By Lawrence Van Gelder
Thomas S. Kuhn, whose theory of sclentific revolution became a profoundly influential landmark of 20th-century intellectual history, died on Monday at his home in Cambridge, Mass. He was 73.
Robert Dilorio, associate director of the news office at the Massachusetts Institute of Technology, said the scholar, who held the title of professor emeritus at M.I.T., had been ill with cancer in recent years.
"The Structure of Scientific RevoIutions," was conceived while Protessor Kuhn was a graduate student in theoretical physics and published as a monograph in the International Encyclopedia of Unified Science before the University of Chicago Press issued it as a 180-page book in 1962. The work punctured the widely held notion that scientific change was a strictly rational process.
Professor's Kuhn's treatise influenced not only scientists but also economists, historians, sociologists and philosophers, touching off considerable debate. It has sold about one million copies in 16 languages and remains required reading in many basic courses in the history and philosophy of science.
Dr. Kuhn, a professor of philosophy and history of science at M.I.T. from 1979 to 1983 and the Laurence S. Rockefeller Professor of Philosophy there from 1983 until 1991, was the author or co-author of five books and scores of articles on the philosophy and history of science. But Dr. Kuhn remained best known for The Structure of Scientific Revolutions.
His thesis was that science was not a steady, cumulative acquisition of knowledge. Instead, he wrote, it is "a series of peaceful interludes punctuated by intellectually violent revolutions." And in those revolutions, he wrote, "one conceptual world view is replaced by another."
Thus, Einstein's theory of relativity could challenge Newton's concepts of physics. Lavoisier's discovery of oxygen could sweep away earlier ideas about phlogiston, the imaginary element believed to cause combustion. Galileo's supposed experiments with wood and lead balls dropped from the Leaning Tower of Pisa could banish the Aristotelian theory that bodies fell at a speed proportional to their weight. And Darwin's theory of natural selection could overthrow theories of a world governed by design.
Professor Kuhn argued in the book that the typical scientist was not an objective, free thinker and skeptic. Rather, he was a somewhat conservative individual who accepted what he was taught and appiied his knowledge to solving the problems that came before him.
In so doing, Professor Kuhn maintained, these scientists accepted a paradigm, an archetypal solution to a problem, like Ptolemy's theory that the Sun revolves around the Earth. Generally conservative, scientists would tend to solve problems in ways that extended the scope of the paradigm.
In such periods, he maintained, scientists tend to resist research that might signal the development of a new paradigm, like the work of the astronomer Aristarchus, who theorized in the third century B.C. that the planets revolve around the Sun. But, Professor Kuhn said, situations arose that the paradigm could not account for or that contradicted it.
And then, he said, a revolutionary would appear, a Lavoisier or an Einstein, often a young scientist not indoctrinated in the accepted theories, and sweep the old paradigm away.
These revolutions, he said, came only after long periods of tradition-bound normal science. "Frameworks must be lived with and explored before they can be broken," Professor Kuhn said.
The new paradigm cannot build on the one that precedes it, he maintained. It can only supplant it. The two, he said, were "incommensurable."
Some critics said Professor Kuhn was arguing that scieace was little more than mob rule. He replied, "Look, I think that's nonsense, and I'm prepared to argue that."
The word paradigm appeared so frequently in Professor's Kuhn's "Structures" and with so many possible meanings prompting debate that he was credited with popularizing the word and inspiring a 1974 cartoon in The New Yorker. In it, a woman tells a man: "Dynamite, Mr. Gerston! You're the first person I ever heard use 'paradigm' in real life."
Professor Kuhn traced the origin of his thesis to a moment in 1947 when he was working toward a doctorate in physics at Harvard. James B. Conant, the chemist who was the president of the university, had asked him to teach a class in science for undergraduates majoring in the humanities. The focus was to be historical case studies.
Until then, Professor Kuhn said later, "I'd never read an old document in science." As he looked through Aristotle's "Physics" and realized how astonishingly unlike Newton's were its concepts of motion and matter, he concluded that Aristotle's physics were not "bad Newton" but simply different.
Professor Kuhn received a doctorate in physics, but not long afterward he switched to the history of science exploring the mechanisms that lead to scientific change.
"I sweated blood and blood and blood, and finally I had a breakthrough," he said.
Thomas Samuel Kuhn, the son of Samuel L. Kuhn, an industrial engineer, and the former Annette Stroock, was born on July 18, 1922, in Cincinnati.
In 1943, he graduated summa cum laude from Harvard with a bachelor's degree in physics.
During World War II, he served as a civilian employee at Harvard and in Europe with the Office of Scientific Research and Development.
He received master's and doctoral degrees in physics from Harvard in 1946 and 1949. From 1948 to 1956, he held various posts at Harvard, rising to an assistant professorship in general education and the history of science.
He then joined the faculty of the University of California at Berkeley, where he was named a professor of history of science in 1961. In 1964, he joined the faculty at Princeton, where he was the M. Taylor Pyne Professor of Philosophy and History of Science until 1979, when he joined the faculty of M.I.T.
Professor Kuhn was a Guggenheim Fellow in 1954-55, the winner of the George Sarton Medal in the History of Science in 1982, and the holder of honorary degrees from many institutions, among them the University of Notre Dame, Columbia University, the University of Chicago the University of Padua and the University of Athens.
He is survived by his wife, Jehane and three children, Sarah Kuhn of Framingham, Mass., Elizabeth Kuhn of Los Angeles and Nathaniel Kuhn of Arlington, Mass.