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Ray Kurzweil does not understand the brain

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Re: Ray Kurzweil does not understand the brain

#71

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…

"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."

And Myers is saying that DNA is a such a woefully inadequate measurement of complexity that it barely counts as wrong.

Re: Ray Kurzweil does not understand the brain

#72

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…

Just because underlying structure is simple, does not implies that the system is predictable. For example consider the three body problem, it has simple structure yet there are known limitations on our ability to predict its configuration at a later time in future.

Just because a system has a finite description does not means we can predict its behavior at later time!!

The systems such as our brains are extremely chaotic, and even if we were to simulate it and write programs to change its behavior by altering the underlying code bit by bit. It would be akin to moving butterfly wings to generate storms.

also analyzing such a large system would be "at least" an NP complete problem, Assuming we can even recognize a solution [compile and run a modified genome] in P.

Re: Ray Kurzweil does not understand the brain

#73

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…

...we'd need an impossible computer that could simulate years worth of exact quantum-level physics in a cubic meter of space...

...it might take a little more than the ten years to come up with any sensible code with hope of growing into an AI though...

Dude, you are all over the map.

... 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.

At best, you could say it's a measure of the amount of irreducible complexity for an encoding of the required proteins. We don't seem to have a measure of the system, by which I mean the thing that models the relationships and interactions of the proteins (and their components) with each other and their environment.

Re: Ray Kurzweil does not understand the brain

#74
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? ;)

Re: Ray Kurzweil does not understand the brain

#75
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…

> 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 Which would be true if the DNA specification for that particular part of the body was the only part of what specifies the brain. Myers is pointing out that assertion is patently false. The environment of developing creature and the interactions between cell types and their environment (and the…

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=1567225

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? (ex utero there might be an argument, since humans not exposed to language don't develop it; although a group of isolated humans have developed language spontaneously - complex grammatical structures, the whole bit - which makes sense, given the variety of human languages. This supports the idea that language is genetic, or as Pinker provocatively describes it, the language instinct).

EDIT here's a thought experiment to illustrate why predictable interactions don't add information: taking the figure of six billion bits for the whole human genome, this means it can specify 2^6,000,000,000 different genomes (a lot). You can imagine changing one single bit, and all those complex interactions leading to a slightly different human phenome. Most of the possible phenomes wouldn't be a living human, or even anything recognizably human (or living). But the crucial point is that you simply can't specify any other phenomes (apart from those 2^6,000,000,000). You've changed all the bits - what else is there left to change within the genome?

Re: Ray Kurzweil does not understand the brain

#76
post #63

Earlier quoted context omitted.

> 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 Which would be true if the DNA specification for that particular part of the body was the only part of what specifies the brain. Myers is pointing out that assertion is patently false. The environment of developing creature and the interactions between cell types and their environment (and the…

Is this sort of like having a pre-processor and system code to get a program loaded, linked and running?

Maybe, if you consider the pre-processor to be, well, reality...

Re: Ray Kurzweil does not understand the brain

#77

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…

Just because underlying structure is simple, does not implies that the system is predictable. For example consider the three body problem, it has simple structure yet there are known limitations on our ability to predict its configuration at a later time in future. Just because a system has a finite description does not means we can predict its behavior at later time!! The systems such as our brains are extremely cha…

Thing is, human DNA seems to grow into human babies most of the time, yet at molecular level the environment where it grows is a random, chaotic mess. The rough physical properties, like temperature, and the general chemicals around are stable, but beyond that things are constantly moving and sloshing around in a very unpredictable way.

The idea with the three-body problem is that after some time has passed, we have utterly no idea where the bodies have ended up. Ova don't grow into random jumbles of cells, most of the time they grow into babies.

It takes a lot of very specific information to grow into a baby instead of some entirely different arrangement of proteins. So either the environment needs to be feeding some rather specific controlling information that makes most ova grow into normal babies, or the cellular machinery itself has a system which compensates for external disturbances and constrains the design to mostly what the DNA directs it to be. As far as I understand biology, it's mostly the latter case.

Re: Ray Kurzweil does not understand the brain

#78
post #20

Kurzweil is a brilliant scientist. Calling him a Deepak Chopra is just stupid. He's out of his depth is all. Also, I wouldn't bet against him building an AI that for all intents and purposes appears to be conscious. Full-human simulation is another thing, but with that we are all out of our depth, and it's pretty likely that a conscious computer would be quite capable of understanding it better than us.

"Calling him a Deepak Chopra is just stupid" That's not much of an argument. He plays on the standard things that all religions play on: the promise of some form of immortality, which instinctively plays on the fear of death; claims that the near future will be radically different than the present; etc. His extrapolations of exponential growth are not entirely unfounded but he applies the same logic to everything tha…

I agree that cults of personality are bad things. But dismissing someone as an evangelist and overrated isn't much of an argument either. It trivializes his very real and important accomplishments, and conveniently allows you to dismiss all of his ideas without looking at them on their individual merits. In short, ad hominem, and unwarranted.

Kurzweil has several functioning products that would have fallen into the mess you dismiss as nonsense two decades ago. Is he wrong on a lot of things? Yes. But so is any other engineer looking for things that haven't been done before. Even if Kurzweil has a spell where he does nothing of any merit for a decade (which has yet to happen) I'll still confidently say you're foolish to rule him out as a crank. He's earned his right to dream aloud.

Re: Ray Kurzweil does not understand the brain

#79
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…

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)#Hot_patching) over 3+ Billion years.

Edit: To continue the analogy the boot loader has been lost to time (or sacrificed to free up memory), so getting a working system requires copying not just source code, but also much of the current state of the system.

Re: Ray Kurzweil does not understand the brain

#80
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? ;)

well, if you're going to use that as a baseline you should also factor in that the rate of advancement is exponential. so maybe 10?
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