Claude Elwood Shannon (April 30, 1916 – February 24, 2001) was an American
mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...
,
electrical engineer
Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems that use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...
,
computer scientist
A computer scientist is a scientist who specializes in the academic study of computer science.
Computer scientists typically work on the theoretical side of computation. Although computer scientists can also focus their work and research on ...
,
cryptographer
Cryptography, or cryptology (from "hidden, secret"; and ''graphein'', "to write", or '' -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adversarial behavior. More gen ...
and inventor known as the "father of
information theory
Information theory is the mathematical study of the quantification (science), quantification, Data storage, storage, and telecommunications, communication of information. The field was established and formalized by Claude Shannon in the 1940s, ...
" and the man who laid the foundations of the
Information Age
The Information Age is a historical period that began in the mid-20th century. It is characterized by a rapid shift from traditional industries, as established during the Industrial Revolution, to an economy centered on information technology ...
.
Shannon was the first to describe the use of
Boolean algebra
In mathematics and mathematical logic, Boolean algebra is a branch of algebra. It differs from elementary algebra in two ways. First, the values of the variable (mathematics), variables are the truth values ''true'' and ''false'', usually denot ...
—essential to all
digital electronic
Digital electronics is a field of electronics involving the study of digital signals and the engineering of devices that use or produce them. It deals with the relationship between binary inputs and outputs by passing electrical signals through ...
circuits—and helped found
artificial intelligence
Artificial intelligence (AI) is the capability of computer, computational systems to perform tasks typically associated with human intelligence, such as learning, reasoning, problem-solving, perception, and decision-making. It is a field of re ...
(AI).
Roboticist
Rodney Brooks
Rodney Allen Brooks (born 30 December 1954) is an Australian robotics, roboticist, Fellow of the Australian Academy of Science, author, and robotics entrepreneur, most known for popularizing the behavior based robotics, actionist approach to ro ...
declared Shannon the 20th century engineer who contributed the most to 21st century technologies,
and mathematician
Solomon W. Golomb
Solomon Wolf Golomb ( ; May 30, 1932 – May 1, 2016) was an American mathematician, engineer, and professor of electrical engineering at the University of Southern California, best known for his works on mathematical games. He most notably inven ...
described his intellectual achievement as "one of the greatest of the twentieth century".
At the
University of Michigan
The University of Michigan (U-M, U of M, or Michigan) is a public university, public research university in Ann Arbor, Michigan, United States. Founded in 1817, it is the oldest institution of higher education in the state. The University of Mi ...
, Shannon
dual degree
Joint degrees are academic qualifications awarded through integrated curricula often jointly coordinated and delivered by multiple higher education institutions, sometimes across different countries. Graduates may receive a single qualification ...
d, graduating with a Bachelor of Science in electrical engineering and another in mathematics, both in 1936. A 21-year-old
master's degree
A master's degree (from Latin ) is a postgraduate academic degree awarded by universities or colleges upon completion of a course of study demonstrating mastery or a high-order overview of a specific field of study or area of professional prac ...
student in electrical engineering at
MIT
The Massachusetts Institute of Technology (MIT) is a private research university in Cambridge, Massachusetts, United States. Established in 1861, MIT has played a significant role in the development of many areas of modern technology and sc ...
, his thesis, "
A Symbolic Analysis of Relay and Switching Circuits
''A Symbolic Analysis of Relay and Switching Circuits'' is the title of a master's thesis written by computer science pioneer Claude E. Shannon while attending the Massachusetts Institute of Technology (MIT) in 1937, and then published in 1938. ...
", demonstrated that electrical applications of
Boolean algebra
In mathematics and mathematical logic, Boolean algebra is a branch of algebra. It differs from elementary algebra in two ways. First, the values of the variable (mathematics), variables are the truth values ''true'' and ''false'', usually denot ...
could construct any logical numerical relationship,
thereby establishing the theory behind
digital computing and
digital circuits
Digital electronics is a field of electronics involving the study of digital signals and the engineering of devices that use or produce them. It deals with the relationship between binary inputs and outputs by passing electrical signals through ...
. Called by some the most important master's thesis of all time,
it is the "birth certificate of the digital revolution", and started him in a lifetime of work that led him to win a
Kyoto Prize
The is Japan's highest private award for lifetime achievement in the arts and sciences. It is given not only to those that are top representatives of their own respective fields, but to "those who have contributed significantly to the scientific, ...
in 1985. He graduated from MIT in 1940 with a PhD in mathematics;
his thesis focusing on
genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinians, Augustinian ...
contained important results, while initially going unpublished.
Shannon contributed to the field of
cryptanalysis
Cryptanalysis (from the Greek ''kryptós'', "hidden", and ''analýein'', "to analyze") refers to the process of analyzing information systems in order to understand hidden aspects of the systems. Cryptanalysis is used to breach cryptographic se ...
for national defense of the United States during
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
, including his fundamental work on codebreaking and secure
telecommunications
Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of ...
, writing a
paper
Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, Textile, rags, poaceae, grasses, Feces#Other uses, herbivore dung, or other vegetable sources in water. Once the water is dra ...
which is considered one of the foundational pieces of modern cryptography, with his work described as "a turning point, and marked the closure of classical cryptography and the beginning of modern cryptography".
The work of Shannon was foundational for
symmetric-key cryptography
Symmetric-key algorithms are algorithms for cryptography that use the same Key (cryptography), cryptographic keys for both the encryption of plaintext and the decryption of ciphertext. The keys may be identical, or there may be a simple transforma ...
, including the work of
Horst Feistel
Horst Feistel (January 30, 1915 – November 14, 1990) was a German-American cryptographer who worked on the design of ciphers at IBM, initiating research that culminated in the development of the Data Encryption Standard (DES) in the 1970s. The ...
, the
Data Encryption Standard
The Data Encryption Standard (DES ) is a symmetric-key algorithm for the encryption of digital data. Although its short key length of 56 bits makes it too insecure for modern applications, it has been highly influential in the advancement of cryp ...
(DES), and the
Advanced Encryption Standard
The Advanced Encryption Standard (AES), also known by its original name Rijndael (), is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology (NIST) in 2001.
AES is a variant ...
(AES).
As a result, Shannon has been called the "founding father of modern cryptography".
His 1948 paper "
A Mathematical Theory of Communication
"A Mathematical Theory of Communication" is an article by mathematician Claude E. Shannon published in '' Bell System Technical Journal'' in 1948. It was renamed ''The Mathematical Theory of Communication'' in the 1949 book of the same name, a s ...
