I'm Rory Stewart and I grew up wanting to be a hero and I'm still fascinated by the ideas of heroism.

In my new series, I'm taking in the long sweep of history from Achilles to Zelensky and asking, what is a hero?

Simply doing your job, being a decent human being.

A true hero is someone who just kind of shines by

their own light and that light is to be recognised by others. The Long History of Heroism with me,

Rory Stewart. Listen on BBC Sounds. This is Discovery from the BBC World Service. I'm Jimal

Kalili and in my series The Life Scientific,

I get to talk to some of the extraordinary men and women who are trying to understand our

world and make it a better place. And my guest today likes to solve real world problems.

You can use mathematics to model virtually anything, he says.

Naira Chamberlain is president of the Institute of Mathematics and its applications and principal mathematical modeler for multinational

engineering company, SNC Lavalin Atkins. He specialises in complex engineering and industrial

problems, creating mathematical models to describe a particular feature or

process, and then running simulations to better understand it and predict its behaviour.

Nara is one of just a handful of esteemed mathematicians featured in Britain's book of prominent

people, Who's Who, and the first black mathematician. Since 2018, he's featured on the black power list,

celebrating the UK's top 100 most influential people of African or African Caribbean heritage.

When he first made the list, he was particularly proud to rank higher than Stormsy and Lewis Hamilton,

though his motto for life does, in fact, come from his childhood sporting hero,

Muhammad Ali, with a mathematical twist, of course, float like a butterfly, sting like a mathematician.

Mara Chamberlain, welcome to the life scientific. Thank you very much indeed. It's good to be here.

So tell me, what did you mean by sting like a mathematician?

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