Salat pao street vendor Chiang Mai, by Takeaway.
P: I noticed something the other day at the Trader Joe’s store. There are 10 different kinds of frozen pizza in one aisle.
M: Yeah, and there are more at Safeway. They do it to give more choices to consumers so they can sell more. Do you know how all those varieties are created? It is done by combining similar ingredients in different ways. Food combination was not always common in the culinary history. The early humans ate herbs, meat, and cereal separately. One day they accidently mixed meat and herbs together, and that was a breakthrough in the discovery of tasty bites. The Chinese bun, BaoZi 包子, has meat and vegetables wrapped in a layer of dough. This combo invention was wildly popular. Imitations soon followed. It is possible that imitations of BaoZi include egg rolls, burritos, sushi, shepherd’s pie, sandwich wraps, or even Middle Eastern shawarmas, as they all share a similar structure. The magic of combinations has created new looks, smells, and tastes that people love. Look at the upscale restaurants. Nouveau Cuisine is also about combinations, with emphasis on simple and fresh ingredients.
P: Come to think of it, it is not only about foods but clothing and more. The variety of dresses, hats, pants, are created by combinations of some fabrics and shapes. I don’t know how Mozart composed his music or Van Gogh painted his pictures. But presumably they did it in part by creative combinations of elements of their respective arts.
Organic Compound, by miguelferig.
M: Well, those are man-made stuff. Look at what Nature has. The combinations of four elements - carbon, hydrogen, oxygen, and nitrogen - make up organic matters that are the building blocks of lifeforms. From those combinations come sugars, fats, amino acids, proteins, cellulose, DNA, cells, tissues. Isn’t it amazing that myriads of living things have in common four elements: C, H, O, and N? That is probably why organic chemistry textbooks are so much thicker than the general chemistry ones. Because C-H-O-N combinations can far outnumber the finite properties and reactions of inorganic elements.
P: Organic chemistry is also about plastics and petrochemicals. I read a magazine story that says a lady in 1990s had tried to live without plastics for a week but couldn’t do it. Strangely, the combinations of organic elements remind me of the I-Ching hexagrams. They both are about combinations of simple elements.
Diagram of I Ching hexagrams owned by German mathematician Gottfried Wilhelm Leibniz, 1701
by Unknown - Perkins, Franklin. Leibniz and China: A Commerce of Light. Cambridge: Cambridge UP, 2004. 117.
M: Yes, that is so. The hexagrams are composed of six yao (爻) lines. Each yao line is either a solid line (yang 陽) or a broken line (yin 陰). So a hexagram is a stack of 6 yin-or-yang lines. There are 26 = 64 hexagrams. Each one has a name, and is a symbol for some phenomenon. For example, the fourth hexagram, Meng 蒙, is a symbol for not knowing and possible learning. Hexagrams are really permutations instead of combinations because permutation is more specific. One yin and five yang lines are one combination. But this combination has six possible permutations. What is mysterious about the I-Ching is how the ancients discovered or interpreted the elusive meanings behind each symbolic hexagram. How come this divination device worked so well in China? What is more, the principle of combination is also in many other fortune-telling devices: tarot cards, astrological charts. You can even create your own deck of tarot cards if you can cook up some new symbols and meanings.
Xiantianbagua 8 Trigrams, by Philolo.
P: Okay, what about diversity by permutations? Can you do that with your positive feedback loop?
M: Yes I thinking so. A positive feedback loop has two active systems, both amplifying attractive or repulsive differences. Permutations can be arranged on the sensory differences. Adding more systems allows more sensory permutations and more diverse relationships. For example, one permutation can be that the two systems amplifies different types of differences. One system amplifies attractive differences and the other repulsive differences. Such arrangement will be like a celebrity-paparazzi relationship. The star is repulsed and wants to get away from the paparazzi’s camera to protect privacy. And the paparazzi is attracted and wants to get closer to take pictures. This is similar to stalker-prey relationship. Wolves hunt deers. Ex-boyfriend follows the girl who wants to be left alone. I don’t know if parasite-host relationship is also this way, but at least one side is willing and the other not. Hunting and stalking are cruel, but they are also part of Nature.
