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Ray Kurzweil Responds To PZ Myers
On Tuesday we discussed a scathing critique of Ray Kurzweil's understanding of the brain written by PZ Myers. Reader Amara notes that Kurzweil has now responded on his blog. Quoting: "Myers, who apparently based his second-hand comments on erroneous press reports (he wasn't at my talk), [claims] that my thesis is that we will reverse-engineer the brain from the genome. This is not at all what I said in my presentation to the Singularity Summit. I explicitly said that our quest to understand the principles of operation of the brain is based on many types of studies — from detailed molecular studies of individual neurons, to scans of neural connection patterns, to studies of the function of neural clusters, and many other approaches. I did not present studying the genome as even part of the strategy for reverse-engineering the brain."
Clearly, this dispute should be resolved by a poll.
It's the only way to be sure.
Living With a Nerd
This whole discussion reminds me way too much of the million partisan pundit sissy fights that rage endlessly on the internet. If I wanted to see two guys argue about what the other did or didnt say, I would gladly head over to DailyKos or BigJournalism and drown myself in their pedantry. This is slashdot; please save the inanity for the comments and at least give us stories that have meaning!
Myers may have been focused on the "reverse engineer from the genome" argument but really the main issue is whether Kurzweil is within a few orders of magnitude of guessing the right level of complexity necessary to simulate a brain. The gist of the Myers argument isn't so much about genomics and ontogeny as it is about the emergent complexity of inter-related systems and I think the real nugget there might be something like: "We could model a brain but that wouldn't mean we modeled a mind. To model a mind you need to model a great deal of the environment the mind lives in... and that is many many orders of magnitude more complex."
For the record: I hope Kurzweil is right but I rather doubt he is. I don't think he's wrong about how powerful machines will be in 2050 I think he may be wrong about whether those machines can simulate a mind well enough because I really wonder if the complexity of a mind is actually a superpolynomial problem due to the hyper connected-ness of a mind and its environment.
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Myers, who apparently based his second-hand comments on erroneous press reports (he wasn’t at my talk), goes on to claim that my thesis is that we will reverse-engineer the brain from the genome.
So put your speech up on your site, all I can find are videos from previous summits. TED seemingly posted videos as they happened and therefore we could openly debate them. Summits are great but not everyone has the time or resources to attend them. I would suggest you move towards a more open format of disseminating your ideas and the very specific and lengthy details about them. I'm not going to buy a book on futurism and wade through it for the details you provide about neurobiology and I don't think PZ Meyers would do that either.
I mentioned the genome in a completely different context. I presented a number of arguments as to why the design of the brain is not as complex as some theorists have advocated. This is to respond to the notion that it would require trillions of lines of code to create a comparable system. The argument from the amount of information in the genome is one of several such arguments. It is not a proposed strategy for accomplishing reverse-engineering. It is an argument from information theory, which Myers obviously does not understand.
Well, frankly, I don't understand it either. You're applying information theory to lines of code ... and that just doesn't make any sense to me. I haven't heard of it. I haven't heard of anyone say "theoretically could be reduced to x lines of code." I don't know why we're talking about information theory when we're talking about simulating the brain or even understanding the brain.
The amount of information in the genome (after lossless compression, which is feasible because of the massive redundancy in the genome) is about 50 million bytes (down from 800 million bytes in the uncompressed genome). It is true that the information in the genome goes through a complex route to create a brain, but the information in the genome constrains the amount of information in the brain prior to the brain’s interaction with its environment.
So first it was information theory on the genome and now you're on about compression of the genome. Great, you've applied theoretical limits to lines of code in order to describe a complex biological system and then argued that due to redundancy we can reduce it to 50 million bytes. And what did that buy us exactly? Look at how many lines of code we've devoted to simulating a single neuron or synapse ... and it's not even a complete and accurate simulation. Your theoretical limits are amusing but pointless ... to further apply your 'exponential growth' of the lines of code we can program is further amusing.
