Myers still thinks Kurzweil does not understand the brain

The blog war between PZ Myers and Ray Kurzweil continues. Myers has now retorted to Kurzweil's retort:

...you can't measure the number of transistors in an Intel CPU and then announce, "A-ha! We now understand what a small amount of information is actually required to create all those operating systems and computer games and Microsoft Word, and it is much, much smaller than everyone is assuming." Put it in those terms, and the Kurzweil fanboys would laugh at him; put it in terms of something they don't understand at all, like the development and function of the brain, and they're willing to go along with the pretense that the genome tells us that the whole organism is simpler than they thought.

I presume they understand that if you program a perfect Intel emulator, you don't suddenly get Halo: Reach for free, as an emergent property of the system. You can buy the code and add it to the system, sure, but in this case, we can't run down to GameStop and buy a DVD with the human OS in it and install it on our artificial brain. You're going to have to do the hard work of figuring out how that works and reverse engineering it, as well. And understanding how the processor works is necessary to do that, but not sufficient.

Myers concludes,

In short, here's Kurzweil's claim: the brain is simpler than we think, and thanks to the accelerating rate of technological change, we will understand it's basic principles of operation completely within a few decades. My counterargument, which he hasn't addressed at all, is that 1) his argument for that simplicity is deeply flawed and irrelevant, 2) he has made no quantifiable argument about how much we know about the brain right now, and I argue that we've only scratched the surface in the last several decades of research, 3) "exponential" is not a magic word that solves all problems (if I put a penny in the bank today, it does not mean I will have a million dollars in my retirement fund in 20 years), and 4) Kurzweil has provided no explanation for how we'll be 'reverse engineering' the human brain. He's now at least clearly stating that decoding the genome does not generate the necessary information — it's just an argument that the brain isn't as complex as we thought, which I've already said is bogus — but left dangling is the question of methodology. I suggest that we need to have a combined strategy of digging into the brain from the perspectives of physiology, molecular biology, genetics, and development, and in all of those fields I see a long hard slog ahead. I also don't see that noisemakers like Kurzweil, who know nothing of those fields, will be making any contribution at all.

Link.

Kurzweil responds to PZ Myers

Ray Kurzweil has retorted to PZ Myers's claim that he does not understand the brain:

For starters, 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.

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. 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.

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.

Be sure to read the entire response.

Myers: Kurzweil is a "pseudo-scientific dingbat" who "does not understand" the brain

Biologist and skeptic PZ Myers has ripped into Ray Kurzweil for his recent claim that the human brain will be completely modeled by 2020 (Note: Not that it's particularly important, but Kurzweil did say it'll take two decades at the recent Singularity Summit, not one). In a rather sweeping and insulting article titled, "Ray Kurzweil does not understand the brain," Myers takes the position that the genome cannot possibly serve as an effective blueprint in our efforts to reverse engineer the human brain.

In regards to he claim that the design of the brain is in the genome, he writes,

Kurzweil knows nothing about how the brain works. It's [sic] design is not encoded in the genome: what's in the genome is a collection of molecular tools wrapped up in bits of conditional logic, the regulatory part of the genome, that makes cells responsive to interactions with a complex environment. The brain unfolds during development, by means of essential cell:cell interactions, of which we understand only a tiny fraction. The end result is a brain that is much, much more than simply the sum of the nucleotides that encode a few thousand proteins. He has to simulate all of development from his codebase in order to generate a brain simulator, and he isn't even aware of the magnitude of that problem.

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. We haven't even solved the sequence-to-protein-folding problem, which is an essential first step to executing Kurzweil's clueless algorithm. And we have absolutely no way to calculate in principle all the possible interactions and functions of a single protein with the tens of thousands of other proteins in the cell!

Myers continues:

To simplify it so a computer science guy can get it, Kurzweil has everything completely wrong. The genome is not the program; it's the data. The program is the ontogeny of the organism, which is an emergent property of interactions between the regulatory components of the genome and the environment, which uses that data to build species-specific properties of the organism. He doesn't even comprehend the nature of the problem, and here he is pontificating on magic solutions completely free of facts and reason.

Okay, while I agree that Kurzweil's timeline is ridiculously optimistic (I'm thinking we'll achieve a modeled human brain sometime between 2075 and 2100), Myers's claim that Kurzweil "knows nothing" about the brain is as incorrect as it is disingenuous. Say what you will about Kurzweil, but the man does his homework. While I wouldn't make the claim that he does seminal work in the neurosciences, I will say that his efforts at describing the brain along computationally functionalist terms is important. The way he has described the brain's redundancy and massively repeating arrays is as fascinating as it is revealing.

Moreover, Myers's claim that the human genome cannot inform our efforts at reverse engineering the brain is equally unfair and ridiculous. While I agree that the genome is not the brain, it undeniably contains the information required to construct a brain from scratch. This is irrefutable and Myers can stamp his feet in protest all he wants. We may be unable to properly read this data as yet, or even execute the exact programming required to set the process in motion, but that doesn't mean the problem is intractable. It's still early days. In addition, we have an existing model, the brain, to constantly juxtapose against the data embedded in our DNA (e.g. cognitive mapping).

Again, it just seems excruciatingly intuitive and obvious to think that our best efforts at emulating an entire brain will be informed to a considerable extent by pre-existing data, namely our own DNA and its millions upon millions of years of evolutionary success.

Oh, and Myers: Let's lose the ad hominem.