Celebratio Mathematica

David H. Blackwell

Statistics  ·  UC Berkeley

A Tribute to David Blackwell

by Madan L. Puri

If ever a defin­i­tion of grav­itas was sought, one need look no fur­ther than Pro­fess­or Dav­id Har­old Black­well — the first black ad­mit­ted to the Na­tion­al Academy of Sci­ences — who died Thursday, Ju­ly 8, 2010, at age ninety-one. Dav­id had sub­stance; he had weight (in­tel­lec­tu­al weight); he had depth; he was com­pas­sion­ate to the core; and he was genu­ine. In the course of a ca­reer marked by great ac­com­plish­ments in a num­ber of areas in stat­ist­ics, prob­ab­il­ity, and math­em­at­ics, he had earned the repu­ta­tion for in­tel­lec­tu­al rig­or and in­teg­rity, and he com­manded deep re­spect in the glob­al aca­dem­ic com­munity. He was an out­stand­ing per­son, both in­tel­lec­tu­ally and mor­ally, and it is a pleas­ure to say a few words about this noble man.

I will not talk about his sci­entif­ic ac­com­plish­ments. First, they are too many, and second, they are well known. I will con­cen­trate on Dav­id as a man.

On the basis of the per­son­al as­so­ci­ation that I was for­tu­nate to have had with Pro­fess­or Black­well, first as a stu­dent, and then as a col­league, I say with a sense of pride that Dav­id was a rare in­di­vidu­al who pos­sessed warmth, in­teg­rity, hu­mil­ity, in­tel­lec­tu­al pas­sion, a com­mit­ment to stu­dents, fac­ulty, col­leagues, and friends alike. He had the cour­age to take a stand on im­port­ant is­sues — the qual­it­ies that a cre­at­ive, gif­ted schol­ar im­bued with high mor­al sense is sup­posed to pos­sess — and we were for­tu­nate that we had such a per­son as our col­league. I am doubly for­tu­nate to have had him as my teach­er as well.

Good stor­ies al­ways in­vite us to slip in­to the shoes of oth­er people — a cru­cial step in ac­quir­ing a mor­al per­spect­ive. Stor­ies about friend­ships re­quire tak­ing the per­spect­ive of friends, tak­ing them ser­i­ously for their own sake. In the best friend­ship, we see in per­haps its purest form a mor­al paradigm for all hu­man re­la­tions. Pro­fess­or Black­well was a good friend. He had a unique tal­ent, a rare gift of mak­ing every­body and any­body feel as though they were his best and most in­tim­ate friends. His stead­fast friend­ship, his coun­sel, his mag­nan­im­ity, and his ex­ample over many years placed me forever in his debt.

Dav­id was a liv­ing le­gend whose work not only in­flu­enced prob­ab­il­ity, stat­ist­ics, and math­em­at­ics but has also had far-reach­ing im­plic­a­tions for many fields, in­clud­ing eco­nom­ics. To quote him, “I’ve worked in so many areas — I’m sort of a di­let­tante. Ba­sic­ally, I’m not in­ter­ested in do­ing re­search and I nev­er have been. I’m in­ter­ested in un­der­stand­ing, which is quite a dif­fer­ent thing. And of­ten to un­der­stand something you have to work it out your­self be­cause no one else has done it.” He re­ceived his Ph.D. in 1941 at the age of twenty-two from the Uni­versity of Illinois un­der the dir­ec­tion of Pro­fess­or J. L. Doob, and he dir­ec­ted sixty-five Ph.D.s. It is well known that in 1942 Jerzy Ney­man of the Uni­versity of Cali­for­nia at Berke­ley asked Doob if he was in­ter­ested in go­ing west. “No, I can­not come, but I have some good stu­dents, and Black­well is the best,” he replied. “But of course he’s black,” Doob con­tin­ued, “and in spite of the fact that we are in a war that’s ad­van­cing the cause of demo­cracy, it may not have spread throughout our own land.” Ney­man then wanted to of­fer Black­well a po­s­i­tion, but the idea met with protest from the wife of the math­em­at­ics de­part­ment chair­man. She was a Texas nat­ive who liked to in­vite the math fac­ulty to din­ner oc­ca­sion­ally, and she said she “was not go­ing to have that darky in her house”, ac­cord­ing to Dr. Black­well’s re­col­lec­tion in an or­al his­tory in­ter­view. The job of­fer nev­er came. Ney­man had nev­er for­got­ten Black­well and fi­nally hired him in 1954, and Black­well would stay at Berke­ley for the re­mainder of his ca­reer.

As a teach­er he kept his ex­pect­a­tions high. When the stu­dents walked in­to his class, they felt the spir­it of ex­cel­lence. He saw to it that no stu­dent was left be­hind. He made every ef­fort to see that at the end of the day, the poor stu­dent be­came good and the good stu­dent be­came su­per­i­or. Stu­dents were his audi­ence. He nev­er walked away from them as long as they did not walk away from him. As long as they were buy­ing what he was selling, he kept on selling. He was the shin­ing light.

Pro­fess­or Black­well re­ceived many hon­ors in his life­time, which in­clude, among oth­ers, elec­ted mem­ber­ship in the Na­tion­al Academy of Sci­ences (the first and the only black math­em­atician) and the Amer­ic­an Academy of Arts and Sci­ences, pres­id­ent of the In­sti­tute of Math­em­at­ic­al Stat­ist­ics, vice pres­id­ent of the Amer­ic­an Stat­ist­ic­al As­so­ci­ation, vice pres­id­ent of the Amer­ic­an Math­em­at­ic­al So­ci­ety, and twelve hon­or­ary de­grees of doc­tor­ate of sci­ence from Har­vard, Yale, Carne­gie Mel­lon, and oth­er uni­versit­ies.

We live in a dif­fi­cult world; we live in a com­plic­ated world; a de­mand­ing, un­for­giv­ing world, a world in which hon­esty and in­teg­rity are be­com­ing rare com­mod­it­ies; where malice, jeal­ousy, and self-centered­ness mo­tiv­ate people to act in un­pro­fes­sion­al, un­eth­ic­al, and un­desir­able man­ners. Iron­ic­ally, and pain­fully, these things are hap­pen­ing even in the aca­dem­ic world, which is sup­posed to be the mor­al voice of hu­man­ity, but dur­ing these dif­fi­cult and com­plic­ated times, in this de­mand­ing and un­for­giv­ing world, Pro­fess­or Black­well mastered the art of liv­ing the dif­fi­cult life with in­teg­rity and style, and he made it look easy and cer­tainly de­sir­able. He showed his strength by sid­ing with the weak and help­ing the down­trod­den, and with his loy­al heart and with his purest hands, he ex­ecuted faith­fully the uni­versity, pub­lic, and pro­fes­sion­al trusts. Any­body who knew him, or met with him, re­spec­ted him, revered him for his bright sunny nature and the saintly un­selfish­ness by which or with which he dis­charged his re­spons­ib­il­it­ies and earned the re­spect and trust of his friends and col­leagues. The math­em­at­ic­al com­munity in gen­er­al, and those who knew him out­side the math­em­at­ic­al com­munity, loved him while he was liv­ing; they love him even now when he is gone.