Marcus du Sautoy, Professor for the Public Understanding of **Science** at Oxford University, and **guest speaker** at the **Hay Festival**, writes in the Telegraph Online, “A mathematician is like a painter or a poet – a maker of patterns.”

““**Du Sautoy**. See me after the class” bellowed my maths teacher. I was terrified. I was 13. I thought I was in trouble. At the end of the lesson Mr Bailson led me round the back of the maths block. My terror mounted. I’m really in trouble now. But then he got out his breaktime cigar and said: “Du Sautoy, I think you should find out what maths is really about.” Maths he declared wasn’t about long division and percentages: it was something much more exciting.

“He recommended some books to open up this hidden world. That weekend I went with my father to Oxford and bought the books. One of them was a slim volume by G H Hardy called A Mathematician’s Apology.

“Instead of being filled with equations Hardy, who taught at Cambridge, spends the book laying out his manifesto: “a mathematician , like a painter or a poet, is a maker of patterns. The mathematician’s patterns, like the painter’s or the poet’s, must be beautiful; the ideas, like the colours or the words must fit together in a harmonious way.”

“At the age of 13, I was already torn between the two camps of art and science that the education system seemed to mark out. I had just started learning the trumpet and neomg thrilled by theatre. But I had also been bitten by the science bug. Hardy’s book opened up a bridge between these two cultures: mathematics.

“The book does contain some mathematics: two proofs of theorems that capture the beauty that Hardy talked about. There is a proof of the fact that there are infinitely many prime numbers. A second proof shows why the square root of two can’t be written as a fraction. Both were discovered by the Ancient Greeks yet are as true today as they were 2000 years ago. As an insecure teenager, the certainty that mathematical proof provided was very attractive. But I was also struck by the power of clever thinking to capture something as mindblowing as infinity.

“Another important part of the book is the foreword written by Hardy’s friend CP Snow, in he which tells the extraordinary story of Hardy’s collaboration with the Indian mathematician Srinivasa Ramanujan. One morning early in 1913, Hardy “found among the letters on his breakfast table, a large untidy envelope decorated with Indian stamps. When he opened it, he found sheets of paper by no means fresh, on which, in a non-English holography, were line after line of symbols.” At first Hardy dismissed the letter as the work of crank but by the evening he had changed his mind. “The writer of these manuscripts was a man of genius.” So began one of the most romantic mathematical collaborations in history.

“I am not the only one to have been fired up by both Hardy’s Apology and Snow’s account of Hardy’s collaboration with Ramanujan. Complicite’s Simon McBurney contacted me in the summer of 2006 to say that the same book was to be the inspiration for a new play he was devising. So began our own collaboration that would culminate in the award-winning play, A

“Disappearing Number, not just about extraordinary mathematicians but which has mathematics at its heart.

“I still have my copy of Hardy. Like a magic key, it was responsible for unlocking the secret garden of mathematics. Thanks to that book I discovered that mathematics is full of beauty and emotion, drama and jeopardy. It’s the book that sparked my dream to become a mathematician like Hardy.”

Copyright Speakers Corner 2017