I can calculate the movement of the stars but not the madness of men

From Future Babble by Dan Gardner.

This put an interesting gloss on an argument made by the philosopher Karl Popper decades before the development of chaos and complexity theory. "The course of human history is strongly influenced by the growth of human knowledge," Popper wrote. But it's impossible to "predict, by rational or scientific methods, the future growth of our scientific knowledge: because doing so would require us to know that future knowledge, and, if we did, it would be present knowledge, not future knowledge." Popper's case was strong when he first made it in the 1930s, and the decades since have produced an abundance of failed predictions to bolster it. And now that we know that the individual human brain is nonlinear and literally unpredictable, Popper is looking better than ever. This may seem a terribly abstract and theoretical point, but it's not. It has big, practical implications. Consider the case of the Anaconda Copper Mining Company. All but forgotten today, Anaconda was once one of the largest companies in the world thanks to its dominance of the expanding market for copper telephone wires. "This company will still be going strong one hundred or even five hundred years from now," boasted Anaconda's president in 1968. There was likely a touch of fear in his bravado. Three years earlier, the brains of two British scientists had figured out how fiber optics could theoretically be a medium of communication. And two years after his boast, three scientists were able to make fiber optics a practical technology vastly superior to copper wires. The price of copper plummeted. Facing liquidation, anaconda sold itself in 1977.

It's hard to imagine a better demonstration of Popper's argument and the critical role played by the unpredictable brain. As Sir Isaac Newton himself observed - after losing a bundle in one of history's first stock bubbles - "I can calculate the movement of the stars but not the madness of men." Centuries later, that is still true.