Snazzy and overarching scientific paradigms are notoriously tough to corral, but in his fine new book, Steven Johnson gets a good grip on one of the most important of late: "the eerie, invisible hand of self-organization." As Johnson explains with brainy but convivial clarity, self-organization describes systems, like slime molds or computer simulations, that generate rich and complicated global behavior without being controlled through hierarchical "top-down" commands. Instead, their behavior emerges, as if by magic, from the "bottom-up" interaction of a mess of relatively simple agents pursuing their own narrow agendas, with little or no... More >>>