The Smartest Man Who Ever Lived

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If the most dangerous invention to emerge from World War II was the atomic bomb, the computer now seems to be running a close second, thanks to recent developments in artificial intelligence. Neither the bomb nor the computer can be credited to, or blamed on, any single scientist. But if you trace the stories of these two inventions back far enough, they turn out to intersect in the figure of John von Neumann, the Hungarian-born polymath sometimes described as the smartest man who ever lived . Though he is less famous today than some of his contemporaries—Albert Einstein, J. Robert Oppenheimer, Richard Feynman—many of them regarded him as the most impressive of all. Hans Bethe, who won the Nobel Prize in Physics in 1967, remarked: “I have sometimes wondered whether a brain like von Neumann’s does not indicate a species superior to that of man.”

Born in Budapest in 1903, von Neumann came to the U.S. in 1930, and in 1933 he joined the Institute for Advanced Study, in Princeton, New Jersey. Like many émigré physicists, he consulted on the Manhattan Project , helping develop the implosion method used to detonate the first atomic bombs. Just weeks before Hiroshima, he also published a paper laying out a model for a programmable digital computer. When Los Alamos National Laboratory got its first computer, in 1952, it was built on the design principles known as “ von Neumann architecture. ” The machine was jokingly christened MANIAC , and the full name followed, devised to fit the acronym: Mathematical Analyzer, Numerical Integrator, and Computer.

And that’s not all. Von Neumann also established the mathematical framework for quantum mechanics, described the mechanism of genetic self-replication before the discovery of DNA, and founded the field of game theory , which became central to both economics and Cold War geostrategy. By the time he died of cancer , in 1957, possibly due to radiation exposure at Los Alamos, he was one of the American government’s most valued advisers on nuclear weapons and strategy. His hospital bed at Walter Reed Army Medical Center was guarded by a security detail, to make sure he didn’t reveal any secrets in his delirium.

In his new novel, The MANIAC , the Chilean writer Benjamín Labatut suggests that the name of the computer von Neumann helped invent fits the physicist himself all too well. If our world often seems mad—if we are unable to distinguish the real from the virtual, avid for technological power we can’t use wisely, always coming up with new ways to destroy ourselves—then perhaps the great minds that invented our world could not have been entirely sane. But did the man who helped create nuclear weapons and artificial intelligence know that he was putting the human future in jeopardy? Or was the thrill of scientific discovery so intense that he didn’t care?

The MANIAC sets out to penetrate this mystery with imaginary testimonies by real people—siblings and teachers, colleagues and lovers—who knew von Neumann at different stages of his life. Labatut mingles biographical facts with fictional episodes and details to take us through each stage, from the child prodigy in Budapest to the dying man in Washington, D.C., raging as his mind erodes. Along the way, the scientific and mathematical background of von Neumann’s work is sketched in for a lay audience.

From the very beginning, Labatut makes it clear that von Neumann is no ordinary human being. His mother jots down notes on his development, as in a baby book: “Did not cry after doctor’s slap / Unnerving / Looked more like middle-aged man not newborn.” His math professor tells the class about an “exceedingly difficult” theorem that no one has been able to prove, only to see the boy raise his hand, go to the chalkboard, and write down a complete proof: “Years, all my years of work, passed by in a second … After that, I was afraid of von Neumann.”

Even as the novel trains its focus on von Neumann, however, its structure keeps him at a distance; he is not a person we come to know so much as a problem we need to solve. The problem, all of the narrators agree, is that his genius was exhilarating and frightening in equal measure. “What he could do. It was so rare and beautiful that to watch him was to weep,” his math tutor says. “Yes, I saw that, but I also saw something else. A sinister, machinelike intelligence that lacked the restraints that bind the rest of us.”

[ From the June 2018 issue: Henry A. Kissinger on how the Enlightenment ends ]

Labatut is intent on casting von Neumann as a Faustian figure, a man who transgressed the limits of knowledge to become something more and less than human. This idea may be Labatut’s greatest departure from biographical fact. In reality, the “maniac” seems to have impressed people with his cheerfulness and zest for life. In Ananyo Bhattacharya’s 2022 biography, The Man From the Future , von Neumann is described by his friend and fellow physicist Eugene Wigner as “a cheerful man, an optimist who loved money and believed firmly in human progress.” By contrast, the Wigner who narrates several sections of The MANIAC speaks of von Neumann as a “luciferin” figure who “ranged beyond what was reasonable, until he finally lost himself.”

