Lotfi Aliasker Zadeh

Lotfi Aliasker Zadeh (/ˈzɑːdeɪ/; Azerbaijani: Lütfi Rəhim oğlu Ələsgərzadə; Persian: لطفی علی‌عسگرزاده‎; February 4, 1921 – September 6, 2017) was a mathematician, computer scientist, electrical engineer, artificial intelligence researcher and professor emeritus of computer science at the University of California, Berkeley.

Zadeh was best known for proposing fuzzy mathematics consisting of these fuzzy-related concepts: fuzzy sets, fuzzy logic,fuzzy algorithms, fuzzy semantics, fuzzy languages, fuzzy control, fuzzy systems, fuzzy probabilities, fuzzy events, and fuzzy information.

Zadeh was a founding member of the Eurasian Academy.

Zadeh was born in Baku, Azerbaijan SSR, as Lotfi Aliaskerzadeh, to Rahim Aleskerzade, an Iranian Azerbaijani journalist from Ardabil on assignment from Iran, and Fanya Korenman, a Russian Jewish pediatrician from Odessa and an Iranian citizen.The Soviet government at this time courted foreign correspondents, and the family lived well while in Baku.Zadeh attended elementary school for three years there, which he said "had a significant and long-lasting influence on my thinking and my way of looking at things."

In 1931, when Zadeh was ten years old, his family moved to Tehran in Iran, his father's homeland. Zadeh was enrolled in Alborz College, which was a Presbyterian missionary school, where he was educated for the next eight years, and where he met his future wife, Fay. Zadeh says that he was "deeply influenced" by the "extremely decent, fine, honest and helpful" missionaries from the United States who ran the college. "To me they represented the best that you could find in the United States – people from the Midwest with strong roots. They were really 'Good Samaritans' – willing to give of themselves for the benefit of others. So this kind of attitude influenced me deeply. It also instilled in me a deep desire to live in the United States." During this time, Zadeh was awarded several patents.

Despite being more fluent in Russian than in Persian, Zadeh sat for the national university exams and placed third in the entire country. As a student, he ranked first in his class in his first two years. In 1942, he graduated from the University of Tehran with a degree in electrical engineering, one of only three students in that field to graduate that year, due to the turmoil created by World War II, when the United States, Britain and the Soviet Union invaded Iran, whose ruler, Reza Shah, was pro-German. Over 30,000 American soldiers were based there, and Zadeh worked with his father, who did business with them as a contractor for hardware and building materials.

In 1943, Zadeh decided to emigrate to the United States, and traveled to Philadelphia by way of Cairo after months of delay waiting for the proper papers or for the right ship to appear. He arrived in mid-1944, and entered the Massachusetts Institute of Technology (MIT) as a graduate student later that year. While in the United States, he changed his name to Lotfi Asker Zadeh.

He received an MS degree in electrical engineering from MIT in 1946, and then applied to Columbia University, as his parents had settled in New York City. Columbia admitted him as a doctoral student, and offered him an instructorship as well. He received his Ph.D. in electrical engineering from Columbia in 1949, and became an assistant professor the next year.

Zadeh taught for ten years at Columbia, was promoted to Full Professor in 1957, and taught at the University of California, Berkeley from 1959 on. He published his seminal work on fuzzy sets in 1965, in which he detailed the mathematics of fuzzy set theory. In 1973 he proposed his theory of fuzzy logic.

Zadeh was called "quick to shrug off nationalism, insisting there are much deeper issues in life", and was quoted as saying in an interview: "The question really isn't whether I'm American, Russian, Iranian, Azerbaijani, or anything else. I've been shaped by all these people and cultures and I feel quite comfortable among all of them." He noted in the same interview: "Obstinacy and tenacity. Not being afraid to get embroiled in controversy. That's very much a Turkish tradition. That's part of my character, too. I can be very stubborn. That's probably been beneficial for the development of Fuzzy Logic." He described himself as "an American, mathematically oriented, electrical engineer of Iranian descent, born in Russia."

Zadeh was married to Fay Zadeh and had two children, Stella Zadeh and Norman Zada.

Zadeh died in his home in Berkeley, California, on September 6, 2017, at the age of 96. He is buried in the first Alley of Honor in Baku, Azerbaijan, the city in which he was born. His funeral was well attended by "highly respected people", including the president of Azerbaijan. A month previous to his death, the University of Tehran had released an erroneous report that Zadeh had died, but withdrew it several days later.

According to Google Scholar, as of October 2019, Zadeh's work has been cited about 230,000 times in scholarly works, with the 1965 Fuzzy sets paper receiving more than 100,000 citations.

Fuzzy sets and systems

Zadeh, in his theory of fuzzy sets, proposed using a membership function (with a range covering the interval [0,1]) operating on the domain of all possible values.He proposed new operations for the calculus of logic and showed that fuzzy logic was a generalisation of classical and Boolean logic. He also proposed fuzzy numbers as a special case of fuzzy sets, as well as the corresponding rules for consistent mathematical operations (fuzzy arithmetic).

