Simon’s ant is a well-known thought experiment from Chapter 3, “The Psychology of Thinking: Embedding Artifice in Nature,” in Herbert A. Simon, The Sciences of the Artificial, 1981. It’s a parable about computation, about how computational requirements depend on the problem to be solved. Stated that way, it is an obvious truism. But Simon’s thought experiment invites you to consider this truism where the “problem to be solved” is an environment external to the computer – it is thus reminiscent of Braitenberg’s primitive vehicles (which I discussed in Part 1).
Think of it like this: the nervous system requires environmental support if it is to maintain its physical stability and operational coherence. Note that Simon was not at all interested in the physical requirements of the nervous system. Rather, he was interested in suggesting that we can get complex behavior from relatively simple devices, and simplicity translates into design requirements for a nervous system.
Simon asks us to imagine an ant moving about on a beach:
We watch an ant make his laborious way across a wind- and wave-molded beach. He moves ahead, angles to the right to ease his climb up a steep dunelet, detours around a pebble, stops for a moment to exchange information with a compatriot. Thus he makes his weaving, halting way back to his home. So as not to anthropomorphize about his purposes, I sketch the path on a piece of paper. It is a sequence of irregular, angular segments--not quite a random walk, for it has an underlying sense of direction, of aiming toward a goal.
After introducing a friend, to whom he shows the sketch and to whom he addresses a series of unanswered questions about the sketched path, Simon goes on to observe:
Viewed as a geometric figure, the ant’s path is irregular, complex, hard to describe. But its complexity is really a complexity in the surface of the beach, not a complexity in the ant. On that same beach another small creature with a home at the same place as the ant might well follow a very similar path.
I want to examine a variation on his parable. What would happen if we put the ant on an absolutely featureless surface and let it walk about? What kind of paths would it trace then? As that surface lacks any of the cues typical of the ant’s environment I imagine the ant would either not move at all or move in a genuinely random or perhaps a rigidly stereotypic way (e.g. around and around in a circle). Or perhaps the ant would hallucinate.
That’s what interests me. But not ants.
Nor, of course, was Simon particularly interested in ants. He only told that story to make a point he wanted to apply to the human case. So let us continue on and consider the human case. What happens to us when we face a blank world, a world that does not support our intentionality, that doesn’t supply the “informatic pressure” the mind needs to hold its shape?
What happens is that the mind becomes unstable.
Early on in The Ghost Dance, a classic anthropological study of the origins of religion, Weston La Barre considers what happens under various conditions of deprivation. Consider this passage about Captain Joshua Slocum, who sailed around the world alone at the turn of the 20th Century:
Once in a South Atlantic gale, he double-reefed his mainsail and left a whole jib instead of laying-to, then set the vessel on course and went below, because of a severe illness. Looking out, he suddenly saw a tall bearded man, he thought at first a pirate, take over the wheel. This man gently refused Slocum’s request to take down the sails and instead reassured the sick man he would pilot the boat safely through the storm. Next day Slocum found his boat ninety-three miles further along on a true course. That night the same red-capped and bearded man, who said he was the pilot of Columbus’ Pinta, came again in a dream and told Slocum he would reappear whenever needed.
La Barre goes on to cite similar experiences happening to other explorers and to people living in isolation, whether by choice, as in the case of religious meditation, or force, as in the case of prisoners being brainwashed.
Imagine, now, that when you step away from the world, you fill the void with a work of imaginative literature. How does that work support the operations of the nervous systems, giving them resistance and structure so they don’t flail into chaos?
And what can we learn about the mind by examining the traces it leaves in the world in the absence of any environmental pressure other than that from the medium of inscription? Is there any better way to examine the mind itself?
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