Kurzweil is a futurist with just enough knowledge to sell people. His exponential growth to a singularity and proof of it doesn't do him much good when he doesn't understand the complexity of the brain and then applies theoretical limits to that from other disciplines. He's free to keep preaching, I just question at what point people will give up on him. If he dies soon and pulls a L. Ron Hubbard what sort of cult then will we have on our hands?
My work here is dung.
I said that we would be able to reverse-engineer the brain sufficiently to understand its basic principles of operation within two decades, not one decade, as Myers reports.
We don't have more than a rudimentary understanding of how the brain works, or even what Consciousness is.
Free Martian Whores!
Ray Kurzweil / PZ Myers slash fiction.
Go on, try to tell me that's not brilliant.
The major flaw I can see in his response (which I think was addressed by Myers) is
but the information in the genome constrains the amount of information in the brain prior to the brain’s interaction with its environment.
He even underlined it. The problem is that the brain doesn't just spring into existence fully formed and THEN get exposed to the environment. The brain starts out as a few cells and is constantly exposed to the environment as it develops. I think this was a major point in Myers response and RK just blew right past it.
Theres a much more basic assumption that is wrong.
Data needed to create item != lines of code needed to simulate item
I can specify the production of a ceramic rod in a 20kb text file. "get mud, roll into cylinder 10cm long, diameter 1cm, bake to 1500 degrees"
This does not mean that I can write a program to simulate it's behaviour in 20kb. At what stress will it fail? If I twist it how many pieces will it shatter into?
the data required to build a brain is only weakly correllated to the size of a program that might simulate its operation.
If you're going to stand up and tell people you think someone else is wrong and hasn't properly understood the problem, make sure you're not basing your opinion on a second-hand re-telling of what the guy might have said. I'm off to tell PZ Myers that Alan Cox claims to have documented a cold fusion powered time-travel device in the comments of the -ac branch kernels.
When are we human? Abortion hinges on this, WHEN is the foetus a human being with a human brain. Is there some magic moment the brain switches on OR are we a bacteria that evolves rapidly into a complex life form?
Can it be that the brain "knows" the human body and how to operate it because it "grew up" with it? We imagine a robot being build typically on a long assembly line and only at the last moment the head is connected and the robot switches on. Could a brain instead function as a very small simple "cpu" that has more and more peripherals (but small ones) learns about it when they are still simple and then grows familiar with them as they and itself grow? Are WE created from a single egg, not the just he body but the WE, the spirit, the bit that makes us, makes any animal able to think? It would explain low level functions far more. A full grown heart is hard to control, but when you can get to grips with it when it is still just a few cells, that makes a lot more sense. Even fits what we know of brain cells being able to learn how to fly. Start simple, then add more complexity rather just plump some brain cells into a 747 and asking it to fly to Hong Kong and boink the stewardess.
But building something like this? Fat chance. We use rat brain cells for a reason. Even building an AI that could teach itself to fly is beyond us. We can build AI that can fly but NOT AI that can teach itself to fly. Not even in very simple environments. That says something.
I think the old "And the egg starts to divide" bit is a bit more complex then we think.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
PZ is no idiot, but he does have a tendency to lash out at those who are, and occasionally also at those who aren't. I used to post on his blog fairly often, until it degenerated into a far-left echo chamber when he couldn't be bothered to require civility from his commenters. I also wouldn't describe him as being one of those high school pricks that you mention, although he certainly does tolerate and cheer on the ones who frequent his blog.
Kurzweil may or may not be right about the feasibility of AI, but it's a field he's worked in for decades, and one in which PZ has only tangential familiarity.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
is right. Myers criticism may be off the mark but Kurzweil's speculation about brain design, like some much of his other speculation, is bullshit. His basic argument in the blog post is that the amount of information in the human genome constrains the amount of information (and the complexity) required to design the brain. This thesis is wrong on a bunch of levels but let's take the most obvious. The amount of information in the genome is the amount of information that the "body" (to simplify) requires to replicate or create parts of itself. The amount of information required is relative to the machinery which is going to interpret it. There is no reason to believe we are dealing with a Turing machine here where the amount of bits required for a program to perform a function is going to be more or less consistent across languages and platforms (assuming similar complexity of the code). The machine interpreting the bits matters. So while the body may only need "50 million bytes" to create itself we may need many, many more millions of bits to specify how to build it. Just consider the complexity of protein folding.