" laid the foundations for the field of information theory,
referred to as a "blueprint for the digital era" by electrical engineer
Robert G. Gallager
Robert Gray Gallager (born May 29, 1931) is an American electrical engineer known for his work on information theory and communications networks.
Gallager was elected a member of the National Academy of Engineering (NAE) in 1979 for contributi ...
and "the
Magna Carta
(Medieval Latin for "Great Charter"), sometimes spelled Magna Charta, is a royal charter of rights agreed to by King John of England at Runnymede, near Windsor, on 15 June 1215. First drafted by the Archbishop of Canterbury, Cardin ...
of the Information Age" by ''
Scientific American
''Scientific American'', informally abbreviated ''SciAm'' or sometimes ''SA'', is an American popular science magazine. Many scientists, including Albert Einstein and Nikola Tesla, have contributed articles to it, with more than 150 Nobel Pri ...
''.
Golomb compared Shannon's influence on the digital age to that which "the inventor of the alphabet has had on literature".
Advancements across multiple scientific disciplines utilized Shannon's theory—including the invention of the
compact disc
The compact disc (CD) is a Digital media, digital optical disc data storage format co-developed by Philips and Sony to store and play digital audio recordings. It employs the Compact Disc Digital Audio (CD-DA) standard and was capable of hol ...
, the development of the
Internet
The Internet (or internet) is the Global network, global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a internetworking, network of networks ...
, the commercialization of mobile telephony, and the understanding of
black hole
A black hole is a massive, compact astronomical object so dense that its gravity prevents anything from escaping, even light. Albert Einstein's theory of general relativity predicts that a sufficiently compact mass will form a black hole. Th ...
s. He also formally introduced the term "
bit
The bit is the most basic unit of information in computing and digital communication. The name is a portmanteau of binary digit. The bit represents a logical state with one of two possible values. These values are most commonly represented as ...
",
and was a co-inventor of both
pulse-code modulation
Pulse-code modulation (PCM) is a method used to digitally represent analog signals. It is the standard form of digital audio in computers, compact discs, digital telephony and other digital audio applications. In a PCM stream, the amplitud ...
and the first
wearable computer
A wearable computer, also known as a body-borne computer, is a computing device worn on the body. The definition of 'wearable computer' may be narrow or broad, extending to smartphones or even ordinary wristwatches.
Wearables may be for general ...
.
Shannon made numerous contributions to the field of artificial intelligence,
including co-organizing the 1956
Dartmouth workshop
The Dartmouth Summer Research Project on Artificial Intelligence was a 1956 summer workshop widely consideredKline, Ronald R., "Cybernetics, Automata Studies and the Dartmouth Conference on Artificial Intelligence", ''IEEE Annals of the History ...
considered to be the discipline's founding event,
and papers on the programming of chess computers.
His Theseus machine was the first electrical device to learn by trial and error, being one of the first examples of artificial intelligence.
Biography
Childhood
The Shannon family lived in
Gaylord, Michigan
Gaylord ( ') is a city in the U.S. state of Michigan. It is the county seat of Otsego County, Michigan, Otsego County, and the only city within the county. Gaylord had a population of 4,286 at the 2020 United States census, 2020 census, an incre ...
, and Claude was born in a hospital that was nearby
Petoskey.
His father, Claude Sr. (1862–1934), was a businessman and, for a while, a judge of
probate
In common law jurisdictions, probate is the judicial process whereby a will is "proved" in a court of law and accepted as a valid public document that is the true last testament of the deceased; or whereby, in the absence of a legal will, the e ...
in
Gaylord. His mother, Mabel Wolf Shannon (1880–1945), was a language teacher, who also served as the principal of
Gaylord High School. Claude Sr. was a descendant of
New Jersey settlers, while Mabel was a child of German immigrants.
Shannon's family was active in their Methodist Church during his youth.
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 things. 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
Telegraphy is the long-distance transmission of messages where the sender uses symbolic codes, known to the recipient, rather than a physical exchange of an object bearing the message. Thus flag semaphore is a method of telegraphy, whereas ...
system to a friend's house a half-mile away. While growing up, he also worked as a messenger for the
Western Union
The Western Union Company is an American multinational financial services corporation headquartered in Denver, Denver, Colorado.
Founded in 1851 as the New York and Mississippi Valley Printing Telegraph Company in Rochester, New York, the co ...
company.
Shannon's childhood hero was
Thomas Edison
Thomas Alva Edison (February11, 1847October18, 1931) was an American inventor and businessman. He developed many devices in fields such as electric power generation, mass communication, sound recording, and motion pictures. These inventions, ...
, who he later learned was a distant cousin. Both Shannon and Edison were descendants of
John Ogden John Ogden may refer to:
* John Ogden (colonist) (1609-1682), an American colonial leader
* John Ogden (actor) (died 1732), a British stage actor
* John B. Ogden (1812–?), 19th century Arkansas judge
* John Ogden (academic), co-founder of Fisk Un ...
(1609–1682), a colonial leader and an ancestor of many distinguished people.
Logic circuits
In 1932, Shannon entered the
University of Michigan
The University of Michigan (U-M, U of M, or Michigan) is a public university, public research university in Ann Arbor, Michigan, United States. Founded in 1817, it is the oldest institution of higher education in the state. The University of Mi ...
, where he was introduced to the work of
George Boole
George Boole ( ; 2 November 1815 – 8 December 1864) was a largely self-taught English mathematician, philosopher and logician, most of whose short career was spent as the first professor of mathematics at Queen's College, Cork in Ireland. H ...
. He graduated in 1936 with two
bachelor's degree
A bachelor's degree (from Medieval Latin ''baccalaureus'') or baccalaureate (from Modern Latin ''baccalaureatus'') is an undergraduate degree awarded by colleges and universities upon completion of a course of study lasting three to six years ...
s: one in
electrical engineering
Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems that use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...
and the other in mathematics.
In 1936, Shannon began his graduate studies in
electrical engineering
Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems that use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...
at the
Massachusetts Institute of Technology
The Massachusetts Institute of Technology (MIT) is a Private university, private research university in Cambridge, Massachusetts, United States. Established in 1861, MIT has played a significant role in the development of many areas of moder ...
(MIT), where he worked on
Vannevar Bush
Vannevar Bush ( ; March 11, 1890 – June 28, 1974) was an American engineer, inventor and science administrator, who during World War II, World War II headed the U.S. Office of Scientific Research and Development (OSRD), through which almo ...
's
differential analyzer
The differential analyser is a mechanical analogue computer designed to solve differential equations by integration, using wheel-and-disc mechanisms to perform the integration. It was one of the first advanced computing devices to be used ope ...
