... .

A CA is not a good model for this.

Re: Ray Kurzweil does not understand the brain

#132

Post by jacquesm »

jasongullickson wrote: post #74
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…

Getting close would take an advancement in computer technology of the magnitude of the transition from vacuum tubes in individual boxes to a 32nm Core i7. ...so about 35 years? ;)

Or 500, or 10,000, who is to know. The problem is that the way the brain seems to be organized is around very simple (at face value) processing components that operate at a ridiculously low frequency in a massive parallel manner that we programmers can only dream of, at a power budget that would make Ebenhaezer Scrooge look very happy indeed.

If 35 years (according to Henry Makram, linked below it's only a decade) was all it took then we could simulate the brain today at a reduced speed and get meaningful output, after all, all you'd have to do is slow down the inputs accordingly.

We're as far away from having a universally teachable computer (not programmable!) as we were in the early 70's when true AI was only about a decade away.

Some interesting reading about the 'state of the art':

http://spectrum.ieee.org/tech-talk/semiconductors/devices/bl...

http://bluebrain.epfl.ch/

http://www.technologyreview.com/biotech/19767/

Re: Ray Kurzweil does not understand the brain

#133

Post by jongraehl »

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…

"the brain may very well be a quantum computer"

This is the minority view in neuroscience.

> In quantum terms each neuron is an essentially classical object. Consequently quantum noise in the brain is at such a low level that it probably doesn't often alter, except very rarely, the critical mechanistic behaviour of sufficient neurons to cause a decision to be different than we might otherwise expect... —Michael Clive Price

Re: Ray Kurzweil does not understand the brain

#134

Post by akeefer »

ewjordan wrote: post #119
akeefer wrote: post #87

Earlier quoted context omitted.

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…

1) An estimate of complexity is what it is - an estimate of complexity. It's not a claim that the way to achieve AI is to figure out the details of the particular encoding that nature ended up using, so the precise nature of those rules is not something we care about. 2) While it's true that those runtime rules (which we can kind of consider as the "interpreter" for our DNA) are extremely complex, this has almost zer…

I think the article's original point (and mine as well) was that considering the size of the code (i.e. the DNA) as a measure of the complexity of the task is totally disingenuous when you don't have (to use your analogy) the web server, the libraries you're calling, the parser/compiler/linker for the language, the operating system for the server along with its drivers/TCP stack/etc., the processor it runs on, the mother board, or the storage. In order to turn 10,000 lines of code into a web application, you need millions of lines of code (and Verilog or whathaveyou) in terms of infrastructure.

The problem for AI is not just encoding the DNA, as it were, it's in building all those other pieces around it. Estimating the complexity of building a software brain based on the amount of information in DNA is like estimating the complexity of building a web application using 1950's hardware. "It's only 10,000 lines of code! How hard can that be? All we have to do is write the code, plus the frameworks, programming language, and operating system, plus do all the hardware design."

Re: Ray Kurzweil does not understand the brain

#135

Post by jacquesm »

ljscharen wrote: post #117
ewjordan wrote: post #112

Earlier quoted context omitted.

DNA is not a program-- it is a molecule, and one that may very well do things at the quantum level that are biologically important. Sure, but Kurzweil's claim is merely that if DNA can encode everything the brain does with N bits of information, then regardless of how the DNA behaves, we have at least a loose estimate of the level of complexity in the brain. I don't necessarily think that he's right that AI will firs…

Sure, but Kurzweil's claim is merely that if DNA can encode everything the brain does with N bits of information, then regardless of how the DNA behaves, we have at least a loose estimate of the level of complexity in the brain. The problem is that DNA is not sufficient. Organisms don't grow from naked DNA in a vacuum; the DNA is always contained within a cell which is enclosed within a more complex bio structure (eg…

For the moment we seem to have enough trouble modeling (relatively speaking, to the brain) simple proteins reliably.

