Now let’s return to the careenium and talk about what happens in it. The way I’ve portrayed it so far focuses on the simms and their dashing and bashing. The simmballs are also present, but they serve a similar function to the walls — they are just big stationary objects off of which the simms bounce. In my mind’s eye, I often see the simms as acting like the silver marbles in a pinball machine, with the simmballs acting like the “pins” — that is, the larger stationary cylindrical objects which the marbles strike and ricochet off of as they roll down the sloped board of play.
But now I’m going to describe a different way of looking at the careenium, which is characterized by two perceptual shifts. First, we shift to time-lapse photography, meaning that imperceptibly slow motions get speeded up so as to become perceptible, while fast motions become so fast that they are not even seen as blurs — they become imperceptible, like the spinning blades of an electric fan. The second shift is that we spatially back away or zoom out, thus rendering simms too small to be seen, and so the simmballs alone necessarily become our focus of attention.
Now we see a completely different type of dynamics on the table. Instead of seeing simms bashing into what look like large stationary blobs, we realize that these blobs are not stationary at all but have a lively life of their own, moving back and forth across the table and interacting with each other, as if there were nothing else on the table but them. Of course we know that deep down, this is all happening thanks to the teeny-weeny simms’ bashing-about, but we cannot see the simms any more. In our new way of seeing things, their frenetic careening-about on the table forms nothing but a stationary gray background.
Think of how the water in a glass sitting on a table seems completely still to us. If our eyes could shift levels (think of the twist that zooms binoculars in or out) and allow us to peer at the water at the micro-level, we would realize that it is not peaceful at all, but a crazy tumult of bashings of water molecules. In fact, if colloidal particles are added to a glass of water, then it becomes a locus of Brownian motion, which is an incessant random jiggling of the colloidal particles, due to a myriad of imperceptible collisions with the water molecules, which are far tinier. (The colloidal particles here play the role of simmballs, and the water molecules play the role of simms.) The effect, which is visible under a microscope, was explained in great detail in 1905 by Albert Einstein using the theory of molecules, which at the time were only hypothetical entities, but Einstein’s explanation was so far-reaching (and, most crucially, consistent with experimental data) that it became one of the most important confirmations that molecules do exist.
Who Shoves Whom Around inside the Careenium?
And so we finally have come to the crux of the matter: Which of these two views of the careenium is the truth? Or, to echo the key question posed by Roger Sperry, Who shoves whom around in the population of causal forces that occupy the careenium? In one view, the meaningless tiny simms are the primary entities, zipping around like mad, and in so doing they very slowly push the heavy, passive simmballs about, hither and thither. In this view, it is the tiny simms that shove the big simmballs around, and that is all there is to it. In fact, in this view the simmballs are not even recognized as separate entities, since anything we might say about their actions is just a shorthand way of talking about what simms do. From this perspective, there are no simmballs, no symbols, no ideas, no thoughts going on — just a great deal of tumultuous, pointless careening-about of tiny, shiny, magnetic spheres.
In the other view, speeded up and zoomed out, all that is left of the shiny tiny simms is a featureless gray soup, and the interest resides solely in the simmballs, which give every appearance of richly interacting with each other. One sees groups of simmballs triggering other simmballs in a kind of “logic” that has nothing to do with the soup churning around them, except in the rather pedestrian sense that the simmballs derive their energy from that omnipresent soup. Indeed, the simmballs’ logic, not surprisingly, has to do with the concepts that the simmballs symbolize.
The Dance of the Simmballs
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.
The simms are still there, to be sure, but they are simply serving the simmballs’ dance, allowing it to happen, with the microdetails of their bashings being no more relevant to the ongoing process of cognition than the microdetails of the bashings of air molecules are relevant to the turning of the blades of a windmill. Any old air-molecule bashings will do — the windmill will turn no matter what, thanks to the aerodynamic nature of its blades. Likewise, any old simm-bashings will do — the “thoughtmill” will churn no matter what, thanks to the symbolic nature of its simmballs.
If any of this strikes you as too far-fetched to be plausible, just return to the human brain and consider what must be going on inside it in order to allow our thinking’s logic to take place. What else is going on inside every human cranium but some story like this?
Of course we have come back to the question that that long-agoshelved book’s title made me ask, and the question that Roger Sperry also asked: Who is shoving whom about in here? And the answer is that it all depends on what level you choose to focus on. Just as, on one level, the primality of 641 could legitimately be said to be shoving about dominos in the domino-chain network, so here there is a level on which the meanings attached to various simmballs can legitimately be said to be shoving other simmballs about. If this all seems topsy-turvy, it certainly is — but it is nonetheless completely consistent with the fundamental causality of the laws of physics.
CHAPTER 4
Loops, Goals, and Loopholes
The First Flushes of Desire
WHEN the first mechanical systems with feedback in them were designed, a set of radically new ideas began coming into focus for humanity. Among the earliest of such systems was James Watt’s steam-engine governor; subsequent ones, which are numberless, include the float-ball mechanism governing the refilling of a flush toilet, the technology inside a heat-seeking missile, and the thermostat. Since the flush toilet is probably the most familiar and the easiest to understand, let’s consider it for a moment.