, which was an early
analog computer
An analog computer or analogue computer is a type of computation machine (computer) that uses physical phenomena such as Electrical network, electrical, Mechanics, mechanical, or Hydraulics, hydraulic quantities behaving according to the math ...
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
A master's degree (from Latin ) is a postgraduate academic degree awarded by universities or colleges upon completion of a course of study demonstrating mastery or a high-order overview of a specific field of study or area of professional prac ...
thesis, ''
A Symbolic Analysis of Relay and Switching Circuits
''A Symbolic Analysis of Relay and Switching Circuits'' is the title of a master's thesis written by computer science pioneer Claude E. Shannon while attending the Massachusetts Institute of Technology (MIT) in 1937, and then published in 1938. ...
,''
with a paper from this thesis published in 1938.
A revolutionary work for
switching circuit theory
Switching circuit theory is the mathematical study of the properties of networks of idealized switches. Such networks may be strictly combinational logic, in which their output state is only a function of the present state of their inputs; or may ...
, Shannon diagramed switching circuits that could implement the essential operators of
Boolean algebra
In mathematics and mathematical logic, Boolean algebra is a branch of algebra. It differs from elementary algebra in two ways. First, the values of the variable (mathematics), variables are the truth values ''true'' and ''false'', usually denot ...
. Then he proved that his switching circuits could be used to simplify the arrangement of the
electromechanical
Electromechanics combine processes and procedures drawn from electrical engineering and mechanical engineering. Electromechanics focus on the interaction of electrical and mechanical systems as a whole and how the two systems interact with each ...
relay
A relay
Electromechanical relay schematic showing a control coil, four pairs of normally open and one pair of normally closed contacts
An automotive-style miniature relay with the dust cover taken off
A relay is an electrically operated switc ...
s that were used during that time in
telephone call routing switches. Next, he expanded this concept, proving that these circuits could solve all problems that Boolean algebra could solve. In the last chapter, he presented diagrams of several circuits, including a digital 4-bit full adder.
His work differed significantly from the work of previous engineers such as
Akira Nakashima
Akira Nakashima (中嶋 章 or 中島 章, also written as ''Nakashima Akira'', ''Nakasima Akira'' or ''Nakajima Akira'', 5 January 1908 – 29 October 1970) was a Japanese electrical engineer of the NEC.
He got a bachelor's degree in electri ...
, who still relied on the existent circuit theory of the time and took a grounded approach.
Shannon's idea were more abstract and relied on mathematics, thereby breaking new ground with his work, with his approach dominating modern-day electrical engineering.
Using electrical switches to implement logic is the fundamental concept that underlies all
electronic digital computers. Shannon's work became the foundation of
digital circuit
In theoretical computer science, a circuit is a model of computation in which input values proceed through a sequence of gates, each of which computes a function. Circuits of this kind provide a generalization of Boolean circuits and a mathematica ...
design, as it became widely known in the electrical engineering community during and after
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
. The theoretical rigor of Shannon's work superseded the ''ad hoc'' methods that had prevailed previously.
Howard Gardner
Howard Earl Gardner (born July 11, 1943) is an American developmental psychologist and the John H. and Elisabeth A. Hobbs Research Professor of Cognition and Education at Harvard University. He was a founding member of Harvard Project Zero in 1967 ...
hailed Shannon's thesis "possibly the most important, and also the most famous, master's thesis of the century."
Herman Goldstine
Herman Heine Goldstine (September 13, 1913 – June 16, 2004) was a mathematician and computer scientist, who worked as the director of the IAS machine at the Institute for Advanced Study and helped to develop ENIAC, the first of the modern ...
described it 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.
Vannevar Bush had suggested that Shannon should work on his dissertation at the
Cold Spring Harbor Laboratory
Cold Spring Harbor Laboratory (CSHL) is a private, non-profit institution with research programs focusing on cancer, neuroscience, botany, genomics, and quantitative biology. It is located in Laurel Hollow, New York, in Nassau County, on ...
, in order to develop a mathematical formulation for
Mendelian
Mendelian inheritance (also known as Mendelism) is a type of biological inheritance following the principles originally proposed by Gregor Mendel in 1865 and 1866, re-discovered in 1900 by Hugo de Vries and Carl Correns, and later popularized ...
genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinians, Augustinian ...
. This research resulted in Shannon's PhD thesis, called ''An Algebra for Theoretical Genetics''. However, the thesis went unpublished after Shannon lost interest, but it did contain important results.
Notably, he was one of the first to apply an algebraic framework to study theoretical population genetics. 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
Population genetics is a subfield of genetics that deals with genetic differences within and among populations, and is a part of evolutionary biology. Studies in this branch of biology examine such phenomena as adaptation, speciation, and popula ...
of the time.
In 1940, Shannon became a National Research Fellow at the
Institute for Advanced Study
The Institute for Advanced Study (IAS) is an independent center for theoretical research and intellectual inquiry located in Princeton, New Jersey. It has served as the academic home of internationally preeminent scholars, including Albert Ein ...
in
Princeton, New Jersey
The Municipality of Princeton is a Borough (New Jersey), borough in Mercer County, New Jersey, United States. It was established on January 1, 2013, through the consolidation of the Borough of Princeton, New Jersey, Borough of Princeton and Pri ...
. In Princeton, Shannon had the opportunity to discuss his ideas with influential scientists and
mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...
s such as
Hermann Weyl
Hermann Klaus Hugo Weyl (; ; 9 November 1885 – 8 December 1955) was a German mathematician, theoretical physicist, logician and philosopher. Although much of his working life was spent in Zürich, Switzerland, and then Princeton, New Jersey, ...
and
John von Neumann
John von Neumann ( ; ; December 28, 1903 – February 8, 1957) was a Hungarian and American mathematician, physicist, computer scientist and engineer. Von Neumann had perhaps the widest coverage of any mathematician of his time, in ...
, and he also had occasional encounters with
Albert Einstein
Albert Einstein (14 March 187918 April 1955) was a German-born theoretical physicist who is best known for developing the theory of relativity. Einstein also made important contributions to quantum mechanics. His mass–energy equivalence f ...
and
Kurt Gödel
Kurt Friedrich Gödel ( ; ; April 28, 1906 – January 14, 1978) was a logician, mathematician, and philosopher. Considered along with Aristotle and Gottlob Frege to be one of the most significant logicians in history, Gödel profoundly ...
