A prodigy on the Danube
John von Neumann was born Neumann János Lajos in Budapest on December 28, 1903, the eldest of three sons in a wealthy, non-observant Jewish family. His father, Miksa (Max) Neumann, was a banker with a doctorate in law; his mother, Margit Kann, came from a family whose business occupied the building in which three generations of Kanns lived. The Neumanns had an eighteen-room apartment on the top floor. In 1913 Emperor Franz Joseph raised Max to the Hungarian nobility, and the family took the title margittai, which János later rendered in German as “von.”
The boy was taught by governesses and tutors in English, French, German and Italian, read a forty-six-volume world history for pleasure, and was soon recognised as a prodigy. In 1914 he entered Budapest’s Lutheran Fasori Gimnázium, where Eugene Wigner, a future Nobel laureate, was a year ahead of him. His father arranged private instruction from the mathematician Gábor Szegő, whose wife recalled that after their first meeting Szegő came home with tears in his eyes at the boy’s talent. By nineteen von Neumann had published a paper giving the modern definition of ordinal numbers.
Two degrees at once
His father wanted him in a practical profession, so a compromise was struck: chemical engineering. Von Neumann took a two-year chemistry course in Berlin, then passed the entrance examination for the ETH in Zurich. At the same time he enrolled as a doctoral candidate in mathematics at the University of Budapest. In 1926 he received his engineering diploma in Zurich and, almost simultaneously, his doctorate in Budapest, with a thesis axiomatising set theory.
A Rockefeller grant took him to Göttingen to work with David Hilbert, then the centre of the mathematical world. He became the youngest Privatdozent in the history of the University of Berlin in 1928 and for a time produced nearly one major paper a month. In 1929 he moved to Princeton as a visiting lecturer, and in 1933, as the Nazis were driving Jewish scholars from German universities, he accepted a professorship at the newly founded Institute for Advanced Study, where he remained for the rest of his life.
Mathematician of everything
Von Neumann is often described as having the widest range of any mathematician of his time. He gave set theory a rigorous foundation; he was the first to define an abstract Hilbert space axiomatically; and in his 1932 book Mathematical Foundations of Quantum Mechanics he provided the first rigorous mathematical framework for the new physics. His 1932 papers on ergodic theory were, in the mathematician Paul Halmos’s words, enough on their own to guarantee “mathematical immortality.”
In 1928 he proved the minimax theorem, which shows that in two-person zero-sum games each player has a strategy that minimises his maximum possible loss. With the economist Oskar Morgenstern he expanded the idea into Theory of Games and Economic Behavior (1944), a book that drew a front-page story in The New York Times and founded game theory as a discipline. Its descendants now shape economics, auction design, evolutionary biology and nuclear strategy alike.
He kept opening new fields almost to the end. In lectures in 1948 and 1949 he asked how a machine could build a copy of itself, and with Ulam he created the theory of cellular automata, designing on paper a self-reproducing “universal constructor.” His logical analysis of self-replication, which required a stored description of the machine to be both copied and executed, anticipated the way DNA works before its structure was discovered in 1953.
The bomb
By the late 1930s von Neumann had become the leading authority on the mathematics of explosions and shaped charges, and he was drawn into the Manhattan Project as a consultant to Los Alamos. His central contribution was to the implosion method: he was among its most persistent advocates and helped design the explosive lenses that compressed the plutonium core of the Fat Man bomb dropped on Nagasaki. He also showed that a bomb would do more damage if detonated high above its target. On July 16, 1945, he watched the Trinity test in the New Mexico desert.
After the war he worked on the hydrogen bomb and, with his close friend Stanisław Ulam, developed the Monte Carlo method, which uses random sampling to approximate solutions to problems too complex to solve directly; it is now used everywhere from physics to finance.
The stored-program computer
Von Neumann’s wartime need for vast calculations led him to the ENIAC project at the University of Pennsylvania, where J. Presper Eckert and John Mauchly had built one of the first electronic computers. Their next machine, the EDVAC, was still being planned, and in 1945 von Neumann wrote an unfinished report on its design, circulated that June by the mathematician Herman Goldstine. The First Draft of a Report on the EDVAC described a machine that held both its data and its instructions in a single memory, read and executed by a central unit one step at a time. Earlier machines had been programmed by rewiring panels or feeding in paper tape; in the new design a program was simply more data that the computer could store and change.
