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John von Neumann's Dangerous
Game
Von Neumann was a key member of
the Manhattan Project team. Members of this gifted scientific gathering
often relied on his mathematical judgment and eventually put him in charge
of the mathematical calculations upon which all their theories depended.
Later, as the director of the Atomic Energy Commission and an influential
member of the ICBM Committee, he ended up a key policy-maker in the fields
of nuclear power, nuclear weapons, and intercontinental ballistic weaponry.
Von Neumann not only used his scientific expertise to hasten and accelerate
the development of nuclear weapons and computer-guided missiles, but counseled
military and political leaders to think about using these new American
inventions against the USSR in a "preventive war." In an article published
shortly after he died, von Neumann was quoted as saying: "If you say why
not bomb them tomorrow, I say, why not today. If you say at five o'clock,
I say why not one o'clock" (Blair, 1957, p. 96).
His contributions to the science
of calculation in the late forties and early fifties were preceded by even
earlier theoretical work that led to the notion of mechanical computation.
In the 1940's, von Neumann learned about an Army project called ENIAC that
was soon to produce a device that would be capable of performing mathematical
calculations at phenomenal speeds. He was one of the principal participants
in both of the lines of thought that converged into the construction of
ENIAC: mathematical logic and ballistics. John von Neumann's role in the
invention of mechanical computation, however, began nearly twenty years
before the ENIAC project.
Von Neumann first established himself
by offering models and explanations of quantum mechanics. He attempted
to explain away the probabilistic elements that Heisenberg introduced into
the understanding of what occurs on the sub-atomic level. He later developed
this preliminary work into Mathematical Foundations of Quantum Mechanics
(1955). Although he never found a complete alternative, it was totally
unacceptable to von Neumann that we could know where an electron might
be at any given moment only in statistical terms. In an attempt to describe
human motives and behaviors in mathematical and logical terms, von Neumann
formulated — and later codified in Theory of Games and Economic Behavior
(1944) — the discipline of game theory. He was driven to create this
discipline out of frustration at the success of Gödel's Theorem, which
problematized the ideal of a consistent and complete set theory, a project
towards which von Neumann had been working with Hilbert. Gödel's Theorem,
like Heisenberg's Principle, represented another telling defeat for strict
determinism. Even so, when humans were involved — as in game theory applied
to economic strategies — von Neumann treated all the elements of a system
as if they could be described through formal logic. His mathematical method
seemed driven by deeper impulses than the sheer power of logic. For him,
the struggle between chance and determinism seemed like an elemental duel
between good and evil. Von Neumann's commitment to logic and mathematics
formed a religious faith wherein science and math transcend time and space
(Heims, pp. 141-162). From that perspective he helped formulate a principle
that has had powerful consequences and many followers.
Von Neumann was particularly interested
in mathematical questions involving turbulence. He was also engaged in
new mathematical methods for modeling complex phenomena like global weather
patterns and the passage of radiation through matter. Future progress in
these fields was severely limited by the human inability to process the
enormous number of consequent calculations or the results of the most interesting
equations. By the 1940's, von Neumann's expertise in the mathematics of
hydrodynamic turbulence and the management of very large calculations took
on unexpected importance; these two specialties were particularly applicable
to the dynamics of explosions and implosions. The designers of the first
fission bomb knew that mathematical problems in both areas had to be solved
before any of the elegant equations of quantum physics could be transformed
into the fireball of a nuclear detonation. As von Neumann already suspected,
the mathematical work involved in designing nuclear and thermonuclear weapons
created an overwhelming amount of calculations.
The War Department's desire for
raw calculating power led von Neumann to travel to Los Alamos in 1943 to
work on the problems of unleashing and harnessing nuclear energy. His contribution
is one that made it possible to create the bombs dropped on Hiroshima and
Nagasaki. Due to his history of fleeing anti-Semitism, it is likely that
his motives for working on the atom bomb were political. At the same time,
he was driven by an equally deep, personal, and even more persistent struggle
for certitude. The predominant characteristic of von Neumann's mathematical
approach was his desire to describe nature in the terms of strict logical
determinism untainted by incompleteness or uncertainty. At Los Alamos,
he faced a particularly difficult problem for which he attempted to develop
a way of simulating atomic events. His solution has had momentous fallout.
When any sufficiently large nuclear
explosion occurs within a container, unless the radioactive material is
properly contained and the timing of triggering explosions perfect, neutrons
stream out of one side of the container. This leak causes an asymmetrical,
much weaker, and more unpredictable blast. In order to make the most potent
blast possible, a series of complex events must be modeled so that the
radioactive material explodes symmetrically. This research appears under
the hygienic guise of solving the "neutron diffusion problem." Until 1943,
when von Neumann and Stanley Ulam worked on the neutron diffusion problem,
there were essentially only two sorts of modeling employed by scientists
and mathematicians to describe complex events: deterministic methods (which
are essentially applied mathematics) and variations on stochastic techniques
(which were known simply as simulation).
To get around the apparently inevitable
incorporation of the random, von Neumann devised a third kind of simulation
called the "Monte Carlo" in homage to the games of luck he enjoyed in the
gambling capital of Europe. He held that random elements in simulations
were unacceptable, a form of contamination tantamount to cheating at cards.
Indeed, his aversion to stochastic modeling and his appreciation of rule-based
games is at the heart of his epistemology. In the Monte Carlo simulation,
Von Neumann devised a non-stochastic formula for approximating the stochastic
operators in non-trivial simulations. Essentially, he had found a deterministic
way to model random events. At the same time, he had rigged the game in
the house's favor. When the Monte Carlo simulation worked, it suggested
not only that we could describe nature without relying on randomness or
chance, but that nature itself was deterministic.
Von Neumann's obsession with how
Heisenberg introduced the element of randomness into science's view of
the universe at its most atomic level — in the orbit of an electron around
a nucleus — was further articulated in game theory as an attempt to further
model human motives and actions in carefully circumscribed arenas. If,
he reasoned, one could simulate and express fully all human actions in
formal rational terms, one could eliminate the random from the quantum
world. Von Neumann's game theory essentially created an infinite matrix
upon which all possible actions by potential actors were mapped. By correlating
the choices of each actor, potential outcomes could be determined with
formal certainty.
Following his work with simulation,
von Neumann proposed the prototypical architecture of the computer. His
work, The Computer and The Brain (1958), clarified what he and others
had done prior to the War in computational design. Contemporaneously, von
Neumann applied what he had learned about eliminating chance to describing
the human mind. Von Neumann outlined an entire programmatic for the science
previously contemplated by Alan Turing; what we now know as artificial
intelligence. In the simple coupling of von Neumann's title — The Computer
and the Brain — he proposed a dual metaphor: the computer as brain
and the brain as computer. In truth the book is only partially devoted
to designing computational technologies. The second half outlines a mechanical
view of individual neurons and how they transmit information. This claim
is premised entirely on what is called cellular automata, the assumption
that neurons are binary (like the "logical switches" von Neumann proposed
as the basis for some of the first giant computers including ENIAC, EDVAC,
MANIAC, and JONIAC and the "gates" proposed by Turing for his Universal
Machine). Von Neumann was moving from a metaphor founded on pure conviction
— the nerve as a binary switch — to embrace a model that has enjoyed prominence
ever since.
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