. 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
Nokia Bell Labs, commonly referred to as ''Bell Labs'', is an American industrial research and development company owned by Finnish technology company Nokia. With headquarters located in Murray Hill, New Jersey, Murray Hill, New Jersey, the compa ...
for a few months in the summer of 1937, and returned there to work on
fire-control system
A fire-control system (FCS) is a number of components working together, usually a gun data computer, a director and radar, which is designed to assist a ranged weapon system to target, track, and hit a target. It performs the same task as a hum ...
s and
cryptography
Cryptography, or cryptology (from "hidden, secret"; and ''graphein'', "to write", or ''-logy, -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of Adversary (cryptography), ...
during
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
, under a contract with section D-2 (Control Systems section) of the
National Defense Research Committee
The National Defense Research Committee (NDRC) was an organization created "to coordinate, supervise, and conduct scientific research on the problems underlying the development, production, and use of mechanisms and devices of warfare" in the U ...
(NDRC).
Shannon is credited with the invention of
signal-flow graph
A signal-flow graph or signal-flowgraph (SFG), invented by Claude Shannon, but often called a Mason graph after Samuel Jefferson Mason who coined the term, is a specialized Flow graph (mathematics), flow graph, a directed graph in which nodes rep ...
s, 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
Alan Mathison Turing (; 23 June 1912 – 7 June 1954) was an English mathematician, computer scientist, logician, cryptanalyst, philosopher and theoretical biologist. He was highly influential in the development of theoretical computer ...
. Turing had been posted to Washington to share with the
U.S. Navy
The United States Navy (USN) is the maritime service branch of the United States Department of Defense. It is the world's most powerful navy with the largest displacement, at 4.5 million tons in 2021. It has the world's largest aircraft ...
's cryptanalytic service the methods used by the
Government Code and Cypher School
The Government Code and Cypher School (GC&CS) was a British signals intelligence agency set up in 1919. During the First World War, the British Army and Royal Navy had separate signals intelligence agencies, MI1b and NID25 (initially known as R ...
at
Bletchley Park
Bletchley Park is an English country house and Bletchley Park estate, estate in Bletchley, Milton Keynes (Buckinghamshire), that became the principal centre of Allies of World War II, Allied World War II cryptography, code-breaking during the S ...
to break the cyphers used by the ''
Kriegsmarine
The (, ) was the navy of Nazi Germany from 1935 to 1945. It superseded the Imperial German Navy of the German Empire (1871–1918) and the inter-war (1919–1935) of the Weimar Republic. The was one of three official military branch, branche ...
''
U-boat
U-boats are Submarine#Military, naval submarines operated by Germany, including during the World War I, First and Second World Wars. The term is an Anglicization#Loanwords, anglicized form of the German word , a shortening of (), though the G ...
s in the north
Atlantic Ocean
The Atlantic Ocean is the second largest of the world's five borders of the oceans, oceanic divisions, with an area of about . It covers approximately 17% of Earth#Surface, Earth's surface and about 24% of its water surface area. During the ...
.
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.
Turing showed Shannon his 1936 paper that defined what is now known as the "
universal Turing machine
In computer science, a universal Turing machine (UTM) is a Turing machine capable of computing any computable sequence, as described by Alan Turing in his seminal paper "On Computable Numbers, with an Application to the Entscheidungsproblem". Co ...
". 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
Hendrik Wade Bode ( , ;Van Valkenburg, M. E. University of Illinois at Urbana-Champaign, "In memoriam: Hendrik W. Bode (1905-1982)", IEEE Transactions on Automatic Control, Vol. AC-29, No 3., March 1984, pp. 193–194. Quote: "Something should be ...
, 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
Data ( , ) are a collection of discrete or continuous values that convey information, describing the quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted for ...
and
signal processing
Signal processing is an electrical engineering subfield that focuses on analyzing, modifying and synthesizing ''signals'', such as audio signal processing, sound, image processing, images, Scalar potential, potential fields, Seismic tomograph ...
and thus heralded the coming of the
Information Age
The Information Age is a historical period that began in the mid-20th century. It is characterized by a rapid shift from traditional industries, as established during the Industrial Revolution, to an economy centered on information technology ...
.
Shannon's work on cryptography was even more closely related to his later publications on
communication theory
Communication theory is a proposed description of communication phenomena, the relationships among them, a storyline describing these relationships, and an argument for these three elements. Communication theory provides a way of talking about a ...
. 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
"Communication Theory of Secrecy Systems" is a paper published in 1949 by Claude Shannon discussing cryptography from the viewpoint of information theory
Information theory is the mathematical study of the quantification (science), quantifica ...
" in the ''
Bell System Technical Journal
The ''Bell Labs Technical Journal'' was the in-house scientific journal for scientists of Bell Labs, published yearly by the IEEE society.
The journal was originally established as ''The Bell System Technical Journal'' (BSTJ) in New York by the Am ...
''. This paper incorporated many of the concepts and mathematical formulations that also appeared in his ''
A Mathematical Theory of Communication
"A Mathematical Theory of Communication" is an article by mathematician Claude E. Shannon published in '' Bell System Technical Journal'' in 1948. It was renamed ''The Mathematical Theory of Communication'' in the 1949 book of the same name, a s ...
''. 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
Cryptography, or cryptology (from "hidden, secret"; and ''graphein'', "to write", or '' -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adversarial behavior. More gen ...
one-time pad
The one-time pad (OTP) is an encryption technique that cannot be Cryptanalysis, cracked in cryptography. It requires the use of a single-use pre-shared key that is larger than or equal to the size of the message being sent. In this technique, ...
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
In information theory, the entropy of a random variable quantifies the average level of uncertainty or information associated with the variable's potential states or possible outcomes. This measures the expected amount of information needed ...
as a measure of the
information
Information is an Abstraction, abstract concept that refers to something which has the power Communication, to inform. At the most fundamental level, it pertains to the Interpretation (philosophy), interpretation (perhaps Interpretation (log ...
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
Information theory is the mathematical study of the quantification (science), quantification, Data storage, storage, and telecommunications, communication of information. The field was established and formalized by Claude Shannon in the 1940s, ...
.
The book ''The Mathematical Theory of Communication''
reprints Shannon's 1948 article and
Warren Weaver
Warren Weaver (July 17, 1894 – November 24, 1978) was an American scientist, mathematician, and science administrator. He is widely recognized as one of the pioneers of machine translation and as an important figure in creating support for scie ...
