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John von Neumann Thought He Had the Answers

The father of game theory helped develop the atom bomb—and thought he could calculate when to use it.

That certainty was also at the heart of Theory of Games and Economic Behavior, a text that von Neumann wrote jointly with the economist Oskar Morgenstern. (Incredibly, the book came together in the mid-1940s, even as von Neumann was shuttling between bomb labs and computer facilities.) Game theory, faithful to its name, treats every human context as a game—a self-contained situation in which your sly rival must lose for you to win, and in which the nature of these losses and wins can be always summed up in precise numbers. Morgenstern and von Neumann offered mathematical blueprints for victory, or at least for the least bruising of defeats. These weren’t just to be consulted by a pair of prisoners in separate cells, wondering whether to rat each other out—the Prisoner’s Dilemma, the classic thought experiment, framed in 1950 by Princeton mathematician Albert W. Tucker, that introduces game theory to students even today. For von Neumann, game theory was an affirmation of humans as rational actors who weigh utility and risk in a world that is perpetually zero-sum, and who can make optimal decisions—optimal, that is, for themselves—about bombing other countries or buying new cars.

When von Neumann framed (if only theoretically) the consumer as rational, he helped endorse the free market itself as a rational, self-correcting, self-optimizing place. But the real world and its various markets are bigger and more intricate than the models of game theory, of course: No one has perfect information or consistent beliefs, no one acts in the realm of unalloyed reason. One game theorist, Ariel Rubinstein, called his field “a collection of fables”—very useful for detached analysis, but useless to reach conclusions about “what to do tomorrow, or how to reach an agreement between the West and Iran.” Von Neumann implicitly wanted, however, to apply game theory to the full-blown war with the Soviet Union that he thought was imminent—and game theory recommended a surprise, preemptive attack by the United States. “If you say why not bomb them tomorrow, I say why not today?” he said in 1950. “If you say today at 5 o’clock, I say why not one o’clock?”

It’s hard to know if von Neumann truly believed that—and truly believed, more generally, that life and society are best organized by mathematical logic. He was fond of provocation, and his proposal of a lunchtime nuke over Moscow may have been made for sheer effect. But he also seemed to conduct his own affairs on the basis of pure mind. In his work, Macrae tells us, von Neumann never had strokes of irrational intuition, the kind that result in startling new ideas; his friend Einstein had many, and von Neumann envied them. With people, he was gregarious and charming, but “he tended to be oblivious to the emotional needs of those around him,” his daughter, Marina, said to Bhattachar­ya. (Marina was two when her parents divorced; her father agreed to let her live with him only after she turned 12, when she was “approaching the age of reason.”)