Just to prove that I can read books faster than the three months the English history took me, I've just finished Doug Hofstadter's I am a Strange Loop. It's hard to live up to having your first book win a Pulitzer, and this is no GEB. Yet, at the same time, there are many similarities, not least because Hofstadter considers Loop to be a retelling of the central story of GEB... how mind can appear from physically interacting particles. (Though I would say his best stab at answering that question comes from his dialogue "Who shoves whom around in the careenium?" which appeared in Metamagical Themas - indeed, the careenium forms a central analogy in the current book.)
Essentially, the book presents Hofstadter's ideas on what a mind is - namely, a strange loop. Since that noun phrase may not excite much recognition, the book helps to explain and expand on the idea using a host of analogies and explanations. We all understand what a feedback loop is, a microphone/speaker system produces something that it itself detects (or observes) and channels it back through the system again. A strange loop is similar, but with an attached set of symbols that react to these observations and change in response to them.
One might object that matter can't mean anything, so how can it be a symbol? Here again, the analogy with Gödel's mathematical tricks is useful. Gödel demonstrated that an integer, subject to appropriate patterning, can bear a meaning. Gödel pushed things even further by showing that such an integer can even be forced to observe itself and its meaning can be about itself. If a numerical pattern can mean something, surely a material pattern can mean something.
I'll borrow my own analogy from the Principia Discordia:
When I was 8 or 9 years old, I acquired
a split beaver magazine. You can imagine
my disappointment when, upon examination
of the photos with a microscope, I found
that all I could see was dots.
Now, clearly it's the pattern of the dots that makes the split beaver. Is the pattern made of matter? Well, if there were no paper and no ink, there could be no beaver. But is that line, or that curve, or that pinkness made of matter? The alternative seems very obnoxious... that there is magical non-material pattern-stuff, out of which the pattern is made. So I take the third alternative, that the pattern is not made of anything. It is a pattern, an arrangement, a scheme. The pattern uses matter as its substrate, but the pattern itself is... a pattern.
Borrowing one of Hofstadter's analogies, consider the rainbow. Is a rainbow made of matter? Surely, if there were no waterdroplets, there would be no rainbow. But if you were standing next to to the water droplets that were casting rainbow light into someone else's eyes, there would be no rainbow there. A rainbow is (pace Heimdall) not a bridge on which one can walk.
To be sure, a rainbow or a split beaver picture is not conscious of itself, but human brains, with rare exceptions - Denise Richards' comes to mind - are more complicated than a beaver picture, and have the sensory apparatus to close the strange loop and observe their own patterns.
So can patterns of neuronal firing have meaning and be the seat of consciousness? Certainly the brain is just made out of meat. But patterns are not made of meat, they are just patterns, and they can hold meaning.
Light impinging on the eyes of a monkey gets converted into a signal that travels to the optics centers of the brain where various filters act upon the message and gets kicked around to other parts of the brain that light up when they recognize a pattern of signals that corresponds to a banana. Other patterns in the brain are coincidentally reacting to the signals traveling from the stomach regarding its emptiness. These patterns interact in a way that excites the motor part of the brain to take action to grab the real banana. Is the banana pattern the same as seeing a banana? Is the pattern started by the stomach the same as the experience of hunger. Sure that latter pattern (a skeptic might say) may coincide with a state of hunger, but surely there's no hungriness there. How can meat be hungry? How can a pattern residing in meat be hungry?
If that pattern leads to changes in objective behavior that result in the monkey seeking out and consuming a banana, it surely coincides with and plays the role of hunger. Maybe it is hunger after all! The typical alternative, some form of dualism, seems a worse explanation - at best it's an unnecessary multiplication of entities, at worst it's nonsense.
People sometimes talk about the idea of a "grandmother neuron": a neuron that fires when you see your grandmother, presumably creating the experience of recognizing one's grandmother. While this is somewhat naive and generally an object of ridicule, something like this seems to actually be the case. When brains are stimulated, unusual experiences are evoked: "It seemed to me as if I was seeing children dancing and that I was carrying my dance shoes in my hands.”
Surely that patient was conscious of this faux experience. Was an electrical discharge somehow upsetting her immaterial soul? Or was it addling the meat of her brain? Or was it diddling the patterns in the brain? I think the last is the closest to the truth of the substrate of consciousness. Certainly it was messing with the meat, but the experience she was experiencing was due to the perturbation of the pattern.
Clearly there are lots and lots of patterns in a brain simultaneously. As I hopped out of the shower this morning, I was humming a snippet of Wagner, feeling the cool sensation of air on my wet skin and thinking about writing this monster blog entry and, in particular, this very sentence. I find myself wondering if the human instinct and neural machinery for language contributes to the illusion that there is an indivisible "I" that lords it over the body from its soular plane. Although I can be conscious of several different sorts of stimuli, I find that I can only have a single internal monologue. I can't hear myself thinking two different 'verbal' thoughts. In fact, I can only imperfectly get my internal iPod to play well-known music while also carrying out 'verbal' thoughts. Maybe this is a result of the linearity of speech and the inadequacy of the verbal chunks of the brain to handle more than one 'train of thought' at a time. And this contributes to the idea of a one individual "I" that runs the body. If there is a single train of verbalization, it obviously has one speaker. And that speaker is "I".
I'm sure we've all had the experience of driving down the street along a familiar path and then suddenly thinking to oneself, "Whoa! Where have I been for the past fifteen minutes? I don't remember anything. I was, like, totally on autopilot!" Of course, you were right there, driving the damn car with (presumably) as much skill as usual. You didn't need the verbal part of the brain to drive the car, so it powered itself down for a bit. Then some random stimulus poked at it, and it got back to work. Maybe we've identified too strongly with that verbal talker part of the brain as what the "I" is. You (inasmuch as you are anything) are all of those things, the driver, the cool-feeler, the Wagner-hummer, the talker, the rememberer, etc. All of these things are just a few of the simultaneous patterns bouncing around inside your brain.
Okay, let me spiral back to Hofstadter and his loops. He spends rather a lot of time in the middle section discussing the idea that we also exist in other people's heads. As imperfect copies obviously, but just as one represents oneself internally, one must represent the others that one deals with. And the closer you know someone, the more fidelity your mini-loop has to the original. In some ways I'm amenable to what he's saying, and it is the only sort of immortality I have to look forward to, but his grander claims are not quite convincing. It feels like kicking a man when he's down, but these sections are also intricately tied to the death of his wife. I believe him when he says his ideas are not merely "the passionate ravings of a suffering individual who had expediently modified his belief system in order to give balm to his grief." Nonetheless, I don't think these are the strongest chapters of the book.
On the other hand, the later chapters are some of the best, where he provides a summation of all his foregoing ideas and a useful critique of other alternatives. He dispenses with zombies and the inverted spectrum almost too rapidly, as though they're hardly worth his time, which (possibly) they aren't.
One last analogy to ponder (originally due (as I read from a footnote) to Bill Frucht) is that consciousness is not a power moon-roof. Consciousness is not an optional feature that needs to be acquired in addition to the complexity inherent in a strange loop. It's as if, says Hofstadter, one were to buy a car with 12 cylinders and 450 horsepower and then ask... "How much more would I have to pay in order to get Racecar Power (TM)" Racecar power is not an option, it comes with the territory once you've got enough horsepower under the hood. Similarly, once brains and their patterns get complex enough, one gets consciousness "for free".