's popularization of it, which is accessible to the non-specialist. Weaver pointed out that the word "information" in communication theory is not related to what you do say, but to what you could say. That is, information is a measure of one's freedom of choice when one selects a message. Shannon's concepts were also popularized, subject to his own proofreading, in
John Robinson Pierce
John Robinson Pierce (March 27, 1910 – April 2, 2002), was an American engineer and author. He did extensive work concerning radio communication, microwave technology, computer music, psychoacoustics, and science fiction. Additionally to hi ...
's ''Symbols, Signals, and Noise''.
Information theory's fundamental contribution to
natural language processing
Natural language processing (NLP) is a subfield of computer science and especially artificial intelligence. It is primarily concerned with providing computers with the ability to process data encoded in natural language and is thus closely related ...
and
computational linguistics
Computational linguistics is an interdisciplinary field concerned with the computational modelling of natural language, as well as the study of appropriate computational approaches to linguistic questions. In general, computational linguistics ...
was further established in 1951, in his article "Prediction and Entropy of Printed English", showing upper and lower bounds of entropy on the statistics of English – giving a statistical foundation to language analysis. In addition, he proved that treating
space
Space is a three-dimensional continuum containing positions and directions. In classical physics, physical space is often conceived in three linear dimensions. Modern physicists usually consider it, with time, to be part of a boundless ...
as the 27th letter of the alphabet actually lowers uncertainty in written language, providing a clear quantifiable link between cultural practice and probabilistic cognition.
Another notable paper published in 1949 is "
Communication Theory of Secrecy Systems
"Communication Theory of Secrecy Systems" is a paper published in 1949 by Claude Shannon discussing cryptography from the viewpoint of information theory
Information theory is the mathematical study of the quantification (science), quantifica ...
", a declassified version of his wartime work on the mathematical theory of cryptography, in which he proved that all theoretically unbreakable cyphers must have the same requirements as the one-time pad. He is credited with the introduction of
sampling theorem
Sampling may refer to:
*Sampling (signal processing), converting a continuous signal into a discrete signal
*Sample (graphics), Sampling (graphics), converting continuous colors into discrete color components
*Sampling (music), the reuse of a soun ...
, which he had derived as early as 1940, 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
The Central Intelligence Agency (CIA; ) is a civilian foreign intelligence service of the federal government of the United States tasked with advancing national security through collecting and analyzing intelligence from around the world and ...
, general
Walter Bedell Smith
General (United States), General Walter Bedell "Beetle" Smith (5 October 1895 – 9 August 1961) was a senior officer (armed forces), officer of the United States Army who served as General Dwight D. Eisenhower's chief of staff at Allied Forc ...
, 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.
In his time at Bell Labs, he also co-developed
pulse-code modulation
Pulse-code modulation (PCM) is a method used to digitally represent analog signals. It is the standard form of digital audio in computers, compact discs, digital telephony and other digital audio applications. In a PCM stream, the amplitud ...
alongside
Bernard M. Oliver, and
John R. Pierce
John Robinson Pierce (March 27, 1910 – April 2, 2002), was an American engineer and author. He did extensive work concerning radio communication, microwave technology, computer music, psychoacoustics, and science fiction. Additionally to ...
.
Artificial Intelligence
In 1950, Shannon designed and built, with the help of his wife, 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 that followed the path of a mechanical mouse through the maze. After much trial and error, this device would learn the shortest path through the maze, and direct the mechanical mouse through the maze. The pattern of the maze could be changed at will.
Mazin Gilbert
Mazin Gilbert is an electrical engineer with Google. He earned his Ph.D. (1991) and BEng (1987) in Electrical and Electronic Engineering from Liverpool University, and an MBA for Executives, from the Wharton Business School (2009).
Gilbert was na ...
stated that Theseus "inspired the whole field of AI. This random trial and error is the foundation of artificial intelligence."
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 John McCarthy may refer to:
Government
* John George MacCarthy (1829–1892), Member of Parliament for Mallow constituency, 1874–1880
* John McCarthy (Irish politician) (1862–1893), Member of Parliament for the Mid Tipperary constituency, ...
, 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.
Shannon co-organized and participated in the
Dartmouth workshop
The Dartmouth Summer Research Project on Artificial Intelligence was a 1956 summer workshop widely consideredKline, Ronald R., "Cybernetics, Automata Studies and the Dartmouth Conference on Artificial Intelligence", ''IEEE Annals of the History ...
of 1956, alongside John McCarthy,
Marvin Minsky
Marvin Lee Minsky (August 9, 1927 – January 24, 2016) was an American cognitive scientist, cognitive and computer scientist concerned largely with research in artificial intelligence (AI). He co-founded the Massachusetts Institute of Technology ...
and
Nathaniel Rochester
Nathaniel Rochester (February 21, 1752 – May 17, 1831) was an American Revolutionary War soldier and land speculator, most noted for founding the settlement which would become Rochester, New York.
Early life
Nathaniel Rochester was the ...
, and which is considered the founding event of the field of artificial intelligence.
Teaching at MIT
In 1956 Shannon joined the MIT faculty, holding an endowed chair. He worked in the Research Laboratory of Electronics (RLE). He continued to serve on the MIT faculty until 1978.
Later life
Shannon developed
Alzheimer's disease
Alzheimer's disease (AD) is a neurodegenerative disease and the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems wit ...
and spent the last few years of his life in a
nursing home
A nursing home is a facility for the residential care of older people, senior citizens, or disabled people. Nursing homes may also be referred to as care homes, skilled nursing facilities (SNF), or long-term care facilities. Often, these terms ...
; he died in 2001, survived by his wife, a son and daughter, and two granddaughters.
Hobbies and inventions

Outside of Shannon's academic pursuits, he was interested in
juggling
Juggling is a physical skill, performed by a juggler, involving the manipulation of objects for recreation, entertainment, art or sport. The most recognizable form of juggling is toss juggling. Juggling can be the manipulation of one object o ...
,
unicycling
A unicycle is a vehicle that touches the ground with only one wheel. The most common variation has a bicycle frame, frame with a bicycle saddle, saddle, and has a human-powered vehicle, pedal-driven direct-drive mechanism, direct-drive. A two spe ...
, and
chess
Chess is a board game for two players. It is an abstract strategy game that involves Perfect information, no hidden information and no elements of game of chance, chance. It is played on a square chessboard, board consisting of 64 squares arran ...
. He also invented many devices, including a
Roman numeral
Roman numerals are a numeral system that originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. Numbers are written with combinations of letters from the Latin alphabet, ea ...
computer called THROBAC, and
juggling machines. He built a device that could solve the
Rubik's Cube puzzle.
