Minds and Brains

This picture was drawn by Douglas Hofstadter for his classic dialogue “Prelude…Ant fugue” in his masterful Godel, Escher, and Bach. In the dialogue he asked a simple yet highly illuminating question: what does the picture say?

On the “top” level, it says “MU”, alluding to the Zen parable of Joshu and the dog. In this parable, a monk asks Joshu “does a dog have Buddha-nature?” Joshu, with immediate fervor, replies “MU!”. Translated, this statement basically means that Joshu denied the legitimacy of the question. He “unasked” the question. The relevance of the parable to the question of reductionism or holism is made clear when one attempts to answer the above question: what does the picture say? One cannot simply assert that it says “MU”, although on the top and bottom levels it says as much (You cannot see it in the above copy, but the individual letters are made out of tiny iterations of “mu”). That the picture says “MU” is trivially true, but it fails to capture the total meaning of the picture.

The beauty of Hofstadter’s diagram is only apparent after you let the meaning of the parable sink in. Do all questions have precise and definite answers? Can we really ask questions like “Should the brain be understand in terms of reductionism or holism?” and expect simple answers? Is it not wiser to instead “unask” such questions? Perhaps that question should be unasked as well!

I love this diagram on multiple levels, which is fitting I think, so I thought I would share it with you all. Please spend the time to ponder on the question of what the picture really says, and see if you come to the same conclusion as Joshu.

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I am a big fan of Douglas Hofstadter, the author of the classic Godel, Escher, Bach and more recently, I Am A Strange Loop. Hofstadter is a master of metaphors and today I would like discuss one metaphor in particular, The Careenium.

Hofstadter asks you to imagine a frictionless billiards table with lots and lots of tiny, magnetic marbles, or “simms”(small interacting magnetic marble), bouncing around, careening endlessly. Because these simms are slightly magnetic, they are apt to stick together into clusters called “simmballs”(see where this is going yet?). These simmballs are more or less stable with simms transferring in and out endlessly. Furthermore, imagine that the walls of the billiard table are sensitive to the outside environment and for every force, the walls flex inwardly slightly. Naturally, this flexibility is reflected in the careening simms and ultimately in the large simmballs.

Thus the simmballs be be said to encode for the events in the environment and in principle, if someone was well-versed in Careenium mechanics, they could interpret the simmballs as being symbolic. In case you haven’t figured out the mappings of the metaphor yet, let me lay it out explicitly. The simms map onto neurons(small events) and the simmballs map onto patterns of neurons(larger events) and by virtue of encoding for the environment, the simmballs(symbols) have representational qualities.

The point of Hofstadter’s metaphor is relatively simple. He wants you to imagine a scenario where the brain(Careenium) could be seen in two different perspectives. One perspective, which comes naturally to scientists, is reductionist. That is, one could in principle view all the activities of the Careenium in terms of the tiny simms bouncing around, acting in accordance with well-known laws of physics. On the other hand, one could take could the high-road, and view the system in terms of the larger simmballs and their macroscopic, representational properties.

In order to help you visualize the implications of the metaphor, Hofstadter asks you to imagine two perceptual shifts of the Careenium. The first shift is to speed everything up, so that the fast-moving simms become too fast to be seen by the naked eye and the larger, slower moving simmball clusters become more active, bouncing around in a lively fashion, interacting with each other. The second perceptual shift involves zooming out so that the the simmballs become the only thing one can attend to. With these two perceptual shifts in mind, Hofstadter asks the following question: who shoves whom around inside the Careenium?

On one hand, there is the view that the tiny, meaningless simms are the primary “shovers” and the simmballs are merely along for the ride. On the other perspective, zoomed out and sped up, the simmballs are the only interesting feature of the system, with a rich symbolic “logic” that corresponds to the environment being represented. Which perspective is the “truth”? Well, as Hofstadter says, it “all seems topsy-turvy.” I’ll leave you with a quote from the book:

From our higher-level macroscopic vantage point as we hover above the table, we can see ideas giving rise to other ideas, we can see one symbolic event reminding the system of another symbolic event, we can see elaborate patterns of simmballs coming together and forming even larger patterns that constitute analogies-in short, we can visually eavesdrop on the logic of a thinking mind taking place in the patterned dance of the simmballs. And in this latter view, it is the simmballs that shove each other about, at their own isolated symbolic level.

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Misreading the mind: If neuroscientists want to understand the mystery of consciousness, they’ll need new methods.

I thought this article was an interesting insight into the thought process of those who disregard the relevance of neuroscience for understanding the mind. The terminology Lehrer uses gives him away:

Even our sense of consciousness is explained away with references to some obscure property of the frontal cortex.
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[According to reductionism]The mind, in other words, is just a particular trick of matter, reducible to the callous laws of physics.
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You are simply an elaborate cognitive illusion, an “epiphenomenon” of the cortex. Our mystery is denied.

All of these quotes highlight a curiosity in Lehrer’s phrasing. Does he really think that if neuroscience succeeds in explaining cognitive phenomena in mechanistic terms, the mind will be “explained away”? Was heat “explained away” when we reduced it to the movement of molecules? Were the properties of water “explained away” when we reduced it to H2O? On the contrary, the phenomena of both are still with us and it is ridiculous to assume that if neuroscience is successful it will reduce the mind to “just a trick”. On the contrary, the mind will be seen as a complicated set of cognitive phenomena not just “reducible to” but explained by mechanisms in the brain/body system.

So, the question isn’t as Lehrer says whether or not neuroscience can move “beyond reductionism”, but rather, what can be successfully explained in mechanistic terms and what can’t? It is clear that there is useful phenomenological data to be had at the higher levels of abstractions that characterize our thoughts about the mind, but it should be said again that these abstractions aren’t “just” tricks, but rather, complicated phenomena in their own right that need explaining. Whether or not that explanation will be in the terms of neuroscience or at the higher level of cognitive psychology has yet to be determined, but it seems clear that the empirical method itself will give us a clearer picture of the mind.

This brings me to my last point, and that is whether or not neuroscience is capable, in principle, of explaining all cognitive phenomena. For me, the answer is a resolute yes, but I want to emphasize the term “in principle”, because explaining all cognitive phenomena at the molecular level may be pragmatically out of reach. We should be grateful that evolution has given us a language capable of discussing cognitive phenomena at a higher abstraction than that of science, but we should also learn to accept the fact that ultimately everything in the universe, including the mind, can be “reduced” to the physical motions of matter. It might seem like I am making a category mistake, but it seems intuitively plausible to me. I am not saying that all cognitive phenomena will be reduced to the physical level, but I think in principle, it can be. But I don’t think that is a very interesting idea. What is more interesting to me is the question of what will be explained in mechanistic terms and what won’t, and that is a pragmatic question of science that we will be continuously working on for what seems like an indefinite period of time.

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