Carl de Boor is extremely humble about his accomplishments over the course of his long career in mathematics. “My contribution is relatively small; I was at the right place at the right time. I saw what needed to be done. Any competent person would have done the same thing.”
All said by the winner of the National Medal in Science in Mathematics (among many other honors) for contributions that are part of algorithms that pretty much run our world. The graphics we see, the curve of lines in the text you are reading, all of that is a function of splines, B-splines in particular, that indicate curves. Computers couldn’t operate without them, and some of the early formulas that Carl developed have become so standard that they aren’t associated with him anymore.
He adds, “I did organize a certain piece of mathematics and come up with the right ideas, in the area of splines, something I came across when working at GM. It was at that point a very new thing. I supplied some algorithms to work with splines and they have become universal.”
Emigrating from Germany with his new bride, Carl had a high school degree when he started graduate classes at Harvard. He transitioned quickly to an early computing position at the General Motors Research Center and made a name for himself working there. At GM, he worked with a leader in splines research who ran the numerical analysis lab (a precursor to computer science). Eventually he attended a two-week summer workshop where lecturers presented on related topics, and he was intrigued by the work they presented. That experience helped him take a closer look at his own lab, and he realized “that the primary difference between him and the Ph.D.s he worked with was that they got paid twice as much and got more freedom.”
Graduate school in Ann Arbor was natural choice at that point. Carl states, “I was an unusual grad student because I had already had papers published. I was independent and had clear view of what I wanted to do.” The first year, he continued to work half time at GM and maintained status as a full time student. As you may expect, he recalls, “It was awful. I got sick at the end of my first semester and ended up in the hospital during finals. After that year, Rackham gave me a fellowship that allowed me to quit my job and move to Ann Arbor with my wife and children. That fellowship made all the difference.”
A recurring regret was that he buckled down and finished his degree in the minimum three years required at the time. He explains, “Because I was married with kids, I needed to go back to work and make money. Now I feel I shortchanged myself and should have stayed another year. There were moments along in my career when I wish I’d know this or that. Graduate school was a very intense three years, but it was a very different experience than my time Harvard. There, it was much more competitive – people wouldn’t even talk to you. At U-M, it was totally different, very much a cooperative venture. I liked that much better.”
Carl finished in 1966, a lifetime ago for many. “Those were the days when you didn’t have to apply for jobs, they applied to you. I got offers from universities all around and settled on job at Purdue because I would be able to work with a former colleague with whom I had already published. In those days, in many ways, that was a very lucky part of my life,” he admits.
The ‘father of splines’ was a long time faculty member at the University of Wisconsin and lured Carl there with a full professorship. “The position didn’t require me to teach, just do research. This gave me time to be a focal point for mathematics and make great contacts,” he says. He mentored numerous graduate students during his tenure at U-W and wrote a seminal introductory textbook on numerical analysis, in addition to countless other publications. Carl retired from U-W after 31 years as a faculty member.
When asked what advice he can offer current graduate students, Carl laughs and says, “Get a Rackham fellowship. It certainly helped me greatly. But really, I think the best advice I can give is to talk in lectures. Actively participate. Ask questions. Be aggressive in that regard.”
He remembers, “My last two years, I didn’t take notes in classes. I listened intently and went home and wrote it all down. I could participate more fully. I had complete lecture notes, but I could see it a little differently. It’s the one time when you have the chance to think along and ask questions.”
Now retired and living on an island off the coast of Washington, Carl has time to reflect on his long career. When asked what stands out as most meaningful in his forty plus years as a faculty member, he answers, “It is doing mathematics. Mathematics for me is very difficult because most of the time, you don’t understand it. You feel like an idiot, but you persist. You have to have a very strong ego in order to withstand weeks and months of feeling stupid. But every once in a while you finally understand, and when that happens there is nothing in the world like it. You’re on top of the world. I’ve been in that position two or three times; it was quite wonderful.”
Carl is writing a book, but he says, “Being retired, there is less urgency to get it done. I’m living at a beautiful space – paradise – and I enjoy the view out of my window. The urgency to work is not there. I do things because I like to; I get a lot less done, but that’s ok too.” Modest again, Carl finally mentions that he still serves on editorial boards in his field and is the treasurer for a fantastic chamber music festival on Orcas Island. I’m learning so much about music and getting to know musicians. It is a part of my daily life, because the organization is dependent on donations, and the day to day operations involve being careful with our funds. As treasurer, I’m careful of money.”
That care extends to U-M as well. Carl has graciously made a bequest in his will to support graduate education at U-M. He explains, “I felt it’s important to acknowledge the help I’ve gotten. I’ve been helped greatly by certain outfits, and U-M, specifically the graduate school, was very helpful to me.”