It's quite a leap of faith to make these statements about the technological future with so little in terms of progress to show in these fields for the last decades. I think the most impressive a-life demos are now almost 10 years old, the best we can really simulate is (drumroll) a cockroach. And personally I think that's a milestone achievement because it means that at least we have a principle that works.

Going through the DNA route to get to a working brain seems to be a very roundabout way of getting there, it will require all of the embryonic mechanisms to be modeled accurately as well as something like the first several years out of the womb before you'd know if you had created something insane or something resembling intelligence.

Assuming you'd recognize it as intelligent even if you succeeded, there may be more ways of being intelligent than we know about.

Re: Ray Kurzweil does not understand the brain

#136

Post by sliverstorm »

api wrote: post #88
Retric wrote: post #79

Earlier quoted context omitted.

I think DNA is actually best described as a 1970's era binary in a running mainframe. It rewrites its own source code depending on outside information. And in order to understand what happens you need to look at a core dump that includes all the interesting bit's floating around and attacking/enveloping the DNA. PS: Don't forget this source code has been hot patched ( http://en.wikipedia.org/wiki/Patch_(computing)#Ho…

Not too bad, but sort of like trying to describe an elephant as a bunch of balloons and a water hose glued onto a bail of hay on a table. I also dislike those sorts of analogies because they are loaded with aesthetic value judgements that do not apply. Programming code that looked like that would be ugly. The genetic system is beautiful and elegant.

> The genetic system is beautiful and elegant.

Only because you don't have to maintain it

Re: Ray Kurzweil does not understand the brain

#137

Post by [deleted] »

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…

[deleted]

Re: Ray Kurzweil does not understand the brain

#138

Post by canadaduane »

itistoday wrote: post #69
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…

but Ray's right that the brain cannot be more complex than the data that specifies it, speaking information-theoretically. You're conflating two very different concepts of complexity here. One is the complexity of a static state of information, and the other is the complexity arising from dynamical systems. As roadnottaken pointed out, fractals are perfect examples of systems that are described by very "simple" formu…

The objective is to simulate the real-time activities of the brain, not the evolutionary-time activities that were and are acting on the brain.

Continuing from your extension of the fractal analogy, the former is more like an "iteration of the Mandelbrot" while the latter is "how to generate the next frame".

We do not need to know how our human-precursor brains worked, nor do we need to know what our human-successor brains will be like to successfully simulate current-human-brain intelligence.

It seems plausible to me that we will be able to understand how to simulate the functions of the brain without necessarily simulating the physical universe and its remarkable evolutionary unfolding--which seems to be the ultimate level of complexity and one that I agree is far beyond us.

Re: Ray Kurzweil does not understand the brain

#139

Post by Confusion »

andolanra wrote: post #121
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, eit…

  He's trying to argue that those million lines of code have
  to run on hardware which is poorly understood at best
He may be trying to argue that, but that isn't the central thesis of what he is arguing. His central thesis is that

  [The brain's] design is not encoded in the genome
and that's just patently false. There's only one single blueprint for the brain and that's the genome. That the ways in which the blueprint is being read, interpreted and carried out are not in the genome does not detract from the fact that the genome is the blueprint. His arguments support the thesis that a blueprint is not enough. The objections to Kurzweil that I list are a summary/rephrasing of the arguments Myers provides. But he starts out by saying "No, that isn't the blueprint" and none of the arguments support that thesis.

Re: Ray Kurzweil does not understand the brain

#140

Post by alisey »

heyadayo wrote: post #107

My programmer's understanding of the argument is this: Even if you could reduce the brain to some sort of bytecode, an interpreter is still necessary to run that bytecode. For instance, a python program might be a few bytes, but the interpreter is still a few megabytes. Yet both are necessary to run the program. Who knows how large a brain bytecode interpreter is going to be, but probably very large.

But you don't need to write the whole interpreter to understand how that small python program works.
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