''A Symbolic Analysis of Relay and Switching Circuits'' is the title of a master's thesis written by

computer science Computer science is the study of computation, information, and automation. Computer science spans Theoretical computer science, theoretical disciplines (such as algorithms, theory of computation, and information theory) to Applied science, ...

pioneer Claude E. Shannon while attending 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) in 1937, and then published in 1938. In his thesis, Shannon, a dual degree graduate of the

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, proved that

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 be used to simplify the arrangement of the relays that were the building blocks of the electromechanical

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s of the day. He went on to prove that it should also be possible to use arrangements of relays to solve Boolean algebra problems. His thesis laid the foundations for all 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 ...

. The utilization of the binary properties of electrical switches to perform logic functions is the basic concept that underlies all electronic digital computer designs. Shannon's thesis became the foundation of practical

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 when it became widely known among the

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 ...

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 ...

. At the time, the methods employed to design logic circuits (for example, contemporary

Konrad Zuse Konrad Ernst Otto Zuse (; ; 22 June 1910 – 18 December 1995) was a German civil engineer, List of pioneers in computer science, pioneering computer scientist, inventor and businessman. His greatest achievement was the world's first programm ...

's Z1) were ''

ad hoc ''Ad hoc'' is a List of Latin phrases, Latin phrase meaning literally for this. In English language, English, it typically signifies a solution designed for a specific purpose, problem, or task rather than a Generalization, generalized solution ...

'' in nature and lacked the theoretical discipline that Shannon's paper supplied to later projects. Shannon's work also differered significantly in its approach and theoretical framework compared to the work of Akira Nakashima. Whereas Shannon's approach and framework was abstract and based on mathematics, Nakashima tried to extend the existent circuit theory of the time to deal with relay circuits, and was reluctant to accept the mathematical and abstract model, favoring a grounded approach. Shannon's ideas broke new ground, with his abstract and modern approach dominating modern-day electrical engineering. The paper is commonly regarded as the most important master's thesis ever due to its insights and influence. Pioneering computer scientist Herman Goldstine described Shannon's thesis 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." In 1985, psychologist

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 ...

called his thesis "possibly the most important, and also the most famous, master's thesis of the century". The paper won the 1939 Alfred Noble Prize. A version of the paper was published in the 1938 issue of the '' Transactions of the American Institute of Electrical Engineers.''

References

External links

Full text at MIT
{{DEFAULTSORT:Symbolic Analysis Of Relay And Switching Circuits Computer science papers Information theory Applied mathematics 1937 in science 1937 documents Claude Shannon Theses