Francis Su: How does mathematics contribute to human flourishing?

For many people, math feels cold, distant, boring and even unpleasant. The math classroom can be a place where people are marginalized and even shamed.

But it shouldn’t be that way, says Francis Su, the Benediktsson-Karwa Professor of Mathematics at Harvey Mudd College.

“Those of us who do math for a living actually are drawn to math often because of this exploratory nature, and we love the creativity,” Su said. “The argument that I make is that these virtues carry over to other areas of your life.”

Su’s book “Mathematics for Human Flourishing” is influenced both by his work as a mathematician and teacher and by his Christian faith. It’s based on a speech he gave in 2017 as the outgoing president of the Mathematical Association of America, where he was the first person of color to serve in that role.

The speech brought the audience to its feet — and some listeners to tears — as Su expressed his inclusive vision of the field of mathematics. Illustrating this vision, the book is interspersed with letters about math that Su has exchanged over the years with Christopher Jackson, who is an inmate at a high-security federal prison.

Su has received national awards for teaching and writing, and “Mathematics for Human Flourishing” won the 2021 Euler Book Prize. He holds a Ph.D. from Harvard University.

He spoke to Faith & Leadership’s Sally Hicks about how his faith and work reflect the same desire for beauty and truth. The following is an edited transcript.

Faith & Leadership: On your website, you say, “My book is about the elevation of human dignity, and how we are using math to raise people up or tear people down.” That’s not necessarily what people expect from a book about math. What does that mean?

Francis Su: I like to say that my book is about what it means to be a human being, and math is a lens on that: What does it mean to do mathematics from the point of view of growing as a human being?

It connects deeply to the humanities and the human person — the human spirit. The big thread running throughout the book is, How do we dignify people? What contributes to human dignity?

Certainly, an example is the story of my friend Christopher Jackson, who is an incarcerated man who discovered math in prison. We’ve had a long-running correspondence for many years now, but he initially wrote me because of his interest in mathematics.

Here is an example of a person society has thrown away and forgotten. He’s a featured contributor to the book, and if you read the book, you’ll read many of his letters. I think you really get a sense of a person who, even though society has forgotten him, is flourishing because of the dignity that God has given him, to use religious language.

In spite of all the obstacles, the setbacks that he faces, his own wrestling with his past actions, he is now in a place where you see the God-given dignity that he has. So that’s a theme.

Another theme is when you think a little bit about what we do in a math classroom or the way we teach mathematics, we often teach math as a bunch of rules to memorize, facts you need to know, rather than as a creative activity that people can enjoy. So the math classroom can often feel very stifling and oppressive. Many people have had traumatic experiences in math.

Even somebody like myself, who has been interested in math and pursued math for a while, has had hard experiences in math. I tell a story in the book about how in graduate school I was written off by a professor who didn’t think that I could be a successful mathematician.

That’s another theme throughout the book that you see as my story unfolds — somebody who most people, from the outside, would look at and say, “Whoa, this person has had a successful career in math and went to Harvard and got his Ph.D.”

And yet one of the things that you also hear throughout the book is my own wrestling with, “How do I need to reshape and rethink what it means to do math?”

Initially, it was easy to say math is about performance — it’s about getting a Ph.D. and being seen as good. Then by the end of the book, I think you can see how I’ve come to realize that math actually shouldn’t be that, even though people often perceive it that way.

That’s more of an elitist view of math that I think too many people have.

F&L: Why did you structure the book the way you did?

FS: The book’s chapters are all structured around a basic human desire, starting with the chapter on flourishing. This is a notion borrowed from philosophers who ask the question, “What does it mean to live life well?”

The other chapters are organized around desires like the desire we have for beauty, for truth, the longing we have for freedom, for community.

The last chapter in the book is on love. It’s unlike what people might think from a math book — it’s not about the love of math.

It’s actually about the love of people. One of the points that I make in the final chapter is that if you love someone well, [you] believe that they can flourish in mathematics.

Within each chapter, I talk about the virtues that are built by pursuing math through the lens of that desire.

For instance, we all have a desire to explore. When we do math or do anything through the lens of exploration, it often builds in us virtues like creativity.

When you are exploring an unfamiliar terrain, going on a hike, venturing into a cave or trying to get to the moon, these are all places where you have to exercise creativity in order to meet that challenge of getting to where you want to go.

I think that’s a better answer to the question, “Why do math?” People ask, “Why do I need to learn this stuff?” The usual answer isn’t satisfactory.

The one we often tell kids is, “Because you’re going to need it later.” Actually, that’s often not even true. The stuff through eighth grade, yeah, you’ll need that later. But a lot of the math you learn in high school is not going to be used later, especially calculus.

Unless you’re going to be a scientist, you’ll probably never use calculus. So why are students scrambling to take it? Often, it’s because they think they need it to get into college; they need it to be credentialed in some way.

But I think a better answer to the question, “What do you actually get out of a calculus class?” — or any math class — is, “You’re building certain virtues, and these are the virtues that employers are looking for.”