Labatut’s dark vision of modern science, and the way he skillfully distorts von Neumann’s biography to communicate that darkness, will be familiar to readers of When We Cease to Understand the World , his first work to be translated into English, in 2020. Blending biographical facts with outrageous fables, that novel offered miniature portraits of five 20th-century geniuses, including Fritz Haber, a chemist who invented both new fertilizers and chemical weapons , and Werner Heisenberg, the pioneer of quantum mechanics. The narrative technique owes a good deal to W. G. Sebald, who loved to ruminate on strange and troubling episodes from history, blurring the boundary between fact and fiction .

Labatut, however, is far freer in his distortions, which become more flamboyant and surreal with each section of the book. He depicts some of the most important figures in 20th-century science as haunted men, driven to madness by their pursuit of total knowledge. By the time we read that the French physicist Louis de Broglie, traumatized by the suicide of his best friend, commissioned an insane artist to create a replica of Notre-Dame Cathedral made of human feces, we are clearly in the realm of fable.

Yet the truly shocking thing is how many of the horrors described in When We Cease to Understand the World are entirely factual. The first gas attack in history, during the Battle of Ypres in 1915 , actually did make “hundreds of men [fall] to the ground convulsing, choking on their own phlegm, yellow mucus bubbling in their mouths, their skin turning blue from lack of oxygen.” And Haber’s wife, Clara, really did shoot herself in the heart, bleeding to death in the arms of her young son, possibly out of guilt over her husband’s role in creating gas warfare. When Labatut tells the story of 20th-century science as a dark parable, he is extrapolating from history but not entirely falsifying it.

The MANIAC opens with a short, third-person narrative that has no explicit connection with the life of John von Neumann, but would have fit perfectly in the earlier book. It is the true story of Paul Ehrenfest, an Austrian physicist who was a friend of Einstein’s, and whose life ended in an act of horror : In 1933, he killed his 15-year-old son, Wassik, who lived in an institution for children with Down syndrome, and then himself. Though Ehrenfest lived in the Netherlands, Labatut suggests that he may have been motivated by fear of the Nazis, who had come to power in Germany earlier that year and passed a new law mandating the forced sterilization of people with disabilities. In Labatut’s telling, Ehrenfest’s act was a premonition not just of Nazi crimes, but of the terrifying development of modern science. He could think of no better way to keep his son “safe from the strange new rationality that was beginning to take shape all around them, a profoundly inhuman form of intelligence that was completely indifferent to mankind’s deepest needs.” For Ehrenfest, the most disturbing thing about this monstrous spirit is that it springs from within science itself, “hovering over his colleagues’ heads at meetings and conferences, peering over their shoulders … a truly malignant influence, both logic-driven and utterly irrational, and though still fledgling and dormant it was undeniably gathering strength, wanting desperately to break into the world.”

Ehrenfest’s response is an act of madness, but Labatut suggests that von Neumann’s failure to be disturbed by the rise of the “inhuman” betrays an even deeper madness. Like the sorcerer’s apprentice, von Neumann helped the malignant spirit of modern science “break into the world” without thinking about the price the world would pay. “The problem with those games, the many terrible games that spring forth from humanity’s unbridled imagination,” his wife, Klara, muses, “is that when they are played in the real world … we come face-to-face with dangers that we may not have the knowledge or the wisdom to overcome.”

The MANIAC drives this point home in a variety of ways, starting with an early-childhood memory shared by von Neumann’s brother Nicholas. One night, their banker father brought home a Jacquard loom, which could be “programmed” to weave different patterns using sets of punch cards—a kind of primitive ancestor of the computer. The young János—his original Hungarian name, later Americanized to John—grows obsessed with the device, refusing to eat or sleep while he tinkers with it, trying to learn how it works. Soon the boy panics, fearing that he won’t be able to put the loom back together and it will be taken away: “He said that he simply could not part with the machine.” The details of János’s experience are imaginary, but the episode allows Labatut to offer a tidy preview of von Neumann’s fatal flaw, as well as a little lesson in computer history.

