Jason Zesheng Chen is a logician and philosopher of mathematics who studies the foundations, history, and methodology of mathematics (especially descriptive set theory and the higher infinite). Having obtained a Ph.D. under the supervision of Toby Meadows at the Department of Logic and Philosophy of Science, UC Irvine, he is currently employed as product marketing manager for developer relations at Intuit and serves on the APA’s Non-academic Careers Committee.
Personal Website: https://jasonzeshengchen.github.io/
What excites you about philosophy?
Its eclectic nature. I am trained in a style of research that places value in the faithful documentation and analysis of the actual practices of experts in certain technical fields. Sometimes this line of work runs the risk of being too removed from the immediate advancement of such fields. (The rather polemical analogy is “as useful as ornithology to birds,” but I’d like to think of it as a kind of ethnography of certain specialized expertise.) Other times it may be deemed too down-to-earth to address the Big Questions of what there is and what is right or wrong. Nevertheless, I think there is intrinsic joy in being able to understand and articulate something clearly and deeply, to make explicit what is already implicit (to quote from Penelope Maddy, one of my philosophical role models), and I remain humbled by the privilege of being able to find a home in philosophy for this kind of work.
What is your favorite thing that you’ve written?
Aside from my public expository pieces, I am quite fond of the first two chapters of my dissertation, currently under review as standalone articles, so stay tuned! It’s a systematic taxonomy of the kinds of possible evidential import from confluence phenomena in mathematics (roughly speaking, when you have a large number of equivalences) and how mathematicians have appealed to them in actual practice. This is an interesting methodological study of a salient mathematical practice that has seen growing attention in recent years, and I tried to identify its occurrences across numerous mathematical disciplines, with a diverse range of purposes largely orthogonal to each other.
What are you most proud of in your professional life?
Whether it’s my academic life with mathematicians and linguists, or my corporate life with developers, I’ve always tried my best to gain the same lived experiences as my “subjects”—undergoing the same training, immersed in the same working environment, and subject to the same standards.
What are you working on right now?
A few things, top of mind is carefully tracing the emergence of a hitherto unnoticed foundational role that is played by set theory; come to my ASL/APA Central 2026 joint meeting talk to learn more! There is also an analysis of the way mathematicians classify proofs by the methods that are employed in them—when can we say two proofs are definitely distinct by virtue of using different methods, and when are two proofs with apparently different methods “really just the same proof”? Another one is a study of the bases on which generative syntacticians have decided what grammatical rules are preferable, and the remarkable parallels to how set theorists decide what axioms they accept.
Outside of research, I’ve also been exploring and experimenting with how one may effectively communicate philosophy via more diverse media (audio, visual, conversational, etc). I wonder if it is possible for philosophy to have its 3Blue1Brown.
What do you like to do outside work?
In my free time I do quite a bit of expository writing for the general public in both Chinese and English. I am pretty proud of my 27,000 and growing readers across multiple platforms; I’d like to think that I contributed my meager share to the rising popularity of mathematical logic and philosophy of mathematics in China.
When I am not sitting in front of the screen, I like to play soccer—a very long time ago I was on track to become a professional soccer player—cook, go fishing, sharpen my own knives, do really amateur latte art, and practice general DIY house maintenance and plumbing, often to the amusement of my cats. And although we are very bad at it, my partner and I and a couple of close friends like to indulge in the guilty pleasure of a certain battle royale video game. I am also an avid learner of as many languages as possible; in fact this is what got me into philosophy in the first place!
Who do you think is the most underrated philosopher?
Alan Turing. He’s so underrated that most people don’t think of him as a philosopher! I am constantly amazed by his seminal paper “On Computable Numbers, with an Application to the Entscheidungsproblem”—the paper in which he introduced the Turing Machines—pinpointing an intuitively salient notion and presenting a rigorous analysis of it (at a time when such an analysis was definitely needed), delineating its range and limitations precisely, complete with attendant justifications of why the attempted formal analysis should be right. I think it might have been Frank Gehry who said great architecture is the kind that, when you see it, you won’t think architecture. To me, Turing’s “On Computable Numbers” is the epitome of great philosophy.
Where would you go in a time machine?
The driver’s seat. (Assuming it’s shaped like a car.)
Which superpower would you like to have?
The ability to think of the right word at the right time. Also, if I find others like me, I get to form the le-mot-juste-ist league.
What’s your favorite quote?
“Be it grand or slender, burrowing, blasting, or refusing to sanctify; whether it laughs out loud or is a cry without an alphabet, the choice word, the chosen silence, unmolested language surges toward knowledge, not its destruction.” -Toni Morrison
What’s your poison? (Favorite drink.)
This is a good chance to plug my fun-fact-about-myself: I am a teetotaler. (For no particular reason. I like to tell people teetotalism is my way of distracting folks from my other vices.)
What’s your top tip or advice for APA members reading this?
There is real payoff in being extremely good at something, to the point where there are maybe just a dozen people in the world who can do the same, however minute that thing may have seemed in the first place. Just don’t forget to let people know about it!
This section of the APA Blog is designed to get to know our fellow philosophers a little better. We’re including profiles of APA members that spotlight what captures their interest not only inside the office, but also outside of it. We’d love for you to be a part of it, so please contact us via the interview nomination form here to nominate yourself or a friend.
Jessica Castellani
Jessica Castellani had a unique high school experience attending Toledo School for the Arts, where she played in a percussion ensemble and steel drum band for six years. She earned her dual Bachelor of Arts degree in Psychology and Religious Studies from the University of Toledo. Her primary focus was ‘the Self’ and the mystical experience of losing it. She earned her Master of Art in Philosophy from the University of Toledo as well, with a specialization in Comparative Philosophy, Eastern Studies, and Continental Philosophy. She has taught World Religions and Introduction to Philosophy at The University of Toledo both in person and virtually. She is a member of the Buddhist Temple of Toledo, tutors students, and has worked in the service industry for over a decade. In her free time likes to spend time outside and with her pets, friends, and family.