Shannon also invented flame-throwing
trumpet
The trumpet is a brass instrument commonly used in classical and jazz musical ensemble, ensembles. The trumpet group ranges from the piccolo trumpet—with the highest Register (music), register in the brass family—to the bass trumpet, pitche ...
s, rocket-powered
frisbee
A frisbee (pronounced ), also called a flying disc or simply a disc, is a gliding toy or sporting item generally made of injection-molded plastic and roughly in diameter with a pronounced lip. It is used recreationally and competitively for ...
s, and plastic foam
shoe
A shoe is an item of footwear intended to protect and comfort the human foot. Though the human foot can adapt to varied terrains and climate conditions, it is vulnerable, and shoes provide protection. Form was originally tied to function, but ...
s for navigating a lake, and which to an observer, would appear as if Shannon was walking on water.
Shannon designed the
Minivac 601, a
digital computer
A computer is a machine that can be programmed to automatically carry out sequences of arithmetic or logical operations (''computation''). Modern digital electronic computers can perform generic sets of operations known as ''programs'', wh ...
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
A wearable computer, also known as a body-borne computer, is a computing device worn on the body. The definition of 'wearable computer' may be narrow or broad, extending to smartphones or even ordinary wristwatches.
Wearables may be for general ...
along with
Edward O. Thorp
Edward Oakley Thorp (born August 14, 1932) is an American mathematics professor, author, hedge fund manager, and blackjack researcher. He pioneered the modern applications of probability theory, including the harnessing of very small correlatio ...
.
The device was used to improve the odds when playing
roulette
Roulette (named after the French language, French word meaning "little wheel") is a casino game which was likely developed from the Italy, Italian game Biribi. In the game, a player may choose to place a bet on a single number, various grouping ...
.
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
Ben Barzman (October 12, 1910 – December 15, 1989) was a Canadian journalist, screenwriter, and novelist, blacklisted during the McCarthy Era and known best for his screenplays for the movies '' Back to Bataan'' (1945), ''El Cid'' (1961), and ...
.
Shannon met his second wife,
Mary Elizabeth Moore (Betty), when she was a numerical analyst at Bell Labs. They were married in 1949.
Betty assisted Claude in building some of his most famous inventions. They had three children.
Shannon presented himself as
apolitical
Apoliticism is apathy or antipathy towards all political affiliations. A person may be described as apolitical if they are uninterested or uninvolved in politics. Being apolitical can also refer to situations in which people take an unbiased p ...
and an
atheist
Atheism, in the broadest sense, is an absence of belief in the existence of deities. Less broadly, atheism is a rejection of the belief that any deities exist. In an even narrower sense, atheism is specifically the position that there no ...
.
Tributes and legacy
There are six statues of Shannon sculpted by
Eugene Daub
Eugene Daub (born November 13, 1942) is an American contemporary figure sculptor, best known for his portraits and figurative monument sculpture created in the classic heroic style. His sculptures reside in three of the nation's state capitals an ...
: one at the
University of Michigan
The University of Michigan (U-M, U of M, or Michigan) is a public university, public research university in Ann Arbor, Michigan, United States. Founded in 1817, it is the oldest institution of higher education in the state. The University of Mi ...
; one at MIT in the
Laboratory for Information and Decision Systems; one in Gaylord, Michigan; one at the
University of California, San Diego
The University of California, San Diego (UC San Diego in communications material, formerly and colloquially UCSD) is a public university, public Land-grant university, land-grant research university in San Diego, California, United States. Es ...
; 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 Bell System held a virtual monopoly over telephony infrastructure in the United States since the early 20th century until January 8, 1982.
This divestiture of the Bell Operating Companies was initiated in 1974 when the United States Departme ...
, the part of Bell Labs that remained with
AT&T Corporation
AT&T Corporation, an abbreviation for its former name, the American Telephone and Telegraph Company, was an American telecommunications company that provided voice, video, data, and Internet telecommunications and professional services to busi ...
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
Fortune may refer to:
General
* Fortuna or Fortune, the Roman goddess of luck
* Luck
* Wealth
* Fate
* Fortune, a prediction made in fortune-telling
* Fortune, in a fortune cookie
Arts and entertainment Film and television
* ''The Fortune'' (19 ...
''.
In 2013, information theory was listed as one of the top 10 revolutionary scientific theories by ''
Science News
''Science News'' (''SN'') is an American monthly magazine devoted to articles about new scientific and technical developments, typically gleaned from recent scientific and technical journals. The periodical has been described as having a scop ...
''.
According to
Neil Sloane
__NOTOC__
Neil James Alexander Sloane FLSW (born October 10, 1939) is a British-American mathematician. His major contributions are in the fields of combinatorics, error-correcting codes, and sphere packing. Sloane is best known for being the cre ...
, 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
The Information Age is a History by period, historical period that began in the mid-20th century. It is characterized by a rapid shift from traditional industries, as established during the Industrial Revolution, to an economy centered on info ...
, 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 (unit), shannon (a synonym for gwei) is named after him.
Shannon is credited by many as single-handedly creating information theory and for laying the foundations for the Information Age, Digital Age.
His achievements are considered to be on par with those of
Albert Einstein
Albert Einstein (14 March 187918 April 1955) was a German-born theoretical physicist who is best known for developing the theory of relativity. Einstein also made important contributions to quantum mechanics. His mass–energy equivalence f ...
, Isaac Newton, Sir Isaac Newton, and Charles Darwin.
The artificial intelligence large language model family Claude (language model) was named in Shannon's honor.
''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
Albert Einstein (14 March 187918 April 1955) was a German-born theoretical physicist who is best known for developing the theory of relativity. Einstein also made important contributions to quantum mechanics. His mass–energy equivalence f ...
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."
Electrical engineer Robert G. Gallager, Robert Gallager stated about Shannon that "He had this amazing clarity of vision. Einstein had it, too – this ability to take on a complicated problem and find the right way to look at it, so that things become very simple."
In an obituary by Neil Sloane and Robert Calderbank, they stated that "Shannon must rank near the top of the list of major figures of twentieth century science". 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".
On April 30, 2016, Shannon was honored with a Google Doodle to celebrate his life on what would have been his 100th birthday.
''The Bit Player'', a feature film about Shannon directed by Mark Levinson (film director), 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.
''The Mathematical Theory of Communication''
Weaver's Contribution
Shannon's ''The Mathematical Theory of Communication,''
begins with an interpretation of his own work by
Warren Weaver
Warren Weaver (July 17, 1894 – November 24, 1978) was an American scientist, mathematician, and science administrator. He is widely recognized as one of the pioneers of machine translation and as an important figure in creating support for scie ...