[ From the May 1964 issue: The computers of tomorrow ]

This is a much tamer kind of fictionalizing than in When We Cease to Understand the World , and in general The MANIAC feels like a more accessible and conventional treatment of its predecessor’s basic idea—the moral corruption at the core of modern science. This is partly because Labatut has set himself a more difficult narrative challenge by focusing on a single life at greater length. He has to convey biographical details about von Neumann to readers who have never heard of him, introduce complex concepts from a range of scientific fields, and simultaneously weave all this information into a moody allegory about knowledge and transgression.

This means the literary spell is often broken by sentences that sound like they could have come from a textbook (“In 1901, Bertrand Russell, one of Europe’s foremost logicians, discovered a fatal paradox in set theory”), and others that could be intoned in a movie preview (“He was the smartest human being of the 20th century … His name was Neumann János Lajos. A.k.a. Johnny von Neumann”). The fact that The MANIAC is Labatut’s first book written in English, rather than Spanish, may also play a role in this tonal unevenness.

T he MANIAC describes von Neumann’s work on the atomic bomb, but it strongly suggests that his most troublingly inhuman achievement was laying the groundwork for artificial intelligence. Late in the novel, we learn about von Neumann’s work on cellular automata, which combined two of his major interests: computing and game theory. In his book Theory of Self-Reproducing Automata , he imagined a grid of cells in which each cell changed its state—say, from “on” to “off,” or from one color to another—according to inputs received from its neighbors. Essentially, this was a way of modeling how systems could evolve from simplicity to complexity based on what we now call an algorithm, the iterative application of a set of rules. The concept has been highly influential in the study of both biological life and artificial intelligence.

[ From the September 2023 issue: Does Sam Altman know what he’s creating? ]

In addition to explaining the basics of cellular automata, Labatut turns the idea into a symbol of von Neumann’s failure to respect the difference between the gamelike abstractions of mathematics and the messy seriousness of human life. So it is poetic justice when Klara, infuriated by her husband’s “pigheadedness,” takes a printout of his work—“gorgeous filigrees of dots and lines that intermingled, fused, and then tore apart like the teeth of a broken zipper”—and sets it on fire in a trash can. It is another episode invented to point a moral: When science is inhumane, humanity has the right to take its revenge.

Yet in the long term, Labatut suggests, it may be humanity that has to submit. After bringing von Neumann’s story to a close, The MANIAC pivots to a lengthy postlude about Go, the ancient Chinese board game in which players take turns placing black and white stones on a board, capturing an opponent’s territory by surrounding it. In 2016, Lee Se-dol of South Korea, one of the world’s top-ranked Go players, was challenged to a match against AlphaGo , an AI developed by Google’s DeepMind. Garry Kasparov had lost a chess match to IBM’s Deep Blue 20 years earlier, but Go players were confident that their game was so much more complex that no machine could master it. Like so many skeptics before and since, they were proved wrong; AlphaGo won the match, taking four games to Lee’s one.

After telling von Neumann’s life story in about 200 pages, The MANIAC devotes its last 80 pages to this match. The effect is anticlimactic, but clearly Labatut sees the episode as the culmination of the book’s tragic arc. Ehrenfest dreaded the emergence of an inhuman intelligence, von Neumann made that emergence possible, and now Lee sees it taking place in front of him.

“When future historians look back at our time and try to pin down the first glimmer of a true artificial intelligence,” Labatut writes, “they may well find it in a single move during the second game between Lee Sedol and AlphaGo.” That move was so radically unexpected that it seemed to throw thousands of years of Go tradition out the window; no human watching the game could understand the justification for it, yet it led to the computer’s victory. By the end of the fifth game, Lee no longer hoped to win, only to postpone defeat. Labatut imagines one Go official’s view on the matter, saying, “There’s no point in playing out the endgame if you know you’re going to lose, right?” Today, when AI is on the cusp of making everyone from coders to truck drivers obsolete, that question feels more uncomfortably relevant than ever.

The MANIAC doesn’t quite say that this is all John von Neumann’s fault, and of course it isn’t. The really frightening thing is that even such a great mind can do relatively little to hasten or slow the progress of science. If von Neumann had never lived, someone else would likely have made his discoveries at about the same time, the way Gottfried Leibniz and Isaac Newton both invented calculus and Charles Darwin and Alfred Russel Wallace both came up with the theory of evolution. “It is not the particularly perverse destructiveness of one specific invention that creates danger,” an observer in the novel says of von Neumann. “The danger is intrinsic. For progress there is no cure.”

This article appears in the November 2023 print edition with the headline “The Smartest Man Who Ever Lived.”