>
> > It may have come to the attention of some list readers that Claude
Shannon
> > has recently died. Perhaps some of our colleagues from MIT/Bell Labs may
> > like to say a few words in the way of an obituary? The "Mathematical
Theory
> > of Communication" has surely had considerable influence in the broad
area
> > of auditory science, and the concept of information entropy will surely
> > continue to be an important theoretical and practical tool in future
> > developments.
>
>
> Here is an informative memorial that appeared in the NY Times recently:
>
> Claude Shannon, Mathematician, Dies at 84
>
> February 27, 2001
>
> By GEORGE JOHNSON
>
> Dr. Claude Elwood Shannon, the American mathematician and computer
> scientist whose theories laid the groundwork for the electronic
> communications networks that now lace the earth, died on Saturday
> in Medford, Mass., after a long fight with Alzheimer's disease. He
> was 84.
>
> Understanding, before almost anyone, the power that springs from
> encoding information in a simple language of 1's and 0's, Dr.
> Shannon as a young man wrote two papers that remain monuments in
> the fields of computer science and information theory.
>
> "Shannon was the person who saw that the binary digit was the
> fundamental element in all of communication," said Dr. Robert G.
> Gallager, a professor of electrical engineering who worked with Dr.
> Shannon at the Massachusetts Institute of Technology. "That was
> really his discovery, and from it the whole communications
> revolution has sprung."
>
> Dr. Shannon's later work on chess- playing machines and an
> electronic mouse that could run a maze helped create the field of
> artificial intelligence, the effort to make machines that think.
> And his ability to combine abstract thinking with a practical
> approach he had a penchant for building machines inspired a
> generation of computer scientists.
>
> Dr. Marvin Minsky of M.I.T., who as a young theorist worked
> closely with Dr. Shannon, was struck by his enthusiasm and
> enterprise. "Whatever came up, he engaged it with joy, and he
> attacked it with some surprising resource which might be some new
> kind of technical concept or a hammer and saw with some scraps of
> wood," Dr. Minsky said. "For him, the harder a problem might seem,
> the better the chance to find something new."
>
> Born in Petoskey, Mich., on April 30, 1916, Claude Elwood Shannon
> got a bachelor's degree in mathematics and electrical engineering
> from the University of Michigan in 1936. He got both a master's
> degree in electrical engineering and his Ph.D. in mathematics from
> M.I.T. in 1940.
>
> While at M.I.T., he worked with Dr. Vannevar Bush on one of the
> early calculating machines, the "differential analyzer," which used
> a precisely honed system of shafts, gears, wheels and disks to
> solve equations in calculus.
>
> Though analog computers like this turned out to be little more
> than footnotes in the history of the computer, Dr. Shannon quickly
> made his mark with digital electronics, a considerably more
> influential idea.
>
> In what has been described as one of the most important master's
> theses ever written, he showed how Boolean logic, in which problems
> can be solved by manipulating just two symbols, 1 and 0, could be
> carried out automatically with electrical switching circuits. The
> symbol 1 could be represented by a switch that was turned on; 0
> would be a switch that was turned off.
>
> The thesis, "A Symbolic Analysis of Relay and Switching Circuits,"
> was largely motivated by the telephone industry's need to find a
> mathematical language to describe the behavior of the increasingly
> complex switching circuits that were replacing human operators. But
> the implications of the paper were far more broad, laying out a
> basic idea on which all modern computers are built.
>
> George Boole, the 19th-century British mathematician who invented
> the two-symbol logic, grandiosely called his system "The Laws of
> Thought." The idea was not lost on Dr. Shannon, who realized early
> on that, as he once put it, a computer is "a lot more than an
> adding machine." The binary digits could be used to represent
> words, sounds, images perhaps even ideas.
>
> The year after graduating from M.I.T., Dr. Shannon took a job at
> AT&T Bell Laboratories in New Jersey, where he became known for
> keeping to himself by day and riding his unicycle down the halls at
> night.
>
> "Many of us brought our lunches to work and played mathematical
> blackboard games," said a former colleague, Dr. David Slepian.
> "Claude rarely came. He worked with his door closed, mostly. But if
> you went in, he would be very patient and help you along. He could
> grasp a problem in zero time. He really was quite a genius. He's
> the only person I know whom I'd apply that word to."
>
> In 1948, Dr. Shannon published his masterpiece, "A Mathematical
> Theory of Communication," giving birth to the science called
> information theory. The motivation again was practical: how to
> transmit messages while keeping them from becoming garbled by
> noise.
>
> To analyze this problem properly, he realized, he had to come up
> with a precise definition of information, a dauntingly slippery
> concept. The information content of a message, he proposed, has
> nothing to do with its content but simply with the number of 1's
> and 0's that it takes to transmit it.
>
> This was a jarring notion to a generation of engineers who were
> accustomed to thinking of communication in terms of sending
> electromagnetic waveforms down a wire. "Nobody had come close to
> this idea before," Dr. Gallager said. "This was not something
> somebody else would have done for a very long time."
>
> The overarching lesson was that the nature of the message did not
> matter it could be numbers, words, music, video. Ultimately it
> was all just 1's and 0's.
>
> Today, when gigabytes of movie trailers, Napster files and e-mail
> messages course through the same wires as telephone calls, the idea
> seems almost elemental. But it has its roots in Dr. Shannon's
> paper, which may contain the first published occurrence of the word
> "bit."
>
> Dr. Shannon also showed that if enough extra bits were added to a
> message, to help correct for errors, it could tunnel through the
> noisiest channel, arriving unscathed at the end. This insight has
> been developed over the decades into sophisticated error-correction
> codes that ensure the integrity of the data on which society
> interacts.
>
> In later years, his ideas spread beyond the fields of
> communications engineering and computer science, taking root in
> cryptography, the mathematics of probability and even investment
> theory. In biology, it has become second nature to think of DNA
> replication and hormonal signaling in terms of information.
>
> And more than one English graduate student has written papers
> trying to apply information theory to literature the kind of
> phenomenon that later caused Dr. Shannon to complain of what he
> called a "bandwagon effect."
>
> "Information theory has perhaps ballooned to an importance beyond
> its actual accomplishments," he lamented.
>
> After he moved to M.I.T. in 1958, and beyond his retirement two
> decades later, he pursued a diversity of interests a mathematical
> theory of juggling, an analog computer programmed to beat roulette,
> a system for playing the stock market using probability theory.
>
> He is survived by his wife, Mary Elizabeth Moore Shannon; a son,
> Andrew Moore Shannon; a daughter, Margarita Shannon; a sister,
> Catherine S. Kay; and two granddaughters.
>
> In the last years of his life, Alzheimer's disease began to set
> in. "Something inside him was getting lost," Dr. Minsky said. "Yet
> none of us miss him the way you'd expect for the image of that
> great stream of ideas still persists in everyone his mind ever
> touched."
>
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