Remembering David Blackwell

Remembering David Blackwell

Memories from former students

I would never have stayed in graduate school if it weren't for David Blackwell. I was bored, broke, intimidated, and thinking about getting a job in the computer industry when I saw David give a talk about Gale-Stewart games. Even though I was already in the Statistics department, the talk changed my life. I was hooked. It was like reading a great novel: I couldn't stop until I finished my thesis. Not only was David inspiring, he taught me more in a handful of twenty-minute discussions than I learned in years of tedious classes. I learned about mathematical rigor and elegance from David, who solved complex problems in a few lines. I learned that if I didn't think thoroughly about something because I was confident in my intuition, there were probably holes in my argument, and David would find the holes in 30 seconds. So I tried, not always successfully, to be rigorous, knowing that David would quickly uncover anything I overlooked. To me, David symbolized what mathematical inquiry is supposed to be about.

Mike Orkin, PhD, 1970

So now they’re all gone, my three mentors, in a little less than two years, David Freedman, Lester Dubins, and now David Blackwell. I first met Professor Blackwell when I returned from Europe to start graduate school and became a TA of his in Stat 2, using his book *Basic Statistics,* based ingeniously upon Bayesian statistics. I taught the students happily under his tutelage, but soon found that they responded well to some different approaches I had found. After a few semesters TA’ing under him and using his extraordinary book, I began to teach the material a little differently, making my own detours and side trips, and found that the students seemed to understand the ideas quickly and with more ease.

After some time, I, a lowly TA and second year graduate student with little teaching experience, began to imagine that I could teach an entire lecture course in that way. And one unthinking afternoon, in a fit of hubris and chutzpah, I went to see him in his office on the 3rd floor of Evans and told him I had some other ideas about how to teach elementary statistics in Stat 2, and said that I would like to lecture the course. I don’t know what I expected, perhaps just to put my name in the hat for future reference, but his response was immediate. He leaned back in his chair and said, “Why, I think that would be marvelous!” I didn’t have to speak with anyone else about it; he set it up and the next fall I was a lecturer, with a collection of TA’s myself.

Professor Blackwell was never my mentor in any guiding sense, was not even on my PhD committee, but I have always credited his generosity and innate kindness with starting me on a path that lasted for another 15 years as a lecturer in the department, which in many ways determined the course of my life and continues to do so even today over 40 years later. I attended his seminars with eagerness, as I was always absorbed by the crystalline clarity of his thoughts and thought of him as one of the clearest stars on my horizon. I sadly never went to him with any of the many problems I considered, having fallen under the gracious spells of Lester Dubins and David Freedman, but I always received a generous smile from him, whatever I wanted to do and whatever ideas I had. I remember me passing his table after my talk at Lester’s 70th birthday party, him smiling and nodding with encouragement at what I’d said.

I haven't seen him for many years, but even in his absence I have always felt his presence when I come to the department. He was a bright light in the great firmament of mathematicians I knew, and his brilliance and radiant generosity will always remain in my mind.

Robert Pisani, PhD