Complexity: The Emerging Science at the Edge of Order and Chaos

by M. Mitchell Waldrop

If the Santa Fe economists found the prospect exciting, however, they also found it vaguely disturbing. And the reason, says Arthur, was something that he didn't put his finger on until much later. "Economics, as it is usually practiced, operates in a purely deductive mode," he says. "Every economic situation is first translated into a mathematical exercise, which the economic agents are supposed to solve by rigorous, analytical reasoning. But then here were Holland, the neural net people, and the other machine-learning theorists. And they were all talking about agents that operate in an inductive mode, in which they try to reason from fragmentary data to a useful internal model." Induction is what allows us to infer the existence of a cat from the glimpse of a tail vanishing around a corner. Induction is what allows us to walk through the zoo and classify some exotic feathered creature as a bird, even though we've never seen a scarlet-crested cockatoo before. Induction is what allows us to survive in a messy, unpredictable, and often incomprehensible world.