Lotfi Zadeh, the computer scientist who developed “fuzzy logic,” an ambitious effort to close the gap between mathematics and the intuitive way that humans talk, think and interact with the world, has died.

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Lotfi Zadeh, the computer scientist and electrical engineer whose theories of “fuzzy logic” rippled across academia and industry, influencing everything from linguistics, economics and medicine to air conditioners, vacuum cleaners and rice cookers, died Wednesday at his home in Berkeley, California. He was 96.

Emerging from an academic paper Mr. Zadeh published in 1965 as a professor at the University of California, Berkeley, “fuzzy logic,” as he called it, was an ambitious effort to close the gap between mathematics and the intuitive way that humans talk, think and interact with the world.

If someone asks you to identify “a very tall man,” for instance, you can easily do so — even if you are not given a specific height. Similarly, you can balance a broom handle on your finger without calculating exactly how far it can lean in one direction without toppling over.

Mr. Zadeh envisioned a mathematical framework that could mimic these human talents — that could deal with ambiguity and uncertainty in similar ways. Rather than creating strict boundaries for real-world concepts, he made the boundaries “fuzzy.”

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In academic circles, Mr. Zadeh’s work was controversial and sometimes ridiculed, in part because it challenged other forms of mathematics and in part because of his terminology. “Fuzzy logic” seemed to make fun of itself.

Over the years it proved to be an enormously influential idea. According to the website Google Scholar, Mr. Zadeh’s 1965 paper, titled “Fuzzy Sets,” has been cited by more than 90,000 scholarly works, and his mathematical concepts have provided practical new ways to build consumer electronics, trade stocks, forecast weather and more.

In the 1980s, Mr. Zadeh’s ideas became particularly popular among Japanese manufacturers, thanks to a heavy investment from the government. Today the hype has faded, but fuzzy logic remains an active part of the mathematics that underpin the modern world.

In recognition of his work, Mr. Zadeh received more than 50 engineering and academic awards. From 1963 to 1968 he was chairman of Berkeley’s electrical- engineering department, helping to shift its focus toward computer science, a move that gave rise to one of the world’s top university computer-science programs.