Buchanan, a writer for Nature and a theoretical physicist, summarizes the law of universality, a sweeping concept that is very much a work in progress.
The frequency of observable physical phenomena such as earthquakes and forest fires may also describe the frequency of wars and stock-market crashes, an astounding proposition on the face of it. To make his case, Buchanan first draws from Bak, Tang, and Weisenfeld’s computer modeling of a sandpile, where grains of sand are dropped one at a time until “avalanches” result. The sandpile at last reaches a state of “self-organized criticality,” in which an avalanche is always possible. But even though there are many more small avalanches than large ones, large and small avalanches are always possible, and can happen anywhere in the mass that is in a critical state. The model explains why earthquakes are impossible to predict, since faultlines are always in a critical state; or why forest fires can break out anywhere in the at-risk area, and can be small and containable, or large and beyond control, like the Yellowstone fire of 1988. Buchanan’s speculations on human events seem dicier, though fascinating. The first world war, for instance, broke out when the countries of Europe were in self-organized criticality. War might have begun when an army invaded another country; instead, a major avalanche resulted when King Archibald Ferdinand’s chauffeur turned up a wrong street and ran into an assassin. Anything could have started the war, in other words. In a corollary argument, Buchanan contemptuously dismisses the “great man” theory of history, whereby Einstein or Churchill make all the difference, instead arguing that great men are, in effect, catalysts of the critical mass. Cautionary but entertaining, Buchanan extends his thesis to fluctuations of the stock market, the migrations of peoples, and even the advance of science itself.
It’s impossible to say whether the social side of Buchanan’s fatalistic thesis will prove elaborately wrong, though he argues it with fervor and elegance.