More dubious statements follow:
"The goal of reverse-engineering the brain is the same as for any other biological or nonbiological system – to understand its principles of operation. We can then implement these methods using other substrates other than a biochemical system that sends messages at speeds that are a million times slower than contemporary electronics. The goal of engineering is to leverage and focus the powers of principles of operation that are understood, just as we have leveraged the power of Bernoulli’s principle to create the entire world of aviation."
This completely begs the question of whether it can be replicated in another substrate. He just assumes that it can be done and by doing so he already assumes a model of the brain that could be (and is most likely) wrong. The brain is clearly not a Turing machine. That's not say it is not another kind of "computer" (for some expanded definition of computer) or follow mechanistic principles however. Assuming the brain is like a Turing machine (which Kurzweil implicitly does) is one of the biggest obstacles to developing real AI.
Speculation of Kurzweil kind does not belong in the "Science" category, maybe "Idle".
You're a moron.
If you read both blogs you'd understand why Kurzweil doesn't know what he is talking about.
Here's the crux of his argument:
"We cannot derive the brain from the protein sequences underlying it; the sequences are insufficient, as well, because the nature of their expression is dependent on the environment and the history of a few hundred billion cells, each plugging along interdependently. "
Kurzweil just ignores this.
Kurzweil ridiculously optimistic, Myers ridiculously cynical?
I listen to both RIAA and non-RIAA stuff if I like the music, tangential business/politics nonwithstanding.
Our progress towards "reverse engineering" the brain may actually be SLOWING DOWN, not accelerating. Despite the wishes and dreams of computer scientists, animal rights adv. and folks like Kurzweil, the real nitty gritty of "figuring out the brain" comes primarily from painstaking experiments in the anatomy and physiology of the brain. The primary funder of this research in the US is the NIH. And funding has been stagnant if not decreasing in real dollars. Consequently, fewer smart students are entering the field and fewer labs are conducting the necessary studies. So even if the difficulty stays the same as we go deeper and deeper into the problem, our progress is only barely maintaining its current rate. But it is likely that the difficulty will (and has been) increasing, which means that the same or fewer labs, the same or less research $$$, our progress will DECELERATE, not ramp up... The rapid advances in computing only help a little in these studies...
If we want to figure out the brain, we must re-invest in science education AND increase funding for basic neuroscience research.
Maybe if Slashdot Editors weren't trolling around the internet LOOKING for just such scathing material, we wouldn't have this problem. It's turning into DIGG, in a bad way. I hate seeing articles titled "Bill gates kills 1,000,000 cute puppies"! only to have the actual article be about some random 10 year old workstation that blue-screened at a stuffed animal factory. I find that CMDTaco is usually the one with the most Torch-and-Pitchfork attitude in writing, usually trying to paint something in a bad light. My impression of him, is that if Ghandi was discovered to have used a Sony product, we'd see an article the next day "Ghandi supported evil capitalist empire" (Regardless of how Evil Sony is, the articles always seemed to have a slant to them)
Kurzweil is absolutely correct. His best argument is not the complexity of the genome, but focusing on the actual functional structures in the brain. A cortex composed of a billion repeating units is something we CAN feasibly simulate. Already, we have massive systems that run an algorithm spread across billions of separate instances. (google.com is one)
An "algorithm" could also model the behavior of a few neurons working in circuit.
Also, keep in mind that most of the complexity of the brain and body are completely unrelated to the task of thinking. Much of that genome codes for molecular machine parts needed to maintain and grow the hardware. There's all kind of defense and circulatory and support systems that we won't have to worry about when designing artificial minds.