Other contributions

Zadeh is also credited, along with John R. Ragazzini, in 1952, with having pioneered the development of the z-transform method in discrete time signal processing and analysis. These methods are now standard in digital signal processing, digital control, and other discrete-time systems used in industry and research. He was an editor of the International Journal of Computational Cognition.

Zadeh's most recent work included computing with words and perceptions.His recent papers include From Search Engines to Question-Answering Systems—The Role of Fuzzy Logic, Progress in Informatics, No. 1, 1–3, 2005; and Toward a Generalized Theory of Uncertainty (GTU)—An Outline, Information Sciences, Elsevier, Vol. 172, 1–40, 2005.

• 1965. "Fuzzy sets". Information and Control. 1965; 8: 338–353.
• 1965. "Fuzzy sets and systems". In: Fox J, editor. System Theory. Brooklyn, NY: Polytechnic Press, 1965: 29–39.
• 1972. "A fuzzy-set-theoretical interpretation of linguistic hedges". Journal of Cybernetics 1972; 2: 4–34.
• 1973. "Outline of a new approach to the analysis of complex systems and decision processes". IEEE Trans. Systems, Man and Cybernetics, 1973; 3: 28–44.
• 1974. "Fuzzy logic and its application to approximate reasoning". In: Information Processing 74, Proc. IFIP Congr. 1974 (3), pp. 591–594.
• 1975. "Fuzzy logic and approximate reasoning". Synthese, 1975; 30: 407–428.
• 1975. "Calculus of fuzzy restrictions". In: Zadeh LA, Fu KS, Tanaka K, Shimura M, editors. Fuzzy Sets and their Applications to Cognitive and Decision Processes. New York: Academic Press, 1975: 1–39.
• 1975. "The concept of a linguistic variable and its application to approximate reasoning", I-III, Information Sciences 8 (1975) 199–251, 301–357; 9 (1976) 43–80.
• 2002. "From computing with numbers to computing with words — from manipulation ofmeasurements to manipulation of perceptions".International Journal of Applied Math and Computer Science, pp. 307–324, vol. 12, no. 3, 2002.
• 2012. Computing With Words. Principal Concepts and Ideas. Berlin: Springer, 2012.

A complete list of publications is available here.

Zadeh was a Fellow of the Institute of Electrical and Electronics Engineers, the American Academy of Arts and Sciences, the Association for Computing Machinery, the Association for the Advancement of Artificial Intelligence and the International Fuzzy Systems Association, and a member of the National Academy of Engineering. He was also a member of the Academies of Science of Azerbaijan, Bulgaria, Finland, Korea and Poland, and of the International Academy of Systems Studies in Moscow. He received 24 honorary doctorates.

Awards received by Zadeh include, among many others:

• IEEE Education Medal; 1973
• Eringen Medal; 1976
• IEEE Richard W. Hamming Medal, for "seminal contributions to information science and systems, including the conceptualization of fuzzy sets"; 1992
• American Society of Mechanical Engineers Rufus Oldenburger Medal; 1993.
• Honorary Professorship from the Azerbaijan State Oil Academy; 1993
• IEEE Medal of Honor, for "pioneering development of fuzzy logic and its many diverse applications"; 1995
• American Automatic Control Council's Richard E. Bellman Control Heritage Award; 1998.
• ACM Allen Newell Award; 2001
• Outstanding Contribution Award, Web Intelligence Consortium (WIC), Halifax, Canada, 2003.
• Wall of Fame, Heinz Nixdorf MuseumsForum (HNF), Paderborn, Germany, 2004.
• V. Kaufmann Prize and Gold Medal, International Association for Fuzzy-Set Management and Economy (SIGEF), Barcelona, Spain, Nov. 15, 2004.
• J. Keith Brimacombe IPMM Award in recognition of his development of fuzzy set theory and fuzzy logic, 2005.
• Benjamin Franklin Medal in Electrical Engineering from The Franklin Institute in Philadelphia, for inventing and developing the field of "fuzzy logic"; 2009
• Induction into the IEEE Intelligent Systems' AI's Hall of Fame, 2011, "for his work on soft computing, fuzzy logic, and neural-net theory".
• BBVA Foundation Frontiers of Knowledge Award in the category of Information and Communication Technologies (ICT), Spain, 2012.
• Honorary Doctor of the Obuda University (Budapest, Hungary)
• Golden Goose Award, for Fuzzy Logic; 2017

In 2014, the IEEE Systems, Man, and Cybernetics Society established the "Lotfi A. Zadeh Pioneer Award", which is given "To honor a person or persons with outstanding and pioneering contributions to academic and/or industrial research in systems science and engineering, human-machine systems, and/or cybernetics."The award is funding from a $100,000 donation from Zadeh's son, Norm Zadeh, which is administered by the IEEE. Nominees must have "pioneered and developed innovative research, executed in either academe or industry, and has resulted in major scientific advances that are widely recognized in systems science and engineering, human-machine systems, and/or cybernetics. Contributions must have been made at least 15 years prior to the award date."

In February 2019, ADA University in Baku, Azerbaijan presented the first "Lotfi Zadeh Scholarships", which honor the academic success of undergraduate students in the university's School of IT and Engineering. Winners of the scholarship receive a complete tuition waiver for the semester or semester-equivalent in which they achieved a 4.0 average.