Complex Systems

I'm reading Michael Crichton's last novel called Micro and I love the introduction. I'd like to post some of it here:

Perhaps the single most important lesson to be learned by direct experience is that the natural world, with all its elements and interconnections, represents a complex system and therefore we cannot understand it and we cannot predict its behavior. It is delusional to behave as if we can, as it would be delusional to behave as if we could predict the stock market, another complex system. If someone claims to predict what a stock will do in the coming days, we know that person is either a crook or a charlatan. If an environmentalist makes similar claims about the environment, or an ecosystem, we have not yet learned to see him as a false prophet or a fool.

Human beings interact with complex systems very successfully. We do it all the time. But we do it by managing them, not by claiming to understand them. Managers interact with the system: they do something, watch for the response, and then do something else in an effort to get the result they want. There is an endless iterative interaction that acknowledges we don't know for sure what the system will do--we have to wait and see. We may have a hunch we know what will happen. We may be right much of the time. But we are never certain. Interacting with the natural world, we are denied certainty. And always will be.