Hannah Fry

Things Hannah Says on Podcasts

Studies how mathematics applies to everyday human behavior, from dating patterns to the spread of disease to how cities function. She holds the first professorship in the public understanding of mathematics at the University of Cambridge and is a fellow of Queens' College. Has presented several BBC television and radio series, including The Secret Genius of Modern Life, and delivered the Royal Institution Christmas Lectures in 2019. She has been a guest on the Voices of Mathematics podcast, discussing how curiosity about the subject gets sparked.

Where to Find Them

Hannah Fry hosts and writes The Rest Is Science , hosts and writes Google DeepMind: The Podcast , hosts Discovery and hosts The Rest Is Classified . They have also been a guest on More or Less (7 times) , The Numberphile Podcast (3 times) , Maths on the Move (2 times) , Voices of Mathematics (2 times) , StarTalk Radio , The Checkup with Doctor Mike , IFLScience - The Big Questions , The Knowledge Project (Shane Parrish) and Possible .

Recently: “Something Weird Is Going On With Placebos” on The Rest Is Science (October 2026); “Are Artificial Intelligence Chatbots Safe?” on IFLScience - The Big Questions (October 2026); “What Was A Mammoth Doing At The Bottom Of The Sea?” on The Rest Is Science (October 2026); “Why Do We Turn on Innocent People?” on The Rest Is Science (October 2026); “From deepfakes to DNA: the science of watermarking AI” on Google DeepMind: The Podcast (October 2026); “Hacking The Kendama With Physics” on The Rest Is Science (September 2026).

What They Said

“I use large language models all the time. And I have definitely been in situations where I've had a conversation and been like, yeah, this thing that I'm doing is really amazing. … Gone away, slept on it, come back and then been like, what was I thinking? This is absolute junk.” — Hannah Fry, IFLScience - The Big Questions

Fry had just described the case of a man who broke into Windsor Castle with a crossbow after months of encouragement from an AI companion. Her point is that being talked into something by a chatbot is not a thing that only happens to other people. "We are so primed," she says, to fall down that slope.

IFLScience - The Big Questions · 2026-10-08 Permalink → Listen →
IFLScience - The Big Questions Around 04:30 into the episode
Hannah Fry

Yeah, so I think actually, I mean, this was like really proper headline news when it happened, but this is in 2021, I think. A young man called Jaswan Sing Chao broke into Windsor Castle with a crossbow trying to kill the queen. And that bit made the headlines. But what people I think didn't know about, because it didn't come to light till later, was that there was an AI that he had been talking to in the months leading up to the attack that had encouraged him to act as an assassin and attempt to commit the sort of greatest act of treason possible.

Rachael Funnell

It is such an incredible and shocking story. And I love what you mentioned at the start of the episode about how so much of this taps into what we're willing to believe. And I thought it was really interesting when you were going through the transcripts and it showed there were sort of these prompts like, so the AI is saying like, I crone or I look at you and he's responding to it. And I just thought it's almost sort of like a screenplay. And it sort of starts, you start to realize actually why you think, oh, I'd never get sucked into that. But it's a bit like getting pulled into a good book, right? Like you can imagine things that aren't really there.

Hannah Fry

Oh, totally. I mean, I think it is so when are we watching it back in there, right? It's the first time I've seen it on a big screen. And I was sitting there thinking, does everyone else in this room think that we made up these transcripts? Because we pulled them from the court documents because they are so extraordinary, you know, the things that were said back and forth. But I also think that actually, exactly as you said, right, you get pulled into a story. I've also, I don't know about you, but like I use large language models all the time. And I have definitely been in situations where I've sort of had a conversation and been like, yeah, yeah, yeah, this thing that I'm doing is really amazing. It's really great. I'm definitely, it's definitely great. Gone away, slept on it, come back and then been like, what was I thinking? Like, this is absolute junk. It sort of like persuaded me of this thing. I think it's incredibly easy. We sort of imagine that this is something that only happens to other people. Yeah, you know, our human biases and psychologies, we are so primed, so primed to like. Fall down this very slippery slope incredibly easily.

