Sunday, August 22, 2010

Beyond Kurzweil and Myers: A Useful Brain Emulation Viewpoint

George Dvorsky provides a measured and reasonable approach to the question of machines emulating the human brain in this well written article on "making brains". While quite short and lightly documented, Dvorsky's piece provides a useful outline of the problem, and a fairly sound description of a good approach for attacking the problem.
While I believe that reverse engineering the human brain is the right approach, I admit that it's not going to be easy. Nor is it going to be quick. This will be a multi-disciplinary endeavor that will require decades of data collection and the use of technologies that don't exist yet. And importantly, success won't come about all at once. This will be an incremental process in which individual developments will provide the foundation for overcoming the next conceptual hurdle.

But we have to start somewhere, and we have to start with a plan...The idea of reverse engineering the human brain makes sense to me. Unlike the rules-based approach, WBE works off a tried-and-true working model; we're not having to re-invent the wheel. Natural selection, through excruciatingly tedious trial-and-error, was able to create the human brain—and all without a preconceived design. There's no reason to believe that we can't figure out how this was done; if the brain could come about through autonomous processes, then it can most certainly come about through the diligent work of intelligent researchers.

...A number of critics point out that we'll never emulate a human brain on account of the chaos and complexity inherent in such a system. On this point I'll disagree. As Bostrom and Sandberg have pointed out, we will not need to understand the whole system in order to emulate it. What's required is a functional understanding of all necessary low-level information about the brain and knowledge of the local update rules that change brain states from moment to moment. What is meant by low-level at this point is an open question, but it likely won't involve a molecule-by-molecule understanding of cognition. _SentientDevelopments
Dvorsky goes on to describe the type of multi-disciplinary approach he has in mind, and bravely makes a prediction as to how long the effort will likely take: 50 to 75 years. This is a much longer timespan than Kurzweil and most AI researchers are giving, but I suspect it is closer to a realistic mark.

There are a couple of small criticisms I have to make. Dvorsky expects a workable brain emulation to be built within a "digital substrate":
.... if you believe that there's something inherently physical about intelligence that can't be translated into the digital realm, you've got your work cut out for you to explain what that is exactly—keeping in mind that any informational process is computational, including those brought about by chemical reactions. Moreover, intelligence, which is what we're after here, is something that's intrinsically non-physical to begin with.
Here, it seems that Dvorsky has it backwards. It is the persons who believe that intelligence can be made to work in a different physical substrate than the brain who bear the burden of proof to show that intelligence can be "transferred" to the "digital realm." We only have one proof of concept of intelligence up until now, which is a bloody ball of fat resting on a stalk rising between the shoulders of homo sapiens.

In another place Dvorsky asserts:
... the brain contains masterful arrays of redundancy; it's not as complicated as we currently think.
In truth, the brain is far more complicated than we can currently imagine. The question should be: Is the relevant functionality within the brain/mind which generates consciousness and intelligence, perhaps "not as complicated as we currently think?" Al Fin cognitive theorists believe that such a thing is possible, as long as we take care not to stumble amongst the numerous overlapping logical levels which present themselves whenever attempting to deal with this problem.

Dvorsky is quite right that the brain emulation problem is going to require extensive multi-disciplinary effort. We will need multi-disciplinary teams, as well as team members who themselves have multi-disciplinary training.

The great online debate between Ray Kurzweil and PZ Myers continues unabated, but it has very little to do with the eventual creation of a machine intelligence modeled after the brain.

If I had to choose one or the other to lead an effort to create an artificial brain, I would choose Kurzweil, hands down. Myers is an academic on the "intellectual" side -- an intellectual being someone who is rarely challenged by reality when he makes a mistake. Kurzweil's inventions and products have to work. That puts Kurzweil firmly in the reality-based camp, regardless of how many in the media and academia call him a kook.

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