And finally, when you consider the changes made to the brain from the enviroment : that doesn't make the problem harder. Once you have a self organizing neural system that works like the human brain but a million times faster, you expose that system to our environment and train it up just like we do with humans. Sure, it might take a few years for such a system to reach super-intelligence, but if your fundamental design was right then this would eventually happen.
is right. Myers criticism may be off the mark but Kurzweil's speculation about brain design, like some much of his other speculation, is bullshit. His basic argument in the blog post is that the amount of information in the human genome constrains the amount of information (and the complexity) required to design the brain. This thesis is wrong on a bunch of levels but let's take the most obvious. The amount of information in the genome is the amount of information that the "body" (to simplify) requires to replicate or create parts of itself. The amount of information required is relative to the machinery which is going to interpret it. There is no reason to believe we are dealing with a Turing machine here where the amount of bits required for a program to perform a function is going to be more or less consistent across languages and platforms (assuming similar complexity of the code). The machine interpreting the bits matters. So while the body may only need "50 million bytes" to create itself we may need many, many more millions of bits to specify how to build it. Just consider the complexity of protein folding.
Exactly so. The genome information assumption is absurd and arbitrary. It's like assuming that because I can buy a book an Amazon by transferring 1500 bytes of information to Amazon's website I can thus recreate that book inside a simulation using only 1500 bytes of code. In both this case and the issue of brain complexity, the mechanism for transforming the initial information into the finished product is far more complex than the "input data."
"I zero-index my hamsters" - Willtor (147206)
Kurzwell DID say it could be stored in a compressed format based on the size of DNA. That is still bullshit.
The question we are trying to address is: what is the complexity of this system (that we call the brain) [...]? The original source of that design is the genome (plus a small amount of information from the epigenetic machinery), so we can gain an estimate of the amount of information in this way.
Didn't PZ Myers say first that, on the contrary, DNA is merely giving a hint as to what the result of the "ontegeny" will be? That the real work is done by stochastic processes during development and therefore DNA doesn't tell us much at all about the final product? In which case, how can Kurzweil reduce the complexity of the brain to a what is only starter data?
Woo-woo aside, consciousness is almost certainly no more than "computing beyond our comprehension."
I say this because computing is the process of acting on data, using other data and procedures as the basis for action.
We know that computing does occur in the mind, we can perceive it at some levels. We also know that computing is an enormously successful strategy for coping with problems. This is so well understood and integral to the idea, that almost every problem we have that remains unsolved is expected to be at least partly solved by the application of computing. We know of no other process that yields results at the levels computing does. The number of problems we could *not* solve without unaided grey matter that have fallen to one or another computing strategies is huge, and that's understating the case.
We -- as a group, speaking generally -- have a very strong tendency to describe things we don't (yet) understand in terms of wonder; the analogy of the "unclimbable mountain" appears over and over. Realms we cannot see. Information we cannot have. Insights we cannot make. These are (at best) philosophical positions, because while they make these postulations with an air of great certainty, experience has shown that they simply are too limited in vision.
We couldn't fly; well, we do. We'll never make a good chess-playing program. Done. We'll never be able to make a biped robot walk. We could and did (and with a z-80!) Neural nets couldn't be effectively extended (MIT's Minsky, no less.) Wrong, they can and it is enormously enabling to do so. The director of the patent office once famously said that "Everything that can be invented has been invented." That was in 1899. I think its safe to say we've invented some things since then, even fundamental things. I could go on - for a long, long time, but the point should already be made: We're really, really bad at looking at where we are, and taking stances that such-and-such is impossible, not coming in X time, or "out of our realm(s.)"
Nowhere in nature have we encountered any process that incorporates anything even remotely like the idea of "spirit"; there is no neural operation, capacity or feature that we have discovered that does not slot neatly into some permutation of biologically engendered [electrical, chemical, mechanical.] We have found some other basic building blocks in brains that we think may be active participants in brain operations, but again, there is nothing known about them that isn't mundane. Nor is there anything else living in the world that we have discovered that is not constructed so.