. Although Shannon's entire work is about communication itself, Warren Weaver communicated his ideas in such a way that those not acclimated to complex theory and mathematics could comprehend the fundamental laws he put forth. The coupling of their unique communicational abilities and ideas generated the Shannon–Weaver model, Shannon-Weaver model, although the mathematical and theoretical underpinnings emanate entirely from Shannon's work after Weaver's introduction. For the layman, Weaver's introduction better communicates ''The Mathematical Theory of Communication'',
but Shannon's subsequent logic, mathematics, and expressive precision was responsible for defining the problem itself.
Other work
Shannon's mouse
"Theseus", created in 1950, was a mechanical mouse controlled by an electromechanical relay circuit that enabled it to move around a maze, labyrinth of 25 squares.
The maze configuration was flexible and it could be modified arbitrarily by rearranging movable partitions.
The mouse was designed to search through the corridors until it found the target. Having travelled through the maze, the mouse could then be placed anywhere it had been before, and because of its prior experience it could go directly to the target. If placed in unfamiliar territory, it was programmed to search until it reached a known location and then it would proceed to the target, adding the new knowledge to its memory and learning new behavior.
Shannon's mouse appears to have been the first artificial learning device of its kind.
Shannon's estimate for the complexity of chess
In 1949 Shannon completed a paper (published in March 1950) which estimates the Game complexity, game-tree complexity of
chess
Chess is a board game for two players. It is an abstract strategy game that involves Perfect information, no hidden information and no elements of game of chance, chance. It is played on a square chessboard, board consisting of 64 squares arran ...
, which is approximately 10
120. This number is now often referred to as the "Shannon number", and is still regarded today as an accurate estimate of the game's complexity. The number is often cited as one of the barriers to Solving chess, solving the game of chess using an exhaustive analysis (i.e. Brute-force search, brute force analysis).
Shannon's computer chess program
On March 9, 1949, Shannon presented a paper called "Programming a Computer for playing Chess". The paper was presented at the National Institute for Radio Engineers Convention in New York. He described how to program a computer to play chess based on position scoring and move selection. He proposed basic strategies for restricting the number of possibilities to be considered in a game of chess. In March 1950 it was published in ''Philosophical Magazine'', and is considered one of the first articles published on the topic of programming a computer for playing chess, and using a computer to solve the game.
In 1950, Shannon wrote an article titled "A Chess-Playing Machine", which was published in ''
Scientific American
''Scientific American'', informally abbreviated ''SciAm'' or sometimes ''SA'', is an American popular science magazine. Many scientists, including Albert Einstein and Nikola Tesla, have contributed articles to it, with more than 150 Nobel Pri ...
.'' Both papers have had immense influence and laid the foundations for future chess programs.
His process for having the computer decide on which move to make was a minimax procedure, based on an evaluation function of a given chess position. Shannon gave a rough example of an evaluation function in which the value of the black position was subtracted from that of the white position. ''Material'' was counted according to the usual chess piece relative value (1 point for a pawn, 3 points for a knight or bishop, 5 points for a rook, and 9 points for a queen). He considered some positional factors, subtracting ½ point for each doubled pawn, backward pawn, and isolated pawn; ''mobility (chess), mobility'' was incorporated by adding 0.1 point for each legal move available.
Shannon's maxim
Shannon formulated a version of Kerckhoffs's principle, Kerckhoffs' principle as "The enemy knows the system". In this form it is known as "Shannon's maxim".
Miscellaneous
Shannon also contributed to combinatorics and detection theory.
His 1948 paper introduced many tools used in combinatorics. He did work on detection theory in 1944, with his work being one of the earliest expositions of the “matched filter” principle.
He was known as a successful investor who gave lectures on investing. A report from ''Barron's'' on August 11, 1986, detailed the recent performance of 1,026 mutual funds, and Shannon achieved a higher return than 1,025 of them. Comparing the portfolio of Shannon from the late 1950s to 1986, to Warren Buffett's of 1965 to 1995, Shannon had a return of about 28% percent, compared to 27% for Buffett. One such method of Shannon's was labeled Shannon's demon, which was to form a portfolio of equal parts cash and a stock, and rebalance regularly to take advantage of the stock's randomly jittering price movements.
Shannon reportedly long thought of publishing about investing, but ultimately did not, despite giving multiple lectures.
He was one of the first investors to download stock prices, and a snapshot of his portfolio in 1981 was found to be $582,717.50, translating to $1.5 million in 2015, excluding another one of his stocks.
Commemorations
Shannon centenary

The Shannon centenary, 2016, marked the life and influence of Claude Elwood Shannon on the hundredth anniversary of his birth on April 30, 1916. It was inspired in part by the Alan Turing Year. An ad hoc committee of the IEEE Information Theory Society including Christina Fragouli, Rüdiger Urbanke, Michelle Effros, Lav Varshney and Sergio Verdú, coordinated worldwide events. The initiative was announced in the History Panel at the 2015 IEEE Information Theory Workshop Jerusalem and the IEEE Information Theory Society newsletter.
A detailed listing of confirmed events was available on the website of the IEEE Information Theory Society.
Some of the activities included:
*
Bell Labs
Nokia Bell Labs, commonly referred to as ''Bell Labs'', is an American industrial research and development company owned by Finnish technology company Nokia. With headquarters located in Murray Hill, New Jersey, Murray Hill, New Jersey, the compa ...
hosted the First Shannon Conference on the Future of the Information Age on April 28–29, 2016, in Murray Hill, New Jersey, to celebrate Claude Shannon and the continued impact of his legacy on society. The event includes keynote speeches by global luminaries and visionaries of the information age who will explore the impact of information theory on society and our digital future, informal recollections, and leading technical presentations on subsequent related work in other areas such as bioinformatics, economic systems, and social networks. There is also a student competition
*
Bell Labs
Nokia Bell Labs, commonly referred to as ''Bell Labs'', is an American industrial research and development company owned by Finnish technology company Nokia. With headquarters located in Murray Hill, New Jersey, Murray Hill, New Jersey, the compa ...
launched
Web exhibiton April 30, 2016, chronicling Shannon's hiring at Bell Labs (under an NDRC contract with US Government), his subsequent work there from 1942 through 1957, and details of Mathematics Department. The exhibit also displayed bios of colleagues and managers during his tenure, as well as original versions of some of the technical memoranda which subsequently became well known in published form.
* The Republic of Macedonia issued a commemorative stamp. A United States Postal Service, USPS commemorative stamp is being proposed, with an active petition.
