John von Neumann

John Von Neumann
John Von Neumann, 1932

born: Dec 28, 1903 Budapest
died: Feb 8, 1957 Washington, D.C.

We can all think clearly, more or less, some of the time, but von Neumann’s clarity of thought was orders of magnitude greater than that of most of us, all the time. For von Neumann it seemed to be impossible to be unclear in thought or in expression.
(Paul Halmos)

Keeping up with him was all but impossible. The feeling was you were on a tricycle chasing a racing car.
(Israel Halperin)

Father of game theory. Mathematical contributions to set theory, ergodic theory, operator theory. Contributions to quantum mechanics, logic, war, computing theory and practice, economics. A modern legend.
Von Neumann was the oldest of three children of a banker, and his speed of learning new ideas and of solving problems stood out early. At 6, he could divide two 8-digit numbers in his head; by 8 he had mastered calculus; by 12 he was at the graduate level in mathematics. He could memorize pages on sight. At 17, his father tried to convince him to become something more financially practical than a mathematician, and von Neumann agreed to study chemistry as well. He arranged to study chemistry in Berlin and then Zurich and mathematics in Budapest. In 1926, at 23, he received a degree in chemical engineering in Zurich and a Ph.D. in mathematics in Budapest. From the start, mathematics provided well enough for him, and he never had to resort to the chemistry.

For the next three years, von Neumann worked mainly in the new field of operator theory in mathematics and on applying it to the new field of quantum theory in physics. His first book, published in 1932, was on quantum mechanics. In 1930, von Neumann visited Princeton for a year and then became a professor there. In 1933, the Institute for Advanced Study was formed, and he became one of the 6 full-time people in the School of Mathematics (Einstein was one of the others).

World War II drastically changed von Neumann’s areas of interest. Until 1940 he had been a great pure mathematician and had made a number of important theoretical contributions in physics. During and after the war, he became one of the best applied mathematicians. He also had a superb grasp of practicalities, and, when some of the best engineers in the world were at Los Alamos trying to decide how to bring the atomic fuel together quickly enough to create an explosion the (A bomb), this mathematician came up with the workable answer — implosion. He even had time to found the area of game theory, “one of the major scientific contributions of the first half of the 20th century.”

During the last part of the war he became involved with the development of computing machines and made several fundamental contributions. It was his idea to store the program (the sequence of instructions) in the machine as simply another kind of electronic data. Until then, in order to reprogram a computer a person had to physically rewire it. Computers which perform their operations sequentially are called “von Neumann machines” as opposed to recent types which can perform several operations at once using “parallel processing.” He, together with Stan Ulam, developed the Monte Carlo technique, a commonly used means of simulating complex situations in science and business.

After the war, von Neumann continued his work with computers, and was generally very active in government service. He received numerous awards, was president of the American Mathematical Society and was a member of the Atomic Energy Commission. He died in 1957 of cancer. A good friend, Wigner, wrote; “When von Neumann realized he was incurably ill, his logic forced him to realize he would cease to exist, and hence cease to have thoughts. It was heartbreaking to watch the frustration of his mind, when all hope was gone, in its struggle with the fate which appeared to him unavoidable but unacceptable.”

Any one of several of his contributions would have been enough to earn him a firm place in history. Von Neumann will be remembered as one of the greatest minds of this century.

Von Neumann really was a legend in his own time, and there are a number of stories about him.

John Von Neumann
John Von Neumann, 1950’s

His driving (in)ability is a part of this legend. He reported one accident this way: “I was proceeding down the road. The trees on the right were passing me in orderly fashion at 60 miles per hour. Suddenly one of them stepped in my path.”

“He was especially pleased with and proud of his facility with numbers. When his electronic computer was ready for its first preliminary test, someone suggested a relatively simple problem involving powers of 2. (Something like, what is the smallest power of 2 with the property that its decimal digit 4th from the right is 7?). The machine and Johnny started at the same time, and Johnny finished first.”

“It is often said that modern mathematics is so vast that no one can know more than a tiny fraction of it. Someone once asked von Neumann how much of mathematics he himself knew. Von Neumann went into one of his characteristic thinking trances. After a moment he had an answer. ‘Twenty-eight percent.'”

(Click JvN for a good longer biography.)

Condensed from “The Legend of John von Neumann” by P. Halmos, American Mathematical Monthly, April, 1973, pages 382-394, and “The Legacy of John von Neumann” by Barry Cipra, SIAM News, Sept., 1988, p. 28, 22-23.

Last Updated September 22, 2022