The ideas were not his alone, and the report’s failure to credit Eckert and Mauchly caused lasting bitterness; its wide circulation also undermined their patent claims. But von Neumann’s lucid account spread the blueprint around the world. He then led the construction of the IAS computer at Princeton, built between 1946 and the early 1950s and copied at laboratories from Los Alamos to Stockholm and Sydney. He invented the merge sort algorithm in 1945, pioneered numerical analysis, and in 1950, with Jule Charney and colleagues, used ENIAC to make the first numerical weather forecasts.
What it gave the world
The design he described is now called the von Neumann architecture, and its logic sits inside almost every general-purpose computer built since: laptops, phones and data-centre servers all fetch instructions from memory and execute them in sequence in essentially the way the 1945 report set out. The weather forecasts on every phone descend from the numerical prediction he championed; in 1955 the Joint Numerical Weather Prediction Unit he helped bring about began routine computer forecasting in the United States. That same year he noted that carbon dioxide from burning coal and oil might already be warming the world.
Game theory, Monte Carlo simulation and the mathematics of quantum mechanics are each a toolkit used daily by scientists and engineers. Few people have left fingerprints on so many of the systems by which modern life is calculated.
A Jew from Budapest in an age of extremes
Von Neumann grew up in the cosmopolitan Jewish bourgeoisie of Budapest that also produced Wigner, Leo Szilard and Edward Teller, the émigré scientists nicknamed “the Martians.” His family’s Judaism was cultural rather than religious, and in 1930, shortly before marrying Marietta Kövesi, he was baptised a Catholic. Yet he kept a lifelong taste for Yiddish humour, and when Europe darkened he brought his mother, his brothers and his in-laws to the United States in 1939.
Having watched Nazism engulf Europe and Stalin’s Soviet Union expand after the war, he concluded that civilisation would survive only if the United States prevailed over totalitarianism of every kind. He told a Senate committee that he was “violently anti-communist, and much more militaristic than the norm” and by several accounts he advocated a preventive war against the Soviet Union in the late 1940s, a position that troubled many colleagues and remains part of his complicated legacy.
The man
Von Neumann always wore a formal suit, loved parties and off-colour jokes, and could reportedly lecture at 8:30 in the morning after socialising until the early hours. He worked best amid noise and was known in Princeton for playing German marches at high volume. He spoke Hungarian, German, French and English fluently and read the ancient Greek historians in the original. He was generous with his time, and Wigner judged that he had perhaps supervised, informally, more work than any other modern mathematician. The physicist Hans Bethe wondered aloud whether a brain like his indicated “a species superior to that of man.”
His first marriage, to Marietta Kövesi, produced a daughter, Marina, born in 1935, who became a professor and economist; the couple divorced in 1937. In 1938 he married Klára Dán, who went on to program the ENIAC and the MANIAC computers.
Last years
In the 1950s von Neumann was the most influential scientist in American defence. He chaired the committees that set the course of the country’s intercontinental ballistic missile programme and in 1955 became a commissioner of the Atomic Energy Commission. That year doctors found a cancer, possibly linked to his radiation exposure at Los Alamos, that had already spread. He received the Medal of Freedom and the Enrico Fermi Award in 1956. As death approached he asked for a Catholic priest but, by the priest’s account, found little comfort.
He died at Walter Reed Army Medical Center in Washington on February 8, 1957, aged fifty-three, and was buried in Princeton Cemetery. His legacy is double-edged, entwined with the weapons of the nuclear age as well as the machines of the information age. But the computer on which this page is being read is, at its logical core, the machine he described in 1945, and his conviction that hard problems could be conquered by computation became one of the defining ideas of the century that followed.
Sources & further reading
John von Neumann, Wikipedia · First Draft of a Report on the EDVAC, Wikipedia · IAS machine, Wikipedia · Quote Origin: For Progress There Is No Cure, Quote Investigator · Researched from the sources above and checked against them. Spotted an error? Tell us.
A life of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.