While it would be interesting to make such a discovery, the existence of "I don't understand it" actually doesn't, historically speaking, imply that such a thing exists. What it has meant - every time so far - is that the pundit making the statement simply was unable to imagine the problem space well enough to visualize that a solution could exist. If you want to look clearly at what possibilities the future offers us, you have to get past the idea that because you can't visualize it as solvable within the realms of the mundane, it cannot be. That's been so dependably wrong as to be more a subject of humor than anything else. Not that it stops philosophers from declaring "consciousness is magic" in one baseless rationalization after another.
Sometimes it's a matter of the problem space. I well remember one fellow saying that we'd never be able to mimic human arm motions, because these were such complex motions, mathematically speaking, that they simply could not be "solved" in the time it takes us to do them. Today, we have fuzzy logic solutions that solve that problem (and many others) at a level far above just "doing math" operates, and yet, in an enormously simple manner; and you guessed it, the resulting motions are as flexible and hu
I've fallen off your lawn, and I can't get up.
Myers primary complaint was that Kurzweil used the number of genes in the genome and how many bits would be required to store that data as a predictor of how long it will take to completely understand the complexity of the human mind. Myers' post lays out a glimpse of the additional complexity involved and rightly points out the fallacy of making such a grand prediction based on such a small amount of information and understanding. Of course Kurzweil's entire career and fame are now dependent on people continuing to fall for his dramatic generalizations and overreaching predictions that "Something Big" is right around the corner. I have watched Kurzweil talk and sometimes it seems as if he has a messianic complex.
He should go back to what he does well - inventing interesting and useful machines. His prickliness displayed towards those who disagree (often with good reason) with his worldview has done more to harm his reputation than any of his critics' corrections. If you can't take criticism, you shouldn't be a futurist. He also won't be the first whose hubris will lay him low. Get back to the lab while you still can, Ray...
That is all.
I can see it now...
60% side with PZ Myers
30% side with Ray Kurzweil
10% side with CowboyNeal
The real problem here is that PZ and Ray both have very specific philosophical commitments that are in conflict. Just like PZ rails against critics of strict Darwinian evolution, (the idea that everything about life can ultimately be explained via the Darwinian mechanism), he struggles with people like Ray who see mind as a distinct entity from brain.
In both cases, Ray and PZ use science as a way to promote their philosophical biases and beliefs. Its not unlike the case where a young earth creationist cherry picks data to support his belief that the earth is 6000 years old, but ignores other evidence for an older earth.
It gets really ugly when the science goes out the door and the mud-slinging begins. PZ is famous for that. My recommendation is to call him on it and move on. There are far better scientists and far more ethical scientists out there than PZ.
Ray? I'm not so sour on Ray, except to note that he is more of a futurist and inventor than a scientist. Everything he says should have an asterisk next to it.
In other words because Kurzweil's theories are, in your opinion, nonsense they shouldn't be tested?
It all starts at 0
In other words because Kurzweil's theories are, in your opinion, nonsense they shouldn't be tested?
It's not my "opinion". It's based on theory, the very information theory that he criticizes Myers for not understanding. Obviously he doesn't understand it either.
In other words because Kurzweil's theories are, in your opinion, nonsense they shouldn't be tested?
It's not my "opinion". It's based on theory, the very information theory that he criticizes Myers for not understanding. Obviously he doesn't understand it either.
If you mean the bit about the brain being a Turing machine, then I would say its fine to try testing that theory (many people have been for many years), but the assumption that consciousness is substrate-independent is completely unjustified.
Sceptics are adept at making really quite fetching mincemeat sculptures of religion, alternative medicine and the new age, but we need some serious attention paid to the transhumanist/singularist/cryonicist belief cluster. Because these are smart people, they are likely our friends, they share a lot of our notions and they are proving that the main use apes with delusions of grandeur like ourselves put intelligence to is being stupid with far greater efficiency.
