Francis Su is a professor of mathematics at Harvey Mudd College and the former president of the Mathematics Association of America. In 2020,  Su published Mathematics for Human Flourishing, which his website describes as “an inclusive vision of what mathematics is, who it’s for, and why anyone should learn it.” The book includes letters from Christopher Jackson, an incarcerated man who corresponded with Su to further his independent math studies. Su will give a talk about his book on Thursday, Mar. 4 at 7:30 p.m. The event is open to the Kenyon community and is sponsored by Phi Beta Kappa. You may register for the event here.

What is your message about mathematics? Why is it important? 

 The main message of the book is that math builds in us. First of all, just like anything that you are attracted to — you think about a passion that you’re interested in, the hobby that you do — we’re attracted to it because we have basic human desires, basic longings. Everybody has a longing for community. Everybody has a longing for freedom. Everyone has a longing for beauty, truth and meaning. And so, what I try to do in the book, but also in the way that I think about mathematics education, is to think, ‘How do I meet the longings that every human being has?’ 

Math education often forgets the human element in what makes mathematics exciting for those of us who do it for a living. Everyone can share in that joy. They don’t have to do it for a living in order to sort of see the beauty of mathematics or to see the wonder — to make sense of the meaning and to enjoy the freedom that comes from thinking mathematically. So these are things that form the basic message of what I’m trying to get across. Math is more than just skills; it’s actually building enough virtues that serve you well, no matter what we do, no matter where we go in life. And when you attend to the deep human desires people have, that’s when you begin to experience mathematics as it’s meant to be experienced. 

We really need to rethink what the purpose of mathematics is: Is it really just to get a good job or a career? Is it only for the elite? Those are ways that sometimes people think about mathematics. But if you think about mathematics as “the purpose of math is to help people flourish,” that’s a … more inclusive way of thinking about mathematics.

The fact that you can take a simple idea — that adding things up into little pieces and putting them back together again — can actually give us powerful answers to important questions, that is amazing. And people should begin to appreciate that. 

Were these ideas intuitive to you, as you began studying mathematics and  your career, or did you discover this framing and how to articulate it later in your career? 

Part of my journey of mathematics is coming from a traditional way of thinking about math and moving more towards a humane way of understanding it. Like everyone else, I was a product of the usual schooling. But then, when I reflect a bit on what I do as a mathematician and why I enjoy math, it’s not because I have to memorize times tables. That’s not what gets me excited about math. What really gets me excited about math is the creativity inherent in it. The big ideas, the beautiful ideas and the experience of freedom possible when you have a new power. 

But when you think about how we teach math, often these things are not the things that are actually valued or measured in the classroom. And of course, it’s hard to measure. It’s easier to measure whether people know how to take 10 derivatives in calculus class. It’s hard to measure creativity. It’s hard to measure systems and problem solving. 

Part of what needs to change in math education is how we assess what it is we want our students to learn and to change the goals that we have for our educational endeavors. And yes, I get it. When you ask somebody to solve five problems on an exam, you hope they exhibit creativity in their answers, but it’s not often an explicitly called-out feature of how we assess what students are learning in mathematics. I think it needs to be a little bit more than we’ve been doing.

Do you have a favorite topic or class to teach? 

I like teaching subjects that have a lot of geometric intuition. Multivariable calculus is a favorite. Linear algebra is also something that I enjoy teaching for that reason because you get to build intuition about how to think and know in many dimensions.

That touches on the point of transferable skills that you talk a lot about in your work. 

Yes. I like to call them “virtues.” But yes, they’re the things that carry over, even if you don’t remember how to factor a quadratic or remember how to do specific things that we often make students learn. It’s the larger virtues that are more important, like building habits of mind that encourage creativity and persistence — valuing struggle. These are all things that, if paid attention to when learning mathematics, can help a lot in terms of having people realize that math really is not about memorizing things. It’s about actually growing in your thinking skills. In many ways, I like to talk about mathematics as equipment for thinking and thinking well.

As a professor, I imagine that you’ve started to incorporate some of this ethic into your classroom. What would the education system look like if this philosophy was mainstream?

