26-04-2025
Is HANNAH FRY the cleverest woman on TV? From taking over Stephen Fry's Cambridge turrets to cracking the dating app code
If there was a prize for being the smartest person on the box, Hannah Fry, 41, would surely be the frontrunner. In November she was appointed the first Professor of the Public Understanding of Mathematics at Cambridge University and is president of the Institute of Mathematics. She presents numerous popular science TV and radio shows and has one million followers on Instagram, where she posts scientific explainers. But if it was a contest between her and Stephen Fry, who would win? 'We're very different sorts of clever,' she says, sitting opposite me wearing a green corduroy jumpsuit and never quite getting around to eating her lemon drizzle cake. They do, however, share more than a surname. 'I have his old room at Cambridge. It's got two turrets, which I think is very Stephen Fry. Although I've genuinely spent about 25 minutes in that room because I just find it very intimidating.'
Fry's mission is not to make the complicated simple but to bring to our attention the scientific marvels and stories that surround us. Her latest project is the third series of The Secret Genius of Modern Life, which has just aired on BBC Two. In it Fry disassembles – sometimes violently – domestic items in order to illustrate how they work. In one episode she hacks at the back of a fridge, in another she melts a credit card in a glass of nail varnish remover. It's mesmerising viewing, made even more so by Fry's inexhaustible charisma and everywoman appeal.
Fry grew up, the middle of three sisters, in Ware, Hertfordshire, and attended an all-girls state secondary school. Neither of her parents went to university. Her father worked in a factory making hydraulic lifts for trucks and her mother, who had come to London from her native Ireland in the 1970s, was a part-time teaching assistant who pushed her daughters academically. 'She was just like, 'Life is suffering, so crack on with it',' says Fry.
While working as a lecturer at the UCL Centre for Advanced Spatial Analysis, Fry was asked to fill in at a science stand-up comedy night. 'It was terrifying,' she says. 'But I'd always rather try something and it not go that well than not do it at all. It's a maths idea – regret minimisation. You imagine yourself in a few years' time, looking back, and choose the path that you think you'll regret the least.'
It was this decision-making strategy that compelled Fry to deliver a Ted Talk called 'The Mathematics of Love' in 2014, about dating, statistics and finding the perfect match. It has since been viewed more than five million times. As a result of this success the public engagement gigs rolled in.
She was commissioned to write the book version of her Ted Talk while on honeymoon in 2014, having married Phil Lythell, a sports writer, the year before. The couple have two daughters, who are now five and eight.
Fry's frenetic teaching and broadcasting schedule meant that Lythell was the stay-at-home parent. 'That was always the way it was going to work for us,' she says. 'It made sense financially.'
Of course, there were barriers that Fry surmounted along the way, such as the endemic sexism in her field. 'When I was younger, professors were all male and there were numerous situations where people thought that I wasn't as good as I actually was. But the flip side of this is one of the most glorious things ever, because if people think you're not capable, it's like being able to speak a language when people don't realise that you can speak it. There have been times I've been at a conference and people have written me off. Then it's just so much fun to drop in a little sentence that shocks them.'
Likewise, she experienced class-based prejudice. 'There were references that people used, expectations that people had. You have to be cautious, not to give yourself away.' She is less concerned about this now, even though her new position at Cambridge means she has found herself in some confounding scenarios. 'I went for a dinner and it was literally like that scene in Titanic where they can't work out what the cutlery is for. There were six glasses on the table. It was ridiculous.'
As a result of being an outsider, Fry found it harder to turn down the many opportunities that came her way – until life intervened and forced her to pause. In 2021, at 36, following an abnormal smear test, she was diagnosed with cervical cancer and underwent a radical hysterectomy. She documented this in the extraordinary 2022 Horizon programme, Making Sense of Cancer With Hannah Fry. This examined statistical data around diagnosis and treatment, as well as offering a vividly intimate video diary of Fry's experience, including the moment she bursts into tears when telling her husband that she has the all-clear.
Fry's procedure involved removing her womb and much of the surrounding tissue, including her lymph nodes, and as a result she developed lymphoedema, a condition that causes limbs to swell. She had an operation to minimise the impact of this and also feels fortunate that she was able to keep her ovaries – 'they took basically everything else' – and so did not have to go into early menopause.
It was in the aftermath of this experience that Fry, who introduced us to the 'mathematics' of love, divorced her husband. And while her formula didn't lead her to lasting happiness,
Fry has discovered the next best thing: a great divorce.
'My ex is genuinely one of life's good people, but we were never a good match, we're just too different.' They live three doors down from each other in South London and share looking after their daughters. 'We are still incredibly good friends. I don't like to brag but I think I might have the best divorce of all time. He was over at my house watching Gladiators with the kids on Saturday night.'
A return to single life offered Fry the opportunity to do some rigorous data analysis of dating apps. Initially she found herself booted off Hinge because the app thought she was someone pretending to be Hannah Fry.
So she made a new profile, and then a few more, to game the system and get linked with the most eligible matches.
Fry is now writing a book about uncertainty. 'Everybody struggles with it. All of us know, deep down, that certainty is impossible. But we like to trick ourselves into believing that there are answers out there.' She is also now on series 22 of her Radio 4 show Curious Cases, is working on a new series for National Geographic, and will soon return to teaching. She has a better understanding than most of the impact that AI might have on the world in which her daughters will grow up. She has been presenting the Google DeepMind podcast since 2019, for which she has frequently interviewed the founder of the DeepMind AI research lab, Demis Hassabis. 'What's changed in the past two years is that AI has a conceptual understanding of our world in a way that it didn't before,' she says. 'It can do creativity now.' I ask if this scares her. 'No. We do have to be very careful and there are genuine legitimate existential dangers on the horizon, but I also think that there is a potential version of the future that is exciting.'
Fry is a natural optimist, and part of the pleasure of being in her company, of watching her on television, of listening to her on the radio, of engaging with her on all her many platforms, is that she is able to make the world seem like a less scary, more interesting place. The only problem is there is not enough time for her to do all the projects she is interested in. 'There has been talk of cloning me,' she says. Now that would make good science TV.
Stylist: Joanne M Kennedy.
Hair: Alex Szabo at Carol Hayes.