If you want to get practical, an employer probably doesn’t care whether you can factor or know the quadratic formula. They care that you’re creative, that you’re persistent at problem solving, that you are willing to tackle problems you’ve never seen before.

These are all things that do carry over to other areas of life, and the practice of mathematics, when done well, will build them.

F&L: Your book is clearly imbued with Christian values (although you don’t evangelize about anything other than math). What’s the connection between your work as a mathematician, writer and public intellectual and your Christian faith?

FS: I’ve been strongly influenced by many Christian thinkers in how I think about what it means to be a human being. So it’s very natural if I’m writing a book about what it means to be human, even through the lens of math, that many of those ideas would find their way in the book. I don’t shy away.

Actually, if it’s a book about being human, it’s also hard to avoid it being a spiritual book in some sense. Whether you’re actually an adherent to some faith or even no faith at all, we’re all spiritual beings.

So it’s hard to shy away from asking deep spiritual questions, because they’re deep human questions.

Why is it that I long so deeply for permanence? There’s a whole chapter on permanence, which is another way of talking about the eternal.

The chapter on play has been influenced strongly by sermons that I’ve heard about the nature of play and why we play.

There is a chapter on justice. That resonates very deeply with the idea that I find in my own Christian tradition to elevate those who are poor and oppressed and marginalized.

The outcasts of society are the ones that Jesus paid the most attention to, and so I think the same ought to be true in the way we think about who we offer math to, who math is for. In that sense, it’s an outworking of my own concern and care for the poor, which comes out of my own faith practice.

F&L: Do you think that when you received that letter from Chris Jackson from prison you were more open to it because of your formation as a Christian?

FS: I believe so. Just to say a little bit on my own Christian formation: I did not grow up in a religious household, and I didn’t actually become a follower of Jesus until college.

I think following Jesus has changed me in deep ways. It’s made me more of a people person. It’s given me more of a heart for the marginalized, and it’s given me a deep appreciation of the spiritual and of thinking deeply about big questions.

I’ve grown as a result of my faith, and so responding to somebody who writes me a letter out of prison — I mean, sure, it would tug at anybody’s heartstrings. But I think I felt more of a call to really engage because of my own faith.

F&L: There may be a broad assumption that folks in STEM fields might not be religious or that faith and math or science are incompatible. Do you see that as any kind of tension or debate?

FS: I don’t see incompatibility at all. In fact, I see deep resonance.

In my own experience, it seems that there are a number of scientists who are believers. Part of why we are attracted to science is also related to part of what attracts us to our faith tradition, with the desire for beauty and truth being chief among them.

Scientists are on the quest for truth. It’s a different kind of truth from religious truth, but it’s a quest very similar in many ways, and so there is a deep resonance, I think.

I think that highway runs both ways. When somebody talks about God being infinite or eternal, I think I have a deeper appreciation of what that means because of my math training.

I understand how interesting and complex the infinite sets are, and the fact that there are actually different levels of infinity is sort of a mind-boggling thing when you first encounter it in math.

F&L: You focus a lot on math teaching, and you even wrote an op-ed about how to avoid microaggressions in teaching math. You’re making a pretty deep argument about that.

FS: If you think of math as solely about performance, then it feeds into society’s obsession with achievement.

It tends to elevate, to amplify, inequities when you think about who has access to a great education and who doesn’t. People get competitive, and that’s a vision of math that I don’t like. I’m not saying you shouldn’t have fun math competitions.

There’s a certain elitism that people have around math that I think is very harmful and I want us to stay away from. What should the math classroom feel like? It shouldn’t feel like a prison. It shouldn’t feel like a bunch of people giving orders and you just follow them.

Math class should be a place of thinking. It should be a place of exploration. It should be a place of play, a place of creativity and a place of enjoyment.

A math classroom shouldn’t feel like shooting a bunch of free throws and never playing a basketball game. Math class shouldn’t feel like learning to play scales and never hearing a symphony.

Learning drills, scales or working out — these are all important things, but they’re only important if you ask, “What’s the end?”

In math classes, it’s often hard for students to see the end, and that’s what we should be helping our students experience.

The end is beauty and joy and appreciation and growth, learning to think well. These are all things that can be eminently enjoyed and experienced by everybody, not just people who get math Ph.D.’s.

F&L: Is there anything I didn’t ask that you would want to add to this conversation?

FS: I would encourage pastors and other people of faith to have a more expansive view of what it means to do math and science, to appreciate that scientists actually are concerned about the truth and carefully recording truth, and to see them as moving toward similar ends with people of faith.

And math is in some ways one of the most pristine ways of recording truth, of knowing truth, a certain kind of truth.

Often in my own faith, I’m attracted to beautiful ideas — the beauty of grace, the beauty of the gospel — and there’s a sort of similar feeling you get by appreciating that sublime form of beauty that I think everybody should have a chance to appreciate.