Childhood The Shannon family lived in
Gaylord, Michigan, and Claude was born in a hospital in nearby
Petoskey. Most of the first 16 years of Shannon's life were spent in Gaylord, where he attended public school, graduating from Gaylord High School in 1932. Shannon showed an inclination towards mechanical and electrical subjects. His best subjects were science and mathematics. At home, he constructed such devices as models of planes, a radio-controlled model boat and a barbed-wire
telegraph system to a friend's house a half-mile away. While growing up, he also worked as a messenger for the
Western Union company. Shannon's childhood hero was
Thomas Edison, whom he later learned was a distant cousin. Both Shannon and Edison were descendants of
John Ogden (1609–1682), a colonial leader and an ancestor of many distinguished people.
Logic circuits In 1932, Shannon entered the
University of Michigan, where he was introduced to the work of
George Boole. He graduated in 1936 with two bachelor's degrees: one in electrical engineering and the other in mathematics. In 1936, Shannon began his graduate studies in electrical engineering at the
Massachusetts Institute of Technology (MIT), where he worked on
Vannevar Bush's
differential analyzer, which was an early
analog computer that was composed of electromechanical parts and could solve
differential equations. While studying the complicated
ad hoc circuits of this analyzer, Shannon designed
switching circuits based on
Boole's concepts. In 1937, he wrote his master's degree thesis,
A Symbolic Analysis of Relay and Switching Circuits, Herman Goldstine described it in 1972 as "surely ... one of the most important master's theses ever written ... It helped to change digital circuit design from an art to a science." One of the reviewers of his work commented that "To the best of my knowledge, this is the first application of the methods of symbolic logic to so practical an engineering problem. From the point of view of originality I rate the paper as outstanding." Shannon's master's thesis won the
1939 Alfred Noble Prize. Shannon received his PhD in mathematics from MIT in 1940. However, the thesis went unpublished after Shannon lost interest, but it did contain important results. In addition, Shannon devised a general expression for the distribution of several linked traits in a population after multiple generations under a random mating system, which was original at the time, with the new theorem unworked out by other
population geneticists of the time. In 1940, Shannon became a National Research Fellow at the
Institute for Advanced Study in
Princeton, New Jersey. In Princeton, Shannon had the opportunity to discuss his ideas with influential scientists and mathematicians such as
Hermann Weyl and
John von Neumann, and he also had occasional encounters with
Albert Einstein and
Kurt Gödel. Shannon worked freely across disciplines, and this ability may have contributed to his later development of mathematical information theory.
Wartime research Shannon had worked at
Bell Labs for a few months in the summer of 1937, and returned there to work on
fire-control systems and
cryptography during World War II, under a contract with section D-2 (Control Systems section) of the
National Defense Research Committee (NDRC). Shannon is credited with the invention of
signal-flow graphs, in 1942. He discovered the topological gain formula while investigating the functional operation of an analog computer. For two months early in 1943, Shannon came into contact with the leading British mathematician
Alan Turing. Turing had been posted to Washington to share with the
U.S. Navy's cryptanalytic service the methods used by the
Government Code and Cypher School at
Bletchley Park to break the cyphers used by the
Kriegsmarine U-boats in the north Atlantic Ocean. He was also interested in the encipherment of speech and to this end spent time at Bell Labs. Shannon and Turing met at teatime in the cafeteria. This impressed Shannon, as many of its ideas complemented his own. Shannon and his team developed anti-aircraft systems that tracked enemy missiles and planes, while also determining the paths for intercepting missiles. In 1945, as the war was coming to an end, the NDRC was issuing a summary of technical reports as a last step prior to its eventual closing down. Inside the volume on fire control, a special essay titled
Data Smoothing and Prediction in Fire-Control Systems, coauthored by Shannon,
Ralph Beebe Blackman, and
Hendrik Wade Bode, formally treated the problem of smoothing the data in fire-control by analogy with "the problem of separating a signal from interfering noise in communications systems." In other words, it modeled the problem in terms of
data and
signal processing and thus heralded the coming of the
Information Age. Shannon's work on cryptography was even more closely related to his later publications on
communication theory. At the close of the war, he prepared a classified memorandum for
Bell Telephone Labs entitled "A Mathematical Theory of Cryptography", dated September 1945. A declassified version of this paper was published in 1949 as "
Communication Theory of Secrecy Systems" in the
Bell System Technical Journal. This paper incorporated many of the concepts and mathematical formulations that also appeared in his
A Mathematical Theory of Communication. Shannon said that his wartime insights into communication theory and cryptography developed simultaneously, and that "they were so close together you couldn't separate them". In a footnote near the beginning of the classified report, Shannon announced his intention to "develop these results … in a forthcoming memorandum on the transmission of information." While he was at Bell Labs, Shannon proved that the
cryptographic one-time pad is unbreakable in his classified research that was later published in 1949. The same article also proved that any unbreakable system must have essentially the same characteristics as the one-time pad: the key must be truly random, as large as the plaintext, never reused in whole or part, and kept secret.
