I just got off the phone after a call with John Markoff of the New York Times, who has been asked to write the obituary for Jack Schwartz, who died yesterday at the age of 79. Peter Capek had given my name to John, and John asked me to talk of my years with Jack.
John and I spoke for over half an hour, during which I learned that John knew both John Cocke and Ken Kennedy. Both, like Jack, are sadly no longer with us. Ken was the first Ph.D. in Computer Science at NYU/CIMS; Jack was his thesis advisor. Jack was also my thesis advisor.
It will be interesting to see which, if any, of my observations make it into print.. Here are a few of the key points I tried to make:
Jack was a world-class mathematician. While at Yale as a post-doc, his collaboration with Nelson Dunford resulted in one of the fundamental works in mathematics in the last century, a multivolume work known to mathematicians worldwide simply as Dunford and Schwartz. This work established both his reputation and that of the Yale Mathematics Department. 
Jack was similar to the great mathematician David Hilbert in that, as Wikipedia puts it, “He invented or developed a broad range of fundamental ideas in many areas.”
In Jack’s case these fundamental areas included: creating SHARER, the first timesharing system for the CDC 6600 computer, then the world’s fastest computer; program optimization, as expressed in the classic “Cocke and Schwartz; Programming languages and their compilers : preliminary notes;” creating SETL, a programming language based on finite set theory, that served as the inspiration for the Python language; ultracomputers, and his work on robotics. 
Jack’s collaboration with the legendary IBM computer scientist John Cocke is but one instance of the several cases known only to his colleagues in which Jack’s efforts brought recognition to people who would otherwise have not gotten the credit that was their due.
For example, Jack was the first person to bring to the attention of the Western world the work of Andre Ershov, who did fundamental work in program optimization in the USSR in the early 1960’s.
Jack also helped to publicize the pioneering work on program optimization byf John Cocke and Fran Allen of IBM. 
Greg Chaitin of IBM Research, like Jack world-class mathematician, would be much less well-known were it not for Jack. While an undergraduate at the City University of New York in the mid 1960’s, Greg independently discovered what is known as “Kolmogorov Complexity.” Jack traveled widely, and around 1972 or so he was in Argentina when he learned that Greg was working in Argentina as a systems programmer for IBM. Jack immediately got on the phone to John Cocke at Research, and told John to bring Greg to Yorktown. When he arrived at Yorktown, Greg joined that legendary “801 Project” that resulted in RISC architecture. Greg worked on the then unsolved problem of register allocation. He solved it, by first showing that it was computationally near intractable in that it was equivalent to a problem in coloring a graph, and then finding an efficient approximation known as Chaitin’s algorithm.
Jack was also one of the first computer scientists to visit China following President Nixron’s historic trip to China in 1972. 
On a personal note, Jack was also the brother-in-law of the literary critic Alfred Kazin.
During our call I mentioned that Jack was on my personal list of the five smartest people, and that John’s colleague at the New York Times, Tom Friedman, was Smart Guy #5. I said that one of the goals in writing this blog was to get Tom to enter a comment to my post HELLO Tom Friedman. John said he would pass on the request to Tom, so readers of this blog will be able to join me in learning if John has real clout.
1. My youngest daughter attended Yale, and whenever I happened to walk by the small building that housed the Yale Department of Mathematics, I thought of Jack and his years in New Haven.
2. See my recent post On “Farewell World” and Programming for the influence of SETL on Python.
SHARER was possible only because of a marvelous programming hack due to Jack. I will write about it in a future post, “Jack’s Hack.”
3. Jack mentioned to me that he wrote most of “Cocke and Schwartz” while serving as a juror on a trial that went on for several months.
4. Jack knew the nephew of Chou En-Lai’s interpreter. (I forget the name, but recall he taught at a college on Staten Island.) Jack gave a series of lectures in China, during which he began the translation of the terminology of computer idioms into Chinese. He found “hash” particularly hard to translate.