Francis Su

Francis Su

Francis Su (ΦBK, University of Texas) is the Benediktsson-Karwa Professor of Mathematics at Harvey Mudd College. He has previously served as president of the Mathematical Association of America, and his speeches and writing have earned acclaim for describing the humanity of mathematics, and for calling people to greater awareness of issues that contribute to inequitable mathematics education.


As a child, what profession did you envision for yourself when you grew up? 

I loved reading science books as a kid, so I dreamed of becoming an astronaut, but I think I was scared away from that when I realized how much physical preparation that would require. I also very much loved mathematics. I remember being fascinated by patterns in numbers, as well as clever ways to take advantage of them. 
For instance, here’s a simple way to multiply a 2-digit number by 11: take the two digits, add them, put their sum in between. So you can multiply 35 by 11 by adding 3+5 to get 8, so 35 x 11 = 385. Why does that pattern hold? If you think about it awhile, or use a little algebra, you may be able to understand what happens. Doing so will also prompt you to explore what breaks with this pattern when the sum is larger than one digit (try 94 x 11) and how to modify the pattern to make it work again (I’ll let you figure that out).
As I learned more math, I got even more excited when I realized math didn’t have to be about numbers at all. Mathematicians study many other patterns, like shapes, or patterns in data, or models of how people interact. Best of all, you could think about interesting problems anywhere---you didn’t need a special lab or equipment to do your thinking. You only need your mind! As I like to say, mathematics makes the mind its playground.

What was the most transformative course from your undergraduate education?

The most transformative course I had as an undergraduate was Dr. Michael Starbird’s Topology course. He taught it using an inquiry method, in which we were coaxed to make discoveries for ourselves. We were given problems to think about, and we came to class prepared to present our ideas. The act of talking out our ideas to refine them, and seeing multiple ways of proving the same theorem was eye-opening to me. I developed a lot of confidence in that class that I could do mathematics, and I saw how beautiful it was.

What is your favorite part about your job?

I love helping students understand the power of ideas, and I enjoy seeing the light bulb go on when they grasp a concept or discover something new. Sharing that moment is a privilege. Often my students help me see new things too, which makes my job continually refreshing. And remaining in touch after they graduate, seeing how they progress and grow, is a real treat.

You previously participated in the Phi Beta Kappa Visiting Scholars program.  What was most rewarding about that experience?

I very much enjoyed visiting several campuses, and engaging with students about big ideas. Most people have a hard time thinking of mathematics as something that connects to their humanity, so I enjoy releasing people of their pre-conceived notions of what mathematics is. I want them to see how it can enrich the human experience.

You also recently published your book Mathematics for Human Flourishing, a topic which you spoke about briefly at our (En)Lightning Talks Los Angeles event. What is your new book about, or what lessons do you hope readers take away?

Many fans of the book say it is hard to describe, and that’s because it doesn’t really fit into any category. 
I like to say my book is not really a math book—rather, it’s a book about what it means to be human, using mathematics as a lens. It’s also a book about desire—for the deep human longings we all have, such as for beauty, for truth, for justice, for love. So it may speak to our current national moment—fighting disinformation about the pandemic, thinking about racial justice—more than I might have expected when I wrote it. And it’s a book about virtue—in a broader sense than perhaps Aristotle would be comfortable with.  
Running throughout are personal stories of three people: Simone Weil, a French mystic-philosopher, Christopher Jackson, an inmate with whom I’ve had a long correspondence, and me, who perhaps pursued math for the wrong reasons and was wounded by harsh judgments about my own capabilities.  My earnest hope is that readers will begin to see the human side of mathematics, find it attractive, and begin to envision themselves as capable ‘math people’. The basic message of the book is that doing math is part of what it means to be human being, and it can bring joy!

Do you think Phi Beta Kappa and a well-rounded, liberal arts and sciences education are important in today’s society?

Most definitely. In many ways, you can view my book as a broad argument for mathematics as a liberal art. Math isn’t just something you do to get a good job, or to calculate a tip. The practices of mathematics—training the mind to think carefully, to reason well, and to experience joy in deep understanding—can serve everyone, no matter what profession they go into. A broad training in the liberal arts and sciences can also help us wade through our current national mess of polarization and disinformation, to figure out for oneself what is really true, to help us understand how we got here as a society, and to encourage creative thinking about how to fix it.

What advice do you have for young Phi Beta Kappa members?

Keep learning and growing. Be a person of humility and grace. Make deep friendships a priority, especially with people who will love you and be your friend regardless of how ‘successful’ you are. Be that friend to others… everyone needs a friend like that. Don’t be tempted by success. Figure out who you are, how you flourish, and how you can help others flourish too. 

What book are you reading right now? Are you listening to any podcasts or watching any shows? Anything you'd recommend? 

Well, I just started reading Zena Hitz’ book Lost in Thought: The Hidden Pleasures of an Intellectual Life, and highly recommend it!  I wish I had known about her book when I was writing mine—we have much in common in the ways we think about what education is for.