A flush toilet has a pipe that feeds water into the tank, and as the water level rises, it lifts a hollow float. Attached to the rising float is a rigid rod whose far end is fixed, so that the rod’s angle of tilt reflects the amount of water in the tank. This variable angle controls a valve that regulates the flow of water in the pipe. Thus at a critical level of filling, the angle reaches a critical value and the valve closes totally, thereby shutting off all flow in the pipe. However, if there is leakage from the tank, the water level gradually falls, and of course the float falls with it, the valve opens, and the inflow of water is thereby turned back on. Thus one sometimes gets into cyclic situations where, because a little rubber gizmo didn’t land exactly centered on the tank’s drain right after a flush, the tank slowly leaks for a few minutes, then suddenly fills for a few seconds, then again slowly leaks for a few minutes, then again fills for a few seconds, and so on, in a cyclic pattern that somewhat resembles breathing, and that never stops — that is, not until someone jiggles the toilet handle, thus jiggling the rubber gizmo, hopefully making it land properly on the drain, thus fixing the leak.
Once a friend of mine who was watching my house while I was away for a few weeks’ vacation flushed the toilet on the first day and, by chance, the little rubber gizmo didn’t fall centered, so this cycle was entered. My friend diligently returned a few times to check out the house but he never noticed anything unto
ward, so the toilet tank kept on leaking and refilling periodically for my entire absence, and as a result I had a $300 water bill. No wonder people are suspicious of feedback loops!
We might anthropomorphically describe a flush toilet as a system that is “trying” to make the water reach and stay at a certain level. Of course, it’s easy to bypass such anthropomorphic language since we effortlessly see how the mechanism works, and it’s pretty clear that such a simple system has no desires; even so, when working on a toilet whose tank has sprung a leak, one might be tempted to say the toilet is “trying” get the water up to the mark but “can’t”. One doesn’t truly impute desires or frustrations to the device — it’s just a manner of speaking — but it is a convenient shorthand.
A Soccer Ball Named Desire
Why does this move to a goal-oriented — that is, teleological — shorthand seem appealing to us for a system endowed with feedback, but not so appealing for a less structured system? It all has to do with the way the system’s “perceptions” feed back (so to speak) into its behavior. When the system always moves towards a certain state, we see that state as the system’s “goal”. It is the self-monitoring, self-controlling nature of such a system that tempts us to use teleological language.
But what kinds of systems have feedback, have goals, have desires? Does a soccer ball rolling down a grassy hill “want” to get to the bottom? Most of us, reflexively recoiling at such a primitive Aristotelian conception of why things move, would answer no without hesitation. But let’s modify the situation just a tiny amount and ask the question again.
What about a soccer ball zipping down a long, narrow roadside gutter having a U-shaped cross-section — is it seeking any goal? Such a ball, as it speeds along, will first roll up one side of the gutter and then fall back to the center, cross it and then roll up the other side, then again back down, and so forth, gradually converging from a sinusoidal pathway wavering about the gutter’s central groove to a straight pathway at the bottom of the gutter. Is there “feedback” here or not? Is this soccer ball “seeking” the gutter’s mid-line? Does it “want” to be rolling along the gutter’s valley? Well, as this example and the previous one of the ball rolling down a hill show, the presence or absence of feedback, goals, or desires is not a black-and-white matter; such things are judgment calls.
The Slippery Slope of Teleology
As we move to systems where the feedback is more sophisticated and its mechanisms are more hidden, our tendency to shift to teleological terms — first the language of goals and then the language of “wishing”, “desiring”, “trying” — becomes ever more seductive, ever harder to resist. The feedback doesn’t even need to be very sophisticated, as long as it is hidden.
In San Francisco’s Exploratorium museum, there is an enclosure where people can stand and watch a spot of red light dancing about on the walls and floor. If anyone tries to touch the little spot, it darts away at the last moment. In fact, it dances about in a way that seems to be teasing the people chasing it — sometimes stopping completely, taunting them, daring them to approach, and then flitting away just barely in time. However, despite appearances, there is no hidden person guiding it — just some simple feedback mechanisms in some circuitry monitoring the objects in the enclosure and controlling the light beam. But the red spot seems for all the world to have a personality, an impish desire to tease people, even a sense of humor! The Exploratorium’s red dot seems more alive than, say, a mosquito or a fly, both of which attempt to avoid being swatted but certainly don’t have any detectable sense of humor.
In the video called “Virtual Creatures” by Karl Sims, there are virtual objects made out of a few (virtual) tubes hinged together, and these objects can “flap” their limbs and thus locomote across a (virtual) flat plane. When they are given a rudimentary sort of perception and a simple feedback loop is set up that causes them to pursue certain kinds of resources, then the driven manner in which they pursue what looks like food and frantically struggle with “rivals” to reach this resource gives viewers an eerie sensation of witnessing primitive living creatures engaged in life-and-death battles.
