Complexity

No, what bothered him was the weird unreality of it all. The mathematical economists had been so successful at turning their discipline into ersatz physics that they had leached their theories clean of all human frailty and passion. (Location 233)

In mathematical terms, Prigogine's central point was that self-organization depends upon self-reinforcement: a tendency for small effects to become magnified when conditions are right, instead of dying away. It was precisely the same message that had been implicit in Jacob and Monod's work on DNA. And suddenly, says Arthur, "I recognized it as what in engineering we would have called positive feedback." Tiny molecular motions grow into convection cells. Mild tropical winds grow into a hurricane. Seeds and embryos grow into fully developed living creatures. Positive feedback seemed to be the sine qua non of change, of surprise, of life itself. (Location 463)

tiny events that have immense historical consequences—"These properties of increasing-returns economics shocked me at first," says Arthur. "But when I recognized that each property had a counterpart in the nonlinear physics I was reading, I got very excited. Instead of being shocked, I became fascinated." Economists had actually been talking about such things for generations, he learned. But their efforts had always been isolated and scattered. He felt as though he were recognizing for the first time that all these problems were the same problem. "I found myself walking into Aladdin's cave," he says, "picking up one treasure after another." (Location 517)

seriously began to think of abandoning economics and devoting himself full time again to his demographic research. His academic career seemed to be turning to ashes. All that kept him going was stubbornness. "I just pushed, and pushed, and pushed," he says. "I just kept believing that the system had to give somewhere." (Location 784)

It was disconcerting for the physicists only because they had spent the past 300 years having a love affair with linear systems—in which the whole is precisely equal to the sum of its parts. (Location 1022)

Sound is a linear system, which is why we can hear an oboe playing over its string accompaniment and recognize them both. The sound waves intermingle and yet retain their separate identities. Light is also a linear system, which is why you can still see the Walk/Don't Walk sign across the street even on a sunny day: the light rays bouncing from the sign to your eyes are not smashed to the ground by sunlight streaming down from above. The various light rays operate independently, passing right through each other as if nothing were there. (Location 1027)

The mind is an emergent property, the product of several billion neurons obeying the biological laws of the living cell. In fact, as Anderson pointed out in the 1972 paper, you can think of the universe as forming a kind of hierarchy: "At each level of complexity, entirely new properties appear. [And] at each stage, entirely new laws, concepts, and generalizations are necessary, requiring inspiration and creativity to just as great a degree as in the previous one. Psychology is not applied biology, nor is biology applied chemistry." (Location 1372)

As an example, he pointed to the visual hallucinations caused by peyote or LSD. These come in a variety of patterns, including lattices, spirals, and funnels, he said. And every, one of them could be explained as linear waves of electrical activity marching across the visual cortex of the brain. Might it be possible, he suggested, that these waves could be modeled with the kind of mathematical field theories used by physicists? (Location 1429)

In particular, the founding workshops made it clear that every topic of interest had at its heart a system composed of many, many "agents." These agents might be molecules or neurons or species or consumers or even corporations. But whatever their nature, the agents were constantly organizing and reorganizing themselves into larger structures through the clash of mutual accommodation and mutual rivalry. (Location 1490)

An autocatalytic set would even exhibit a primitive kind of reproduction: if a set from one little pond happened to slosh over into a neighboring pond—in a flood, say—then the displaced set could immediately start growing in its new environment. Of course, if another, different set were already in place, then the two would engage in a competition for resources. And that, Kauffman realized, would immediately open the door for natural selection to winnow and refine the sets. It was easy enough to imagine such a process selecting those sets that were more robust to environmental changes or that contained more efficient catalysts and more elaborate reactions or that contained more complex and sophisticated molecules. Ultimately, in fact, you could imagine the winnowing process giving rise to DNA and all the rest. The real key was to get an entity that could survive and reproduce; after that, evolution could do its work in comparatively short order. (Location 2148)

The existence of that phase transition would also help explain why trade is so important to prosperity, Kauffman told Arthur. Suppose you have two different countries, each one of which is subcritical by itself. Their economies are going nowhere. But now suppose they start trading, so that their economies become interlinked into one large economy with a higher complexity. "I expect that trade between such systems will allow the joint system to become supercritical and explode outward." Finally, an autocatalytic set can undergo exactly the same kinds of evolutionary booms and crashes that an economy does. (Location 2186)