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    Dr. Y.T. Li, member of the US National Academy of Engineering, Professor of Aeronautics and Astronautic, emeritus of MIT,  is the co- author (with C.S. Draper of Draper Prize fame) of one of the most famous control paper in 1955 long before the term “adaptive control” became well known. Until his retirement from MIT some 30+ years ago, he also simultaneously started a successful industrial company making accelerometers. He is now 97.5(this is not a typo) year old and still going strong. A role model I’d like to emulate if given the chance.
    I came to know Professor Li when I was a graduate student. Professor Li in 1960 sensed the breakout of the new state space control theory and knowing that I was working in this area invited me to have discussions with him on the subject. At that time he was already a well known full professor and I was just a graduate student. But he treated me as an equal and meeting almost every three days over one month time we had a great discussion which also deepened my own understanding of the subject. Subsequently, we become friends, maintained, and shared interest in Chinese-American affairs as well as on technical subjects.
    Professor Li now lives in a retirement community in the Boston suburbs. We still have lunch every few months together. Although physically slowed down somewhat, his mind is sharp as ever. We discuss every subject under the sun during our get together.
    Professor Li’s many accomplishment, too many to report here, are detailed in his autobiography published (in Chinese) eight years ago. See below

(Note added 8/18/2011. I am very sad to report that Professor Li passed away peacefully three days ago. His heart just gave up with little advanced symptom. Personally, I was gratified that he had actually read this blog article of mine and wrote to thank me. We even made plans to get together in September when my wife and I will return from Beijing after our annual visit.)

 
   Long before the matter of innovation in science and technology in China became popular, he wrote an article on the topic of “The Needham Puzzle” which is rather prescient about the subject and well worth re-reading some ten years later. I re-produce it below ( for original source: see page 1 of the documents)