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For review of Heims's book
William Aspray, interested in von N and Wiener or was it von N and
Turing math dept williams
build one like ours
against big memories
no interest in Newell, Simon, Shaw
Heims has no patience with the reasons people give for their
actions. For example, as someone who would have finished basic
training at the time scheduled for the invasion of Japan, I can
imagine that President Truman had reasons apart from rivalry with the
Russians for approving use of atomic bombs. Perhaps he thought that
relatives of soldiers who died
More questions for Armer:
When was von Neumann letter against purchase of large memory?
plane geometry was a lovely subject, and the new math people were
wrong to kill it.
In an undoubtedly apocryphal story, von Neumann is told that
two trains start 100 miles apart moving towards one another at 40 and
60 miles per hour respectively. A bee flying 80 miles an hour starts
at the same time from one end, flies till it meets a train reverses
its course, meets the other train, reverses again, etc. until it is
crushed in the collision of the trains. How far did the bee fly?
After 30 seconds, von Neumann gives the correct answer - 80 miles.
On being told that some physicist also took 30 seconds, he
indignantly replies, "Don't be silly. No physicist can sum a series
that fast."
Heims's discussion of Wiener's and von Neumann's postwar work
on in the relation of computers and brains misses the fact that
subsequent developments followed a different path than either
envisaged. Wiener emphasized feedback and non-linear but continuous
phenomena, and von Neumann emphasized the architecture of large
reliable systems and the problem of self-reproduction. The direction
that has led to fruitful results in artificial intelligence and
cognitive science was pointed out in 1950 by the British logician
Alan Turing. It is the programming of digital computers to carry out
intellectual processes on the psychological level. Like almost
everyone interested in artificial intelligence until the middle
fifties, von Neumann thought in terms of new kinds of machines rather
than programming digital computers. Had it been otherwise, his
enormous ability and familiarity with mathematical logic might have
enabled him to solve easily problems that are still giving trouble
twenty five years later.
After World War II, Wiener and von Neumann put much study
into the relation between computing and the brain. Wiener emphasized
the non-linear servo-mechanism theory to which he had already made
mathematical contributions, and von Neumann wanted to develop a
general logical theory of automata. Unfortunately, only fragments of
the theory of the theory were developed and these concerned
peripheral issues. While von Neumann was instrumental in promoting
and designing the first American stored program digital computers, he
seemed to think of them primarily for numerical computations in
physics and business. His approach to the brain, like that of almost
all scientists interested in the brain was through machines acting
like nerve nets. He showed how reliable computation could be carried
out by machines made of very unreliable parts, and showed that there
were no difficulties in principal to making machines that could
reproduce themselves. Unfortunately, both of these questions have so
far been of peripheral importance.
Among scientists active before the middle fifies, only Alan
Turing, the British logician and computer scientist responsible for
the mathematical concept of computability in the 1930s and wartime
machines for breaking German ciphers took the view that has dominated
artificial intelligence research since the middle 1950s. In 1950
Turing proposed that the problem wasn't to build special machines but
to program digital computers to carry out intellectual functions.
Von Neumann also missed the applicability of his other
specialty of mathematical logic to representing facts about the world
within a machine.
Heims's portrait of Wiener and von Neumann as people is
unfortunately marred by political bias. Wiener is accepted as a good
guy because he announced his refusal to work on military problems
after World War II, and von Neumann taken as a bad guy because he
worked on nuclear weapons. A mixture of psychology and Marxoid Kline
summary Each of these books tells some history of mathematics
and mathematicians to support a general thesis. The history is
interesting mostly accurate, but I don't believe the theses.
Professor Kline's history of mathematics centers around the
thesis that mathematics has suffered repeated disasters, shocks and
xxx and lacks the certainty that it was once reputed to have.
When one begins the study of mathematics, one is interested
in learning from others how to solve problems. Some people, after
getting good at this, then develop an interest in rigorous reasoning.
They want to develop methods of solving harder problems, and they
want to be able to prove that their new methods are correct.
Eventually they become aware that what their understanding of what
they took for granted about the elementary parts of mathematics does
not have the rigor that they later learned to appreciate. Some of
them even become interested in the "foundations of mathematics".
Forgetting their own attitude as beginners, they often become
pedantic pests and suppose that beginners want to have everything
proved from whatever the new rigorist has come to believe are first
principles.
As it was with the individual, so it was with the development
of mathematics itself. The Babylonians and Egyptians were only
interested in methods of solving problems, and it was left to the
Greeks to develop the rigorous methods of Euclidean plane geometry.
While the higher level parts of Greek geometry became rigorous, at
the bottom vagueness remained. A point was "defined" as that which
has no parts, and the need for having postulates about when one point
on a line is between two others was not noticed until the late
nineteenth century. Minsky:
1. von N. told Tucker that Minsky's thesis topic would eventually
lead to good mathematics.
2. generally encouraging but not interested in neural nets
3. Wiener was so insecure as to be hard to talk to.
Hurd:
1. look at computers and the brain
2. von N. did not express himself about memory size, was for symbolic
assembly programs, consulted on combining symbolic and numerical
computation.
Simon:
1. contact on economics
2. self-generating complexity, hixon
3. warning against brain analogy
4. computers weren't brains
5. chess playing computers, negative to Shannon idea Simon motivated
by counter-reaction
6. started work in 36
7. mcculloch pitts, grey walter, ashy, rashevsky,
8. selfridge and dineen
Samuel:
1. no opinion of checker efforts
2. mainly numerical computation
3. 1024 words was enough
4. Wiener liked to lecture on Samuel's program, wrong and exalted
ideas
5. McCulloch did write some programs but too early to run them