Back in October 2007, way back when the first generation iPhone was still a hot commodity

and the stock market was at an all-time high before the Great Recession,

Terence Tao, a professor of math at UCLA, was determined to answer a question that had long been

debated among mathematicians. What exactly is good mathematics? Is it about rigor, elegance,

real-world utility?

Terry wrote a very thoughtful and generous, I would even say open-hearted essay,

about all the ways that math could be good.

But now, more than 15 years later, do we need to rethink what good mathematics is?

I'm Steve Strogetz, and this is the joy of why, a podcast from Quantum Magazine,

where my co-host, Janelle Levin, and I take turns exploring some of the biggest

unanswered questions in math and science today.

Here today to revisit the eternal question of what makes math good is Terry Tao himself.

Professor Tao has authored more than 300 research papers on an amazingly wide swath of mathematics,

including harmonic analysis, partial differential equations, combinatorics, number theory, data science, random matrices, and much more.

He's been referred to as the Mozart of Mathematics.

And as the winner of a Fields Medal, a breakthrough prize in mathematics, a MacArthur Fellowship,

and many other awards, that moniker is certainly well-deserved.

Terry, welcome to the joy of why.

I'm very excited to be able to talk to you about this question of what it is that makes some types of mathematical research good.

I can remember pretty vividly flipping through the bulletin of American Math Society back in 2007 and coming across your essay about this issue that you posed for us. It's something that all mathematicians think about. But for people out there who may not be so familiar, could you tell us how did you land on this question? How did you define good math back at the time?

Right. Yes. It was actually a solicitation. So the editor of the bulletin at the time had asked me to contribute an article.

I think I had a very naive idea of what mathematics was as a student. I kind of had this idea that there was some sort of

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