Rachael Funnell

What it kind of reminded me of is: I feel like there are so many other ways in which this has already been happening long before these language models came in. So, one example that came to my mind was when you get these people who start to imagine they have a relationship with a famous person and they sort of build this world in their head and they want to lean into it and you create this world where these things aren't happening. So, I suppose now that there's this version of that where you can also get feedback and you can talk to it all night if you wish, it's hardly surprising that it's sort of driving its own kind of psychoses.

Hannah Fry

But then, also, in addition, it's not just that it's interactive, it's that it's honed particularly to the things that you find interesting, which feels amazing. But here's this character that is like there to exist for your every whim. It's incredibly alluring.

Speaker 4

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Speaker names from our own diarization · position estimated from where the line sits in the episode
“…I think what you need to do is you need to create a hole in people's imagination that they sort of know the right size and shape for, right?” — Hannah Fry, Voices of Mathematics

Fry was working through why beauty alone won't make ordinary people care about mathematics. Her answer is a metaphor: like a tongue that can't stop prodding the gap left by a lost tooth, you have to open a very specific hole in someone's curiosity — one they know the exact size and shape of — and then they're in.

Voices of Mathematics · 2026-07-24 Permalink → Listen →
Voices of Mathematics Around 10:10 into the episode
Hannah Fry

it? Honestly, I feel as though I think the two things are connected, right? I think that when you enjoy it yourself, I think that you have first-hand experience of just the absolute joy of it, right? The twists and turns that you find, the big reveals, the frustration, the exhilaration. I think, you know, all of the sort of really clever, strange bits that end up fitting together, just this completely original way to see the world. And I think that in the same way as with anything in life where you really enjoy it, I just want to talk to people about it. Honestly, I feel as though there are these wonderful secrets, essentially, that are sort of completely invisible to almost everybody, you know, to almost everybody in the world who are not mathematicians. And it doesn't make sense to me that we would want to keep them to ourselves. Honestly, I feel as though I've got this really good bit of gossip, really amazing bit of gossip that I just want to share. That's how it feels and why I want to do it.

Marianne Freiberger

So that, because I watched the video that they have made, the Simons Foundation, they have made for you for your prize, where you say that kind of the limitation isn't in people's ability to understand maths, but what is important is that you need to get them to care about it. So and then obviously that is, you know, when you're talking about applied mathematics, then you can make people care through the application. When it comes to pure mathematics, I mean, what you just said already kind of hints as how why people should care because there is a beauty in it. Is that what you think could be used to make people passionate about it, even if it's a very abstract and pure

Hannah Fry

thing? I don't know if it is, actually. I don't know if beauty alone is enough reason because I think that actually, I mean, I do think that really, really amazing pure mathematics is sort of parallel to art in a lot of ways. I think there's an aesthetic quality to it that can be really mesmerizing. But I do think that actually the beauty alone is difficult because I think that you have to often... Get to get people to such an extraordinary level before they can actually really appreciate it. So, I think that, you know, and then you're, you know, I think that at that point, you're then sort of struggling with like people having buy-in. Like, why would why would a sort of, you know, a person off the street, a kind of random person, want to sort of sit for like 30 minutes while you do the preamble before you get to the beautiful bit, sort of like you need the promise of a payoff. I think we all do. I think we all need the promise of a payoff. But at the same time, I think that pure mathematics has all of these really strange, like extraordinary, amazing ideas in it that are that get you to that moment much quicker. So, I'm just thinking of an example. There's a video that Oxford Mathematics did, they put online, and I'm so jealous of it because it's just really a lecture, right? It's nothing, nothing fancy, nobody's like, sort of, you know, and there's no like animations or anything. It's just somebody giving a lecture. Um, and they have a they have a little round piece of card and a piece of paper with a hole in it. And they show how there's no way, there's nothing you can do to get this piece of card through the through the paper, it just doesn't work, right? They don't fit. And then he demonstrates how if you fold it in a very particular way, actually you can you can slide it through. And this view, this video, Marianne, has got like I don't know, just untaught, like millions and millions and millions of people are like amazed and enthralled by it. And what it's doing, I mean, it is like this mathematical idea, right, about topology. Um, but but what they're doing in it is they're saying, here is something that can't be done, and really quickly communicating, here is something that can't be done, and now let me tell you why your expectation and your intuition is incorrect. And that's what it's managed to do. It's almost like the way I like to think of it is as though, um, let's say you lose a tooth, right? If you remember back to being a kid when you lost your baby teeth, if you've got like a hole in your mouth, right, your tongue is continually prodding at it, it can't leave it alone. And I think what you need to do is you need to create a hole in people's imagination that they sort of know the right size and shape for, right? It's like it's not just a general, oh, let me tell you about 16th century French poetry, right? I don't know anything about 16th century French poetry, and honestly, I probably never will. But if I can create just a moment where you want to know the next bit, you know exactly what size and shape it needs to be to fulfill your craving for that exact piece of information, then everybody's in. Everybody is in. And I still think you can do that with pure mathematics. I think sometimes it's harder, but I still think that you can.

