Lotfi Zadeh

Azerbaijani-born American mathematician and electrical engineer at the University of California, Berkeley, from 1959, the founder of fuzzy logicfuzzy logic, n.: A kind of logic that allows degrees of truth, so a statement like 'the room is warm' can be 70 percent true, which helps machines handle vague everyday categories.. Raised in Iran and educated at the University of Tehran, MIT and Columbia University, he first worked in systems theory, co-writing a standard text on the state-space approach to linear systems (1963). His paper 'Fuzzy Sets' (1965) replaced the all-or-nothing membership of classical sets with degrees of membership between 0 and 1, and in the 1970s he built on it linguistic variables, fuzzy if–then rules and possibility theory. Initially derided by many engineers and statisticians, fuzzy methods spread in control systems, notably in Japanese trains, cameras and appliances from the late 1980s. In the early 1990s he promoted soft computingsoft computing, n.: A group of computing methods, including fuzzy logic, neural networks and evolutionary algorithms, that accept imprecise, approximate answers in exchange for being practical on messy real-world problems. as the combination of fuzzy logic, neural networks and evolutionary methods. Honors include the IEEE Medal of Honor (1995).