Hartley Rogers, Jr.

Hartley Rogers, Jr. was a mathematician who worked in recursion theory, and was a professor in the Mathematics Department of the Massachusetts Institute of Technology. The Rogers equivalence theorem is named after him.
Born in 1926 in Buffalo, New York, he studied under Alonzo Church at Princeton, and received his Ph.D. there in 1952. He served on the MIT faculty from 1956 until his death, July 17, 2015.
There he had been involved in many scholarly extracurricular activities, including running SPUR (Summer Program in Undergraduate Research) for MIT undergraduates, overseeing the mathematics section of RSI (Research Science Institute) for advanced high school students, and coaching the MIT Putnam exam team for nearly two decades starting in 1990, including the years 2003 and 2004 when MIT won for the first time since 1979. He also ran a seminar called 18.S34: Mathematical Problem Solving for MIT freshmen.
Rogers is known within the MIT undergraduate community also for having developed a multivariable calculus course (18.022: Multivariable Calculus with Theory) with the explicit goal of providing a firm mathematical foundation for the study of physics. In 2005 he announced that he would no longer be teaching the course himself, but it is likely that it will continue to be taught in a similar manner in the future. He is remembered for his witty mathematical comments during lectures as well as his tradition of awarding Leibniz Cookies and Fig Newtons to top performers in his class. His doctoral students included Patrick Fischer, Louis Hodes, Carl Jockusch, Andrew Kahr, David Luckham, Rohit Parikh, David Park, and John Stillwell. Rogers won the Lester R. Ford Award in 1965 for his expository article Information Theory.
In his spare time, he served for many years as the Chaplain for the World Indoor Rowing Championships as part of the C.R.A.S.H.-B. Sprints Board of Directors.
An avid oarsman, he was most recently a member of the Cambridge Boat Club on the Charles River, Cambridge, MA.

• "That was a horrible misconception...and your misconception is even more horrible."
• "That would be like my saying, 'All unicorns in the Boston Zoo are purple.' That's true even though there are no unicorns in the Boston Zoo, because if you were to find one there, it would be purple." [See vacuous truth.]
• "What's incorrect is your wrong idea... Maybe you don't have the wrong idea. Maybe I'm fighting a strong person."
• [On drawing an odd-looking graph on the chalkboard] "This graph doesn't actually look like that — but since I didn't label the axes I can do anything I want!"

• "Recursive functions over well ordered partial orderings". Proc. Amer. Math. Soc. 10: 847–853. 1959. doi:10.1090/s0002-9939-1959-0111685-8. MR 0111685. 
• with Donald L. Kreider: "Constructive versions of ordinal number classes". Trans. Amer. Math. Soc. 100: 325–369. 1961. doi:10.1090/s0002-9947-1961-0151396-x. MR 0151396. 
• "On universal functions". Proc. Amer. Math. Soc. 16: 39–44. 1965. doi:10.1090/s0002-9939-1965-0171705-4. MR 0171705. 
• Hartley Rogers, Jr., The Theory of Recursive Functions and Effective Computability, MIT Press, ISBN 0-262-68052-1 (paperback), ISBN 0-07-053522-1 (textbook)

• Yates, C. E. M. (March 1971). "Review: Theory of recursive functions and effective computability, by Hartley Rogers, Jr". J. Symb. Logic. 36 (1): 141–146. doi:10.2307/2271523. JSTOR 2271523.