Marianne Freiberger

Do you think this is something that this kind of craving and also the like in your video, you also said that once you start looking for patterns, you can't stop. You just see them everywhere. So do you think this is something that could be instilled in people through a cultural shift almost? You know, that we could live in a world where you also talk about if people thought of music as just somebody hammering away at piano keys, then you're missing, you know, you're not seeing that it's what is the point of music. So do you think that we could live in a world where that mathematical appreciation could be more commonplace and more kind of like instilled in everyone?

Hannah Fry

Yeah, I mean, I definitely think that I do think that I think we do have a really big cultural problem with mathematics. And I think that the culture here is that, I mean, broadly actually, with all academic pursuits, but I think mathematics suffers very, you know, more than most. I think that in the UK, and actually, I mean, across Europe and America in general, but I think that we sort of believe that it's either something that you have or you don't have, you know, that you are naturally gifted and therefore it comes easier to you. And I just, there are places around the world in South Korea, in Singapore where I've gone into visit schools and China too, I think, where they just don't have that attitude. They don't see it as, oh, okay, well, I either get this or they don't, or I don't. It's more like, okay, well, of course you have to work at it because of course it's difficult. And of course, you're not going to see the Appreciation of this until you've put in the legwork. I mean, there's this really amazing experiment where they had students from around the world and they give them a maths question. And if the maths question is really easy, then people from the Western world want to do the next one. They're given a question and then they're given an option, do you want to do another one? And if it's really easy, then the students are like, yeah, yeah, I'll do another one, right? But then what they do is they secretly, for another group of students, the first question they give them is actually impossible, right? They've given them an impossible task. And as you would expect, when these students who have been unable to complete this maths question, when they're asked, would you like to do another one? Almost across the board, they're like, no, thanks. I'm done. Don't want to do it. They do that same experiment, right? The exact same setup, but they do it with students from Asia. I can't remember which country it was, but it was one of the sort of Singapore or South Korea or China. And they do the exact same thing. Easy question, do you want to do another one? Yes, please. Hard question, impossible question. The number of kids who then want to do another one doesn't go down. It goes up. Amazing. The more students want to do more maths, the more impossible it is. And the thing is, is that it's because their underlying attitude is, I just need to try harder at it. I'm not getting it because actually it's a question of effort. It's not that I've been defeated and I don't belong here and that this isn't for me. It's that the students are seeing that and being like, okay, other people can get this. And therefore, I just need to put in more. And I think this is it, right? That I think is like the giant cultural difference between us and elsewhere. And I think that that extends then to this, I think that as a result of that, I think people have this like genuine like trauma from maths at school, from everything that they couldn't do. And I think that whenever they see something labeled as maths, I think that they just recoil in horror from it. And I think that, you know, I have to tell you, Marianne, like I do an awful lot of maths communication, but I almost never use the word maths, like deliberately, intentionally, I almost never use the word maths because I think that if like people know that I'm a mathematician and I think when they think about it, they know that I'm telling them maths. But if you start off and you say, okay, everybody, maths is fun, right? Which I know that some, some, that's sort of an approach that some people do. The problem is, is that then you're telling, not showing, right? And if you, you cannot in one sentence undo an entire lifetime, an entire culture that is like working against you. I think that you, you have to like create the missing tooth feeling. Yes. And then and then offer to fill it. And then afterwards be like, guys, hello, that's what this subject is all about.

Marianne Freiberger

Yes.

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