Celebratio Mathematica

Irving Kaplansky

Kap at MSRI

by David Eisenbud

Kap was enorm­ously in­flu­en­tial in many fields of math­em­at­ics, through his pa­pers, through his books, and per­haps most of all through his Ph.D. stu­dents and the many many ad­di­tion­al stu­dents who, like my­self, listened raptly to his courses. I re­mem­ber well his highly en­ter­tain­ing and beau­ti­fully pol­ished lec­tures from my stu­dent days in Chica­go — whatever he taught, I signed up for the course, it be­ing such a pleas­ure to listen to him. From be­ing on the first win­ning team of the Put­nam com­pet­i­tion to be­ing pres­id­ent of the AMS and Na­tion­al Academy mem­ber, his ca­reer was truly re­mark­able — you can find more in­form­a­tion start­ing from the AMS web­site, ht­tp://­plansky.html.

As the second dir­ect­or of MSRI, Kap served the In­sti­tute dir­ectly from 1984 through 1992. He greatly de­veloped the repu­ta­tion and in­flu­ence of MSRI, build­ing on the start provided by the founders, Chern, Moore, and Sing­er. My own first ex­per­i­ences at MSRI were un­der Ka­plansky’s dir­ect­or­ship. As with everything he did, he paid at­ten­tion to every de­tail of the op­er­a­tion — he boas­ted to me once that he per­son­ally read and signed every single let­ter of in­vit­a­tion that the In­sti­tute sent out dur­ing his eight years in of­fice. He and his wife, Chel­lie, were also very present and avail­able to the mem­bers — lit­er­ally thou­sands will re­mem­ber Kap’s mu­sic­al per­form­ances at the Christ­mas parties. Among the many marks Kap left on MSRI was the start of fun­drais­ing activ­ity. For ex­ample Kap formed the “In­ter­na­tion­al Board of Friends of MSRI”, and the con­nec­tions made through this group are still of the ut­most im­port­ance to us. Kap’s first pa­per ap­peared in 1939. After step­ping down as MSRI dir­ect­or, at sev­enty-five, Kap went back to full time re­search math­em­at­ics, and re­turned to num­ber the­ory, one of his first loves. Some of his most re­cent work, on in­teg­ral quad­rat­ic forms, was pub­lished in 2003, when he was eighty-six.

Math­em­at­ic­ally, Kap was my broth­er: he, the first stu­dent of Mac Lane, I, nearly the last. But he was much more an uncle to me who had been down most of the av­en­ues that I later began to ex­plore. He was al­ways gen­er­ous in ad­vice, coun­sel, and in giv­ing cred­it. I saw him nearly every day in my stu­dent days at Chica­go, and again, nearly every day, over the first eight years I was MSRI dir­ect­or. In­ter­act­ing with Kap was al­ways a pleas­ure, crisp, clear, and some­how up­lift­ing. It is one that I shall deeply miss.