Jongensspelen, chaser and chasee
by Anonymous - Jongensspelen. H.A.M. Roelants, Schiedam ca 1860-1870.
P: Okay, so a loop of one attractive system and one repulsive system makes up a chase-and-run relationship. How about if one system senses both repulsive and attractive differences? Is that a possible permutation?
M: Hmm. That would be like that system is having a mood swing. I can think of a yo-yo dieter in that kind of situation. He is at first attracted to the idea of diet and tries it. Then he is repulsed by the hardship of dieting and lapses back to overeating. After having gained weight he is again attracted to having a diet and thus back to square one. And so attraction and repulsion alternate in his mind.
The story of Hamlet by Shakespeare is another example of this. The prince of Denmark wailed ‘to be or not to be, that is the question’ as he pondered revenge to his father's death. In English there are words such as ambivalence, dilemma, and bipolar disorder to describe the various intensity levels of such mental (mood) swings.
David Garrick in Hamlet, Act I, Scene 4.
The chemistry Nobel laureate Prigogine is known for his study on dissipative structures, which start with a critical phase transition (e.g. water boiling). During this critical region a structure is alternating between two phases (e.g. water and steam). Such alternation is similar to mood swings during puberty and menopause, which are stages of transition. Risky choices are common during crisis, which is also a stage of transition. The Chinese word for crisis is 危機 (danger-opportunity), denoting that it is a fork to danger (危) and to opportunity (機) . To fight or to flee? To commitment or not to? To cover up or to be honest? Assessing hard choices is clearly stressful to the body as it copes with the mental swings and leaves dis-ease marks such as headache, ulcer, insomnia, irritation. This has prompted the rise of an industry called public relation or propaganda. Its service is to pacify the agony of hard choices by drawing attention to only one of the alternatives, for the sake of both the decision maker and the recipients. One glaring example of propaganda is the U.S. President Bush’s and U.K. Prime Minister Blair’s declaration of the threat of Iraqi weapons of mass destruction as they built up a coalition to invade Iraq in 2003.
What about the second system in the positive feedback loop? The second system can react to the oscillating first system by acts of propaganda. Or it can police or medicate the first system to reduce its oscillations. However, the second system cannot be indifferent to the first system’s changes. Because then the positive feedback loop is broken by the inaction.
Propaganda, policing, or medication are highly evolved devices that aren’t likely to be in the arsenal of the second system. A more likely scenario for the second system is that it reacts to the oscillations of the first system by itself oscillating. So in this permutation both systems are oscillating, although not likely to the same rhythm or melody. How do you call this type of oscillate-oscillate relationship? A dance, a resonance, a game?
Active Resonance - Flashdance
by Голубев Роман(ЛУЧШИЙ ВЕДУЩИЙ).
This game relationship is seen in all sorts of interactions. Examples are parents going nuts over teenagers’ erratic behaviors. Or bystanders dancing to the music of street performers. Or fish (or any animals) joining each other in unified yet irregular herd movements. It can also be police clashing against street protesters, opposing troops fighting in the battlefield, sports teams dueling on the scoreboard. Much studies on game (war) plans have been done to manage conflicts. Because each system can be lead to triumph or defeat, to joy or agony, to order or chaos, temporarily. Anyway, the outcome of such active systems resonances is unpredictable, like the butterfly effect on a game.
Active Resonance. A tornado of fish
by Bare Dreamer - Flickr.
P: Resonances of active systems? Hmm. Anyway, I wonder what is the basis for positive feedbacks. You mentioned that negative feedback is natural like the Chatelier’s Principle. But why is positive feedback naturally occurring?
