Complexity theory is “the ultimate of interdisciplinary fields.” It “has blossomed into a broad movement of scientists searching for universal patterns that occur at all levels of nature and society when local interactions give rise to new collective behaviors. They want to know, for example, how millions of amoebas swarm into a self-directed slime mold, how a trillion-celled organism develops from a single egg, and how markets arise from the interactions of individual human beings. Complexity theorists want to reproduce these patterns with computer models, in order to gain a kind of insight that equations or statistics supposedly cannot match. What’s more, they want to see both the forest and the trees, by viewing big patterns through the local rules of interaction that produce them.”