On a more familiar level, there are plants — consider a sunflower or a growing vine — which, when observed at normal speed, seem as immobile as rocks and thus patently devoid of goals, but when observed in time-lapse photography, seem all of a sudden to be highly aware of their surroundings and to possess clear goals as well as strategies to reach them. The question is whether such systems, despite their lack of brains, are nonetheless imbued with goals and desires. Do they have hopes and aspirations? Do they have dreads and dreams? Beliefs and griefs?
The presence of a feedback loop, even a rather simple one, constitutes for us humans a strong pressure to shift levels of description from the goalless level of mechanics (in which forces make things move) to the goal-oriented level of cybernetics (in which, to put it very bluntly, desires make things move). The latter is, as I have stressed, nothing but a more efficient rewording of the former; nonetheless, with systems that possess increasingly subtle and sophisticated types of feedback loops, that shorthand’s efficiency becomes well-nigh irresistible. And eventually, not only does teleological language become indispensable, but we cease to realize that there could be any other perspective. At that point, it is locked into our worldview.
Feedback Loops and Exponential Growth
The type of feedback with which we are all most familiar, and probably the case that gave it its name, is audio feedback, which typically takes place in an auditorium when a microphone gets too close to a loudspeaker that is emitting, with amplification, the sounds picked up by the microphone. In goes some sound (any sound — it makes no difference), out it comes louder, then that sound goes back in, comes out yet louder, then back in again, and all of a sudden, almost out of nowhere, you have a loop, a vicious circle, producing a terrible high-pitched screech that makes the audience clap their hands over their ears.
This phenomenon is so familiar that it seems to need no comment, but in fact there are a couple of things worth pointing out. One is that each cycling-around of any input sound would theoretically amplify its volume by a fixed factor, say k — thus, two loops would amplify by a factor of k2, three loops by k3, and so on. Well, we all know the power of exponential growth from hearing horror stories about exponential growth of the earth’s population or some such disaster. (In my childhood, the power of exponentials was more innocently but no less indelibly imprinted on me by the story of a sultan who commanded that on each square of a chessboard there be placed twice as many grains of rice as on the previous square — and after less than half the board was full, it was clear there was not nearly enough rice in the sultanate or even the whole world to get anywhere close to the end.) In theory, then, the softest whisper would soon grow to a roar, which would continue growing without limit, first rendering everyone in the auditorium deaf, shortly thereafter violently shaking the building’s rafters till it collapsed upon the now-deaf audience, and then, only a few loops later, vibrating the planet apart and finishing up by annihilating the entire universe. What is specious about this apocalyptic scenario?
Fallacy the First
The primary fallacy in this scenario is that we have not taken into account the actual device carrying out the exponential process — the sound system itself, and in particular the amplifier. To make my point in the most blatant manner, I need merely remind you that the moment the auditorium’s roof collapsed, it would land on the amplifier and smash it to bits, thus bringing the out-of-control feedback loop to a swift halt. The little system contains the seeds of its own destruction!
But there is something specious about this scenario, too, because as we all know, things never get that far. The auditorium never collapses, nor are the audience members deafened by the din. Something slows down the runaway process far earlier. What is that thing?
Fallacy the Second
The other fallacy in our reasoning also involves a type
of self-destruction of the sound system, but it is subtler than being smashed to smithereens. It is that as the sound gets louder and louder, the amplifier stops amplifying with that constant factor of k. At a certain level it starts to fail. Just as a floored car will not continue accelerating at a constant rate (reaching 100 miles per hour, then 200, 300, 400, soon breaking the sound barrier, etc.) but eventually levels out at some peak velocity (which is a function of road friction, air resistance, the motor’s internal limits, and so forth), so an amplifier will not uniformly amplify sounds of any volume but will eventually saturate, giving less and less amplification until at some volume level the output sound has the same volume as the input sound, and that is where things stabilize. The volume at which the amplification factor becomes equal to 1 is that of the familiar screech that drives you mad but doesn’t deafen you, much less brings the auditorium crashing down on your head.
And why does it always give off that same high-pitched screeching sound? Why not a low roar? Why not the sound of a waterfall or a jet engine or long low thunder? This has to do with the natural resonance frequency of the system — an acoustic analogue of the natural oscillation frequency of a playground swing, roughly once every couple of seconds. An amplifier’s feedback loop has a natural oscillation frequency, too, and for reasons that need not concern us, it usually has a pitch close to that of a high-frequency scream. However, the system does not instantly settle down precisely on its final pitch. If you could drastically slow down the process, you would hear it homing in on that squealing pitch much as the rolling soccer ball seeks the bottom of the gutter — namely, by means of a very rapid series of back-and-forth swings in frequency, almost as if it “wanted” to reach that natural spot in the sonic spectrum.
I Am a Strange Loop Page 9