Well, one thing I’ve done more recently, as I’ve come to try to think about math more broadly, is to encourage reflection much more in my math courses. Encouraging students to think a little bit about the meaning of things, to describe and experience the mathematical beauty that they’ve had in learning the ideas of the class. These kinds of essay-type questions are less common in math courses than they could be.

But, like everyone else, what I’m also wrestling with is, how do you actually measure what you want to measure? We have a bunch of proxies, but how do you measure creativity in any discipline? That’s a hard question. It’s easy to tell when you see it, but it’s harder to actually have that in the way you grade a class. So that’s a challenge. And this, of course, is partly why, when you have people apply for jobs, you don’t have them just submit a transcript. That’s where, hopefully, letters of recommendation describe a student’s creativity, things that don’t come out under traditional metrics.

Of course, math courses at the more advanced level often have that component. It is often the case that, when encountering somebody who takes a higher math course, they’re like, ‘Whoa, this is beautiful. I’m going to major in math!’ But they would never have been convinced to do that based on their intro courses or their high school courses. Because these are the things that are often taught in a very rote and uninteresting way. It’s kind of like making people practice shooting lots of free throws before they experience the excitement of a basketball game. Nobody wants to sit in front of a hoop and do lots of free throws. But if you can begin to imagine incorporating that as part of the exciting play of the game, you’re like, ‘Okay, I see why I’m doing this.’ Similarly, if you’re teaching music you don’t have people start their musical education by playing lots of scales. You have them experience a symphony. And then they’re like, ‘Whoa.’ They have a vision for what it is they’re going after.

On to the note of inherent beauty, from what I’ve read about your book, it seems like the letters that you exchange with Christopher Jackson were an important touchstone for coming up with this idea and articulating it. Was your correspondence a turning point for how you thought about mathematics or teaching?

I would say my correspondence with Chris enlarged my view of what it is that is possible. Intellectually, before I had this correspondence with him, I assented to the idea that mathematics is something everybody should experience. It wasn’t really until I started hearing from him how his learning of mathematics has transformed him as an incarcerated man seeking to redeem himself. And it wasn’t as simple as correspondence — it became actually real for me. Here’s a person whose life has been transformed by the virtues that he’s building as a result of studying mathematics. And so, certainly, that gave me much more of an appreciation for the message that I was hoping to see.

Who is the audience for this message? Who needs to hear it?

I would say everybody needs to hear it. In many ways, the book itself was written for people who are often discouraged in math. In the book, I tell lots of stories of my own discouragement in math. People are often surprised — I’m a professional mathematician, so it’s a little surprising to hear that the professional mathematician has had bad experiences in math. 

But the other audience I hope to reach is those who see themselves as mathematicians, because it’s very easy for many of us in the profession to have a very narrow view of math: Math is only for the very special, the ones who make it through, the ones who get a Ph.D. And I’m hoping to push back on that idea as well. There are some who do math at an elite level because that’s pushing the boundaries and all of that. But that doesn’t mean that everyone can’t experience the wonder, the joy of discovering or appreciate some of the beautiful ideas in mathematics. 

You’ve talked some about your suggestions for improving the field of mathematics. Do you have a sense of whether other disciplines could improve based on these suggestions? 

In some ways, you could see the book as an argument for the liberal arts. And in many ways, when you hear “the liberal arts,” you think of the humanities. Part of what I am attempting to do in the book as well, by connecting math with basic desires and speaking about habits of mind is to change that position. These are ways that mathematics is a liberal art. Although I don’t say that in the book, I think those who are from other fields, if they read the book, will begin to see how math itself contributes to human flourishing and the habits of the mind that it builds. Anyone who’s at a liberal arts college, like Kenyon, will often hear that it doesn’t matter so much what you major in. Part of what you’re building here is the ability to think critically. I would say math builds that in a very unique way. And that’s part of why everyone should experience it.

This interview has been edited for length and clarity. A shortened version of this interview will appear in the Collegian’s next print edition, which will be published on Mar. 11.