Obligatory RationalWiki plug: Cryonics. I was actually neutral-to-positive on the subject until a friend started looking seriously into spending $120k on freezing his head and I started looking seriously into what he was getting into. And goddamn, it's woo all the way down. Woo by people who are ridiculously smarter than you or me and use it to be dumb. How do you fight that sort of woo? Piece by piece, of course. So I have to learn the bollocks on its own terms to take it down (at which point you see goalpost-moving, reversal of burden of proof, etc., all the things apes with delusions of grandeur do so well). And it's just AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA.
tl;dr: Singularitarians talk as much utter bollocks as creationists, climate change deniers, New Age hippies and the tobacco industry. There needs to be more analysis and dissection of said bollocks.
http://rocknerd.co.uk
But then he goes right on to emphasize that "the genome constrains the amount of information in the brain prior to the brain's interaction with its environment."
To be sure, the genome must be a major factor. I recognize that human bodies are not the products of genomes alone -- indeed, over 90% of the cells in our bodies (counting by sheer number) don't even have our DNA because they belong to our symbiont species -- but surely the complexity of the blueprint for brain-developing-systems goes a long way towards approximating total complexity of the developed-brain-system. Part of my intuition here is an anticipated relative complexity between environment and the machinery of the brain itself. The brain seems to be a damned complex thing, just in its construction.
Still, your point is important. Our genetic code only really works in its environment. Some stimulation can be piped in from real world sensors, other stimulation can be simulated. But that's only negligible for the simpler stuff, which might arguably be the things during the post-birth development that occur to us offhand, our prominent sensory experiences. The complexity of the interplay between our developing bodies and our nutrients and myriad symbionts (indeed, even the creatures we might mistakenly think of as parasites which could in fact be helping keep our immune systems tuned properly for example) is no trivial matter.
"The brains we'd been simulating growing didn't quite work until we added, to our chagrin, the entire body. And even then we had to add in most of the symbiotic species to avoid Autism, Alzheimer's, Crohn's disease, and lupus. But that was only 30% additional complexity... um, once we figured out what all the symbiotic relationships were. Ahem. The good news is that we cured half those diseases and lifted medical science to the verge of curing the rest! The bad news is that we lagged behind the symbolic AI developers by 20 years in creating something that wasn't retarded. But we like our results better. And we're the ones paving the way to Upload. :P"
As someone who actually does neuroscience research, the tools and techniques available today were almost undreamed of a couple of decades ago. Nothing is slowing down. But more money is always greatly appreciated, of course.
Why would we even want to simulate a human mind? To spare ourselves trouble of thinking? While we're at it, why don't we build a bunch of sex robots to save us the trouble of having sex. Then I guess we'll sit in front of the TV for the rest of eternity. Sounds like a blast.
A Turing machine is equivalent, from a theoretical point of view, to any computer.
The brain is physical thing, so it can be simulated, by a Turing machine or any powerful enough computer.
He points out that there are comparatively few genes. That's nice. Any undergraduate in biology knows this argument and it's been around for decades.
Kurzweil seems to have made a career out of taking other people's ideas, stating the obvious, and getting his name associated with it. People should really stop listening to him.
There is no reason to believe we are dealing with a Turing machine here ...
And here is where you fail to understand the argument: there is ALL THE REASON to believe we are dealing with a Turing machine here, because a Turing machine is able to compute EVERYTHING that is computable, regardless of complexity, and evidently the process of building a (human) brain is computable since in fact it has been "computed" a few billion times. (On the other hand, figuring out if some arithmetic statements are true or not is not a computable problem, see e.g., Godel's theorem). So whatever is interpreting genome-language instructions to build a brain is doubtlessly a Turing machine.
And however, our task is *much simpler* than that, since although the genome-language Turing machine has indeed to "know" things as complex as protein folding to be able to do its job, we can *completely* abstract that and similar problems: our models of the brain can be happily built with concepts such as "information", "processing", "perception data", "behavior", etc., which are much higher level (and therefore much more concise) than raw molecular biology.