Information theory In 1948, the promised memorandum appeared as "A Mathematical Theory of Communication", an article in two parts in the July and October issues of the
Bell System Technical Journal. This work focuses on the problem of how best to encode the message a sender wants to transmit. Shannon developed
information entropy as a measure of the information content in a message, which is a measure of uncertainty reduced by the message. In so doing, he essentially invented the field of
information theory. The book
The Mathematical Theory of Communication and which is concerned with representing a continuous-time signal from a (uniform) discrete set of samples. This theory was essential in enabling telecommunications to move from analog to digital transmissions systems in the 1960s and later. He further wrote a paper in 1956 regarding coding for a noisy channel, which also became a classic paper in the field of information theory. However, also in 1956 he wrote a one-page editorial for the "IRE Transactions on Information Theory" entitled "The Bandwagon" which he began by observing: "Information theory has, in the last few years, become something of a scientific bandwagon" and which he concluded by warning: "Only by maintaining a thoroughly scientific attitude can we achieve real progress in communication theory and consolidate our present position." Claude Shannon's influence has been immense in the field, for example, in a 1973 collection of the key papers in the field of information theory, he was author or coauthor of 12 of the 49 papers cited, while no one else appeared more than three times. Even beyond his original paper in 1948, he is still regarded as the most important post-1948 contributor to the theory. In May 1951,
Mervin Kelly received a request from the director of the
CIA, general
Walter Bedell Smith, regarding Shannon and the need for him, as Shannon was regarded as, based on "the best authority", the "most eminently qualified scientist in the particular field concerned". As a result of the request, Shannon became part of the CIA's Special Cryptologic Advisory Group or SCAG.
Artificial intelligence mouse
Theseus (named after
Theseus from Greek mythology) which he tried to have solve the maze in one of the first experiments in
artificial intelligence Theseus, the mouse In 1950, Shannon designed and built, with the help of his wife, Betty, a learning machine named Theseus. It consisted of a maze on a surface, through which a mechanical mouse could move. Below the surface were sensors (an electromechanical relay circuit) that followed the path of a mechanical mouse through the maze.
Other artificial intelligence work Shannon wrote multiple influential papers on artificial intelligence, such as his 1950 paper titled "Programming a Computer for Playing Chess", and his 1953 paper titled "Computers and Automata". Alongside
John McCarthy, he co-edited a book titled
Automata Studies, which was published in 1956. The categories in the articles within the volume were influenced by Shannon's own subject headings in his 1953 paper. Shannon shared McCarthy's goal of creating a science of intelligent machines, but also held a broader view of viable approaches in automata studies, such as neural nets, Turing machines, cybernetic mechanisms, and symbolic processing by computer.
Later life Shannon developed
Alzheimer's disease and spent the last few years of his life in a
nursing home; he died in 2001, survived by his wife, a son and daughter, and two granddaughters.
Hobbies and inventions , a digital computer trainer designed by Shannon Outside of Shannon's academic pursuits, he was interested in
juggling,
unicycling, and
chess. He also invented many devices, including a
Roman numeral computer called THROBAC, and
juggling machines. He built a device that could solve the
Rubik's Cube puzzle. Shannon designed the
Minivac 601, a
digital computer trainer to teach business people about how computers functioned. It was sold by the
Scientific Development Corp starting in 1961. He is further considered the co-inventor of the first
wearable computer along with
Edward O. Thorp. The device was used to improve the odds when playing
roulette.
Personal life Shannon married
Norma Levor, a wealthy, Jewish, left-wing intellectual in January 1940. The marriage ended in divorce a year later. Levor later married
Ben Barzman. Shannon met his second wife,
Mary Elizabeth Moore (Betty), when she was a numerical analyst at Bell Labs. They were married in 1949. They had three children. Shannon presented himself as
apolitical and an
atheist.
Tributes and legacy There are six statues of Shannon sculpted by
Eugene Daub: one at the
University of Michigan; one at MIT in the
Laboratory for Information and Decision Systems; one in Gaylord, Michigan; one at the
University of California, San Diego; one at Bell Labs; and another at
AT&T Shannon Labs. The statue in Gaylord is located in the Claude Shannon Memorial Park. After the
breakup of the Bell System, the part of Bell Labs that remained with
AT&T Corporation was named Shannon Labs in his honor. In June 1954, Shannon was listed as one of the top 20 most important scientists in America by
Fortune. In 2013, information theory was listed as one of the top 10 revolutionary scientific theories by
Science News. According to
Neil Sloane, an
AT&T Fellow who co-edited Shannon's large collection of papers in 1993, the perspective introduced by Shannon's communication theory (now called "information theory") is the foundation of the
digital revolution, and every device containing a
microprocessor or
microcontroller is a conceptual descendant of Shannon's publication in 1948: "He's one of the great men of the century. Without him, none of the things we know today would exist. The whole digital revolution started with him." The
cryptocurrency unit shannon (a synonym for gwei, one billion
wei) is named after him. Shannon is credited by many as single-handedly creating information theory and for laying the foundations for the
Digital Age. His achievements are considered to be on par with those of
Albert Einstein,
Sir Isaac Newton, and
Charles Darwin.
A Mind at Play, a biography of Shannon written by
Jimmy Soni and Rob Goodman, was published in 2017. They described Shannon as "the most important genius you’ve never heard of, a man whose intellect was on par with
Albert Einstein and
Isaac Newton". Consultant and writer Tom Rutledge, writing for
Boston Review, stated that "Of the computer pioneers who drove the mid-20th-century information technology revolution—an elite men’s club of scholar-engineers who also helped crack Nazi codes and pinpoint missile trajectories—Shannon may have been the most brilliant of them all." Due to his work in multiple fields, Shannon is also regarded as a
polymath. Historian
James Gleick noted the importance of Shannon, stating that "Einstein looms large, and rightly so. But we’re not living in the relativity age, we’re living in the information age. It’s Shannon whose fingerprints are on every electronic device we own, every computer screen we gaze into, every means of digital communication. He’s one of these people who so transform the world that, after the transformation, the old world is forgotten." Gleick further noted that "he created a whole field from scratch, from the brow of
Zeus".
The Bit Player, a feature film about Shannon directed by
Mark Levinson premiered at the
World Science Festival in 2019. Drawn from interviews conducted with Shannon in his house in the 1980s, the film was released on Amazon Prime in August 2020.
Claude, the
large language model developed by artificial intelligence research company
Anthropic, is partially named in honor of Shannon. ==
The Mathematical Theory of Communication==