M: Active resonances are closely tied to active sensors. That is an important basis for my sleuthing. We will get to that more later. Why are positive feedbacks naturally occurring? It seems that the cause is circular. Organizations (relationships, systems) arise from positive feedbacks, and positive feedbacks come out of organizations. I can say that since organization is natural, so positive feedback is also natural. Some people may not like circular reasoning. But I think it is a fundamental truth that things and reasons are circular in the biological world. The word ‘parents’ is meaningful because of the word ‘children’, and the word 'children' is meaningful because of the word 'parents'. What is the ‘left’ without the ‘right’? And what is the ‘right’ if it is not referenced to the ‘left’? Non-circular reasons are good for the inorganic fire and rock, the world depicted by the mathematics of Newton and Einstein. But non-circular reasons do not work in the circular biological world.
So how did positive feedback begin before there was any organization? That is a good old chicken-or-egg question. My guess is that it started with matters. Somehow it became possible for some matters to store energy (food). That turned those matters into active matters. In engineering terms, 'active' means that something has its own supply of energy for action. Whereas 'passive' means that a system depends on some other’s energy to react. We have talked about natural formation of loops before, like the water cycle. So together, a loop of circulation with two active units in it. That was when a positive feedback began to take place. Each active unit has stored energy for it to act on the feedback from the other. With this feedback loop diverging organizations emerged, followed by more complex positive feedbacks from the new organizations. It’s like two people A and B. A borrows money from B to start selling goods or services. B lends money to A to earn interests. As the money changes hands back and forth between the two, a positive feedback loop is formed as a business-finance partnership. A evolves into a store owner, and B to a banker. And they will continue to evolve to something else unless a negative feedback is established to stabilize their relationship.
There is a theory called Punctuated Equilibrium. It is an amendment to a problem in Darwin’s evolution theory. By mutations, competitions, and natural selection, the evolution of species should take place continuously over geological time. But that is not what is found buried under the earth. The fossil records show that the pace of evolutionary changes are step-like instead of gradual. Living species went through long periods of time with very little change (stasis, stability), followed by short periods of time with big changes (schismogenesis, instability), and then back to long periods of stasis again if big changes did not make them extinct. Paleontologists Stephen Jay Gould and Niles Eldredge noticed this and reported it with their theory of Punctuated Equilibrium.
Comparison between phyletic gradualism and punctuated equilibrium (Italian)
by Miguel Chavez, modified by SunOfErat.
With our feedback loops model, we can say that punctuated equilibrium is due to both positive and negative feedbacks at work. The long stasis periods of the mostly-similar fossils correspond to a time segment where negative feedbacks overpower positive feedbacks, so stability predominates. The short schismogenesis periods of the changing fossils correspond to a segment where positive feedbacks dominate over negative feedbacks, so transformation prevails.
We can shrink the time scale and still find this dynamics. The 4000 years of Chinese history is a series of dynasties. Each dynasty has about 200 - 400 years of stable regime. The transition from one dynasty to the next is a time of increasing revolts or invasions, lasting about 10 to 40 years. From one dynasty to revolution to the next dynasty, that is also a form of punctuated equilibrium.
A human life span is about 80 years. Childhood, adulthood, and senior-hood are relatively long and stable periods where the body doesn’t change much. But puberty and menopause are short transition periods where the body undergoes major changes. A U.S. President is in office for 4 or 8 years. During this time the government has a stable administration. Then comes the next election and campaign of some months. That is when the stability of an administration is punctuated by calls for change. There is a Chinese phrase that alludes to this phenomenon: Ten years on the east side of a river. Ten years on the west side of a river. 十年河東 十年河西. It means impermanence. By adding the crossing of a river, which presumably is much shorter than ten years, this phrase will match right on for punctuated equilibrium.
P: Okay. That is too much information. My mind cannot handle any more of these permutations. Anyway, we started by talking about memory. How do you use positive feedbacks to explain the mind or memory?
M: Well, Positive feedback loops alone are not enough to explain memory. Let us first take a closer look at the sensor / governor components of our active system. There is this resonance phenomenon that needs to be brought up. Then we will get into the circuitry of the brain and see how memories are formed there.
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