So the argument is this: the construction of a brain is computable (has been computed), and we have a model of computation that starts with the genome (i.e., a very definite amount of information) and ends with a functioning brain (which is what we want), so we know the task is *possible* and the complexity manageable *in principle*. BUT ... we won't go at it the same way the genome does, at least not for information-processing purposes which is one of our immediate interests, we'll take a few shortcuts to make the complexity even more manageable than "in principle". Sure, the project might succeed or not, but that's an *empirical* question to be decided by facts (and hopefully, constructively, i.e., trying to build one and either succeeding or failing in a way that we can analyze and use to attain a higher level of understanding). However objections that try to prove that the project is intrinsically (i.e., theoretically) non-viable need to be carefully examined, and if they are based in the non-Turing-machin-ness of the phenomena under observation then they need to be clearly rejected and showed wrong.
When the dust settles, none of these terms will matter. In the process of better understanding the human mind, all these vague sentiments will be unpacked into different conceptual primitives. It'll be like quantum mechanics. Anyone who says they are completely comfortable with the unpacking will be someone who doesn't fully understand it.
I think you are making too big a deal of an artificial mind achieving a kindred consciousness. I think we have as much or more to learn about what we aren't (other forms of mentation) as what we are. To a primitive man, a mirror is an interesting discovery, but how much do you really learn pointing it back at yourself? We'll find ourselves in an uncomfortable exchange with these highly non-human mentalities. Someone will come along and add a fatuous ego module, and suddenly the exchange will be less uncomfortable. It'll be Joseph Weizenbaum all over again. Deep rapport will turn out to consist of Elizaesque gimmicks.
I tend to regard consciousness as more of a sentient sentiment than something amenable to rational definition. Perhaps consciousness is just a toxic overdose of self-sentiment. Toxic in the sense that it overflows into the belief system.
There is no reason to believe we are dealing with a Turing machine here ...
And here is where you fail to understand the argument: there is ALL THE REASON to believe we are dealing with a Turing machine here, because a Turing machine is able to compute EVERYTHING that is computable, regardless of complexity, and evidently the process of building a (human) brain is computable since in fact it has been "computed" a few billion times. (On the other hand, figuring out if some arithmetic statements are true or not is not a computable problem, see e.g., Godel's theorem). So whatever is interpreting genome-language instructions to build a brain is doubtlessly a Turing machine.
And however, our task is *much simpler* than that, since although the genome-language Turing machine has indeed to "know" things as complex as protein folding to be able to do its job, we can *completely* abstract that and similar problems: our models of the brain can be happily built with concepts such as "information", "processing", "perception data", "behavior", etc., which are much higher level (and therefore much more concise) than raw molecular biology.
So the argument is this: the construction of a brain is computable (has been computed), and we have a model of computation that starts with the genome (i.e., a very definite amount of information) and ends with a functioning brain (which is what we want), so we know the task is *possible* and the complexity manageable *in principle*. BUT ... we won't go at it the same way the genome does, at least not for information-processing purposes which is one of our immediate interests, we'll take a few shortcuts to make the complexity even more manageable than "in principle". Sure, the project might succeed or not, but that's an *empirical* question to be decided by facts (and hopefully, constructively, i.e., trying to build one and either succeeding or failing in a way that we can analyze and use to attain a higher level of understanding). However objections that try to prove that the project is intrinsically (i.e., theoretically) non-viable need to be carefully examined, and if they are based in the non-Turing-machin-ness of the phenomena under observation then they need to be clearly rejected and showed wrong.
You are begging the question. You are essentially saying that genome is computable because it is computable. Here's your task: show me how the cellular processes involved in cell replication and specialization operate like a Turing machine. Obviously this does not mean that these process could not be simulated using a Turing machine, but, the argument is that these processes operate like a Turing a machine and thus we have a good idea of what "50 million bytes" means by an analogy to computer programming.