* A documentary on Claude Shannon and on the impact of information theory, The Bit Player, was produced by Sergio Verdú and Mark Levinson (film director), Mark Levinson.
* A trans-Atlantic celebration of both George Boole's bicentenary and Claude Shannon's centenary that is being led by University College Cork and the Massachusetts Institute of Technology. A first event was a workshop in Cork, When Boole Meets Shannon, and will continue with exhibits at the Museum of Science (Boston), Boston Museum of Science and at the MIT Museum.
* Many organizations around the world are holding observance events, including the Boston Museum of Science, the Heinz-Nixdorf Museum, the Institute for Advanced Study, Technische Universität Berlin, University of South Australia (UniSA), Unicamp (Universidade Estadual de Campinas), University of Toronto, Chinese University of Hong Kong, Cairo University, Telecom ParisTech, National Technical University of Athens, Indian Institute of Science, Indian Institute of Technology Bombay, Indian Institute of Technology Kanpur, Nanyang Technological University of Singapore, University of Maryland, University of Illinois at Chicago, École Polytechnique Federale de Lausanne, The Pennsylvania State University (Penn State), University of California Los Angeles, Massachusetts Institute of Technology, Chongqing University of Posts and Telecommunications, and University of Illinois at Urbana-Champaign.
* A logo that appears on this page was crowdsourced on Crowdspring.
* The Math Encounters presentation of May 4, 2016, at the National Museum of Mathematics in New York, titled ''Saving Face: Information Tricks for Love and Life'', focused on Shannon's work in information theory. A video recording and other material are available.
Awards and honors list
The Claude E. Shannon Award was established in his honor; he was also its first recipient, in 1973.
* Alfred Noble Prize of the American Society of Civil Engineers, 1939
* Stuart Ballantine Medal of the Franklin Institute, 1955
* Member of the American Academy of Arts and Sciences, 1957
* Harvey Prize, the Technion of Haifa, Israel, 1972
*Alfred Noble Prize, 1939 (award of civil engineering societies in the US)
* National Medal of Science, 1966, presented by President Lyndon B. Johnson
*
Kyoto Prize
The is Japan's highest private award for lifetime achievement in the arts and sciences. It is given not only to those that are top representatives of their own respective fields, but to "those who have contributed significantly to the scientific, ...
, 1985
*Morris Liebmann Memorial Prize of the Institute of Radio Engineers, 1949
* United States National Academy of Sciences, 1956
* IEEE Medal of Honor, Medal of Honor of the Institute of Electrical and Electronics Engineers, 1966
* Golden Plate Award of the Academy of Achievement, American Academy of Achievement, 1967
* Royal Netherlands Academy of Arts and Sciences (KNAW), foreign member, 1975
* Member of the American Philosophical Society, 1983
* Member of the Royal Irish Academy, 1985
* Eduard Rhein Award, Basic Research Award, Eduard Rhein Foundation, Germany, 1991
* Marconi Prize, Marconi Society Lifetime Achievement Award, 2000
* William Donner, Donnor Professor of Science, MIT, 1958–1979
Selected works
* Claude E. Shannon: ''
A Symbolic Analysis of Relay and Switching Circuits
''A Symbolic Analysis of Relay and Switching Circuits'' is the title of a master's thesis written by computer science pioneer Claude E. Shannon while attending the Massachusetts Institute of Technology (MIT) in 1937, and then published in 1938. ...
'', master's thesis, MIT, 1937.
* Claude E. Shannon: "A Mathematical Theory of Communication", ''Bell System Technical Journal'', Vol. 27, pp. 379–423, 623–656, 1948
abstract.
* Claude E. Shannon and Warren Weaver: ''The Mathematical Theory of Communication.'' The University of Illinois Press, Urbana, Illinois, 1949.
*
Neil Sloane
__NOTOC__
Neil James Alexander Sloane FLSW (born October 10, 1939) is a British-American mathematician. His major contributions are in the fields of combinatorics, error-correcting codes, and sphere packing. Sloane is best known for being the cre ...
editor (1993
''Claude Shannon: Collected Works'' IEEE Press
See also
*Entropy power inequality
*Error-correcting codes with feedback
*List of pioneers in computer science
*Models of communication
*n-gram
*Noisy channel coding theorem
*Nyquist–Shannon sampling theorem
*One-time pad
*Product cipher
*Pulse-code modulation
*Rate distortion theory
*Sampling (signal processing), Sampling
*Shannon capacity (disambiguation), Shannon capacity
*Shannon entropy
*Shannon index
*Shannon multigraph
*Shannon security
*Shannon switching game
*Shannon–Fano coding
*Shannon–Hartley law
*Shannon–Hartley theorem
*Shannon's expansion
*Shannon's source coding theorem
*Shannon–Weaver model, Shannon-Weaver model of communication
*Whittaker–Shannon interpolation formula
References
Further reading
* Rethnakaran Pulikkoonattu — Eric W. Weisstein: Mathworld biography of Shannon, Claude Elwood (1916–2001
Shannon, Claude Elwood (1916–2001) – from Eric Weisstein's World of Scientific Biography* Claude E. Shannon: ''Programming a Computer for Playing Chess'', Philosophical Magazine, Ser.7, Vol. 41, No. 314, March 1950. (Available online under ''External links'' below)
* David Levy: ''Computer Gamesmanship: Elements of Intelligent Game Design'', Simon & Schuster, 1983.
* Mindell, David A., "Automation's Finest Hour: Bell Labs and Automatic Control in World War II", IEEE Control Systems, December 1995, pp. 72–80.
* Poundstone, William, ''Fortune's Formula'', Hill & Wang, 2005,
* James Gleick, Gleick, James, ''The Information: A History, a Theory, a Flood, The Information: A History, A Theory, A Flood'', Pantheon, 2011,
* Jimmy Soni and Rob Goodman, ''A Mind at Play, A Mind at Play: How Claude Shannon Invented the Information Age'', Simon and Schuster, 2017,
* Nahin, Paul J., ''The Logician and the Engineer: How George Boole and Claude Shannon Created the Information Age'', Princeton University Press, 2013,
* Everett M. Rogers, '' Claude Shannon's Cryptography Research During World War II and the Mathematical Theory of Communication'', 1994 Proceedings of IEEE International Carnahan Conference on Security Technology, pp. 1–5, 1994
Claude Shannon's cryptography research during World War II and the mathematical theory of communication
External links
*
Guide to the Claude Elwood Shannon papersat the Library of Congress
*
Claude Elwood Shannon (1916–2001)at the ''Notices of the American Mathematical Society''
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