Friday, March 01, 2013

I wonder why I wonder why

Chris Adami joins the blogosphere! Let's hope the long post linked to below is a harbinger of more to come. Chris started in theoretical physics but has since migrated into areas like artificial life, evolution and neuroscience. See also Brain, Mind, Evolution.
Your conscious you: ... After all this mathematics is done, we are left with a number that Tononi calls "Phi" (also the title of his most recent book), which characterize the capacity of any computing machinery to integrate information. What does this construction do for you? Right now, nothing of course. But imagine Tononi could record the activity patterns of your brain as you read this... shall we call it a blog? Phi could tell you if you are dreaming or in dreamless sleep, because your brain integrates information only during dreaming sleep. In the dreamless sort, you are unconscious, you have no experience at all. And as it so happens, Tononi is in a position to make precisely these types of measurements, as the director of a sleep laboratory. But this is not where the usefulness of Phi ends. If Phi can measure whether or not you are conscious, then shouldn't it be able to determine whether people in a comatose state are in a vegetative state without any consciousness at all, or else in a so-called locked-in state, fully conscious but unable to communicate this state to the outside world (think "The Diving Bell and the Butterfly")? There is now some evidence that Phi can distinguish between vegetative and conscious states but definitive proof will only be available when we can record from brains in more sophisticated ways than we can do today.

"Fine" you say, "I grant you that there may be a way to measure whether a computing machine integrates, or just reproduces, information". "Unless I'm caught in a coma, why should I care?"

And I tell you in return: "You have forgotten the first half of this blog post haven't you, where I insisted that evolution--the process that knows not what it designs--can do things that people can't do." Yes, that's right: evolution can create computational systems that integrate information at high levels, because evolution is not concerned with beautiful, predictable design. Evolution is messy, opportunistic, and unpredictable. Evolution takes what works and runs with it, whether it is neat or not, whether it adheres to design standard ISO9000 or not. More importantly, evolution creates designs that wastes as little as possible, reusing the same components over and over, and doing all these things at the same time. As a result, evolved computing systems integrate information. At a massive scale.

So, what makes natural computing machines such as brains interesting is information integration, and from what we know today, this level of integration cannot be achieved by design. What should we learn from this? Well, I think you beat me to it, this time. We should use evolution as the process that leads us toward the undesignable, toward the computer that integrates (for reasons of expediency only) to such an extent that the objects it perceives don't just evoke a reaction, they evoke an experience. There is a good reason we should expect experiences to be selected for: they allow the recipient of the experience to make better predictions about the future, and further the survival of the species that has these experiences.

I wonder why I wonder why. I wonder why I wonder. I wonder why I wonder why I wonder why I wonder! —Richard Feynman

1 comment:

ben_g said...

Still doesn't explain why there needs to be such a thing as "experience", only why there needs to be a log of salient data. I'm not sure we'll ever know why such a thing as experience exists.

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