In any case even if the genome is computed, which may or may not be the case, the fact that there are "50 million bytes" by itself tells us nothing about how much information we need to understand how to design the brain. It tells us the *lower* bound of what the body needs to "know" to build the body, not the *upper* bound of what we need to know to build a brain. The problem here is the distinction between syntax and semantics. The body only needs the syntactical information to work but we need the semantic "information" to understand *how* it works. Also consider that the development of the body and brain are a process in which the syntax may have different meaning at different points in the process of development (and there is evidence that this is the case) which would further increase complexity. His thesis is predicated on an incredibly naive and simplistic understanding of biology which for me makes all of his pronouncements suspect because he is not taking into account such complexity. He's a charlatan, plain and simple.
Suppose this machine can be created. Another issue we must ask as scientists is, how will we know we were successful? What are our criteria? As far as I know, there is no test that can prove another man conscious. We assume it. So, as a scientist, I insist that no machine can be produced with consciousness, and nobody may prove me wrong. Mulling the issue, I conclude that the question itself is nonsense. Turing thought the same as me, and this is why the Turing test exists - it is his attempt to reframe the question in other terms, terms that are verifiable. And I can accept those terms or reject them - they are not fundamental, arising from the nature of consciousness itself. What I cannot accept are pseudoscientific ramblings on the pros and cons and "emergent properties of consciousness," which, to me, sound whiny. Biology is complex. But that, in itself, is not the reason why consciousness is a difficult problem.
A Turing machine is equivalent, from a theoretical point of view, to any computer.
The brain is physical thing, so it can be simulated, by a Turing machine or any powerful enough computer.
Your reductionism is not only logically flawed but empirically false. Your argument is the following: all physical things can be simulated by a Turing machine; the brain is a physical thing; therefore a Turing machine can simulate a brain. Do you see the problem here? Let me help. It's the major premise. Not all physical things can be simulated by a Turing machine. It's not even clear that all physical things can be simulated regardless of the method because of the inherent randomness of physical events. In case you don't see the connection, let me spell it out. Simulation requires abstraction and you can't abstract from random events because by definition there is no rule for the abstraction.
There is no reason to believe we are dealing with a Turing machine here ...
And here is where you fail to understand the argument: there is ALL THE REASON to believe we are dealing with a Turing machine here, because a Turing machine is able to compute EVERYTHING that is computable, regardless of complexity...
Also, while I don't need this point for my argument you should know that your assertion that the Turing machine can compute anything computable is a conjecture called the Church-Turing thesis. It's not proven but of course it seems like a fairly solid thesis. However what is objectionable in your proposition is that you are reducing computability to Turing-computability. While the point is subtle think of it like this: anything Turing-computable is computable but anything computable is not necessarily Turing-computable.
Given your over-estimation of the domain of Turing-computability I'm pretty skeptical of your completely unsubstantiated thesis that the brain must be a Turing machine. It's simply dogma. Your prejudice is not uncommon and not surprising. In fact it's probably the most common prejudice amongst those educated enough to know what a Turing machine is but not quite educated enough to know its limits. So you are out of your depth but in good (or at least numerous) company.
viewed from a couple of decades, sure, and yes the advancement in techniques is impressive, but viewed from the past 5 years and, worse, the projection for the next 5 years, the outlook for even maintaining progress and its required funding is pretty bleak.
and looking at the quality and skill set of American students entering neuroscience graduate school, also very depressing -- the RISE is in students coming from overseas, particularly China... US students also don't want to do the required hard work needed to do serious systems-level neurophysiology.
The Chinese investment in the neurosciences is similarly impressive. Given the current trends, the US *will* be overtaken within a couple of decades... so I beg to differ... I see current trends within the past 5 years in the US as a slowing down of progress in systems-level neuroscience...
The progress that has been made in the last five years is similarly incredible.
"American students"
Ah... you have an American bias. Yeah, could be American neuroscience, done by Americans, is in trouble. I don't know. I'm not an American.
That seems to be common problem here. Fortunately for research in many areas, we are not all that is out there.