Storytelling – and the taxi number

I’ve just finished reading ‘An Indian Clerk’ by David Leavitt, which is a fictionalised account of the life of Ramanujan, during the first part of the last century. He was a self-taught mathematician from India who only came to prominence after he sent some of his work to Hardy, the most eminent mathematician in Britain at the time, based at Cambridge. Hardy saw that although the way Ramanujan worked was unorthodox, he had an extraordinary feel for mathematics, and arranged for him to come and work at Cambridge.

Not many people outside the field can understand either Ramanujan’s or Hardy’s contributions to mathematics. What is more widely known is the story of the taxi number.

I first heard this story when I was a child, and my grandfather used to tell it to me;
‘Ramanujan was ill, and being cared for in a nursing home in Putney [incidentally just five minutes walk from my grandparents’ flat] and Hardy came to visit him. It was clear that Ramanujan was dying, but nobody knew why.
‘Hardy didn’t know what to say to him about his illness. Instead, he remarked that the number of the taxi which he had just travelled in was 1729, which he thought was a very boring number.
“Oh no, Hardy,” said Ramanujan. “It’s a very interesting number. It’s the smallest number which can be expressed as the sum of two cubes in two different ways.”
(1729=1³+12³=9³+10³ )

And my grandfather and I would shake our heads and smile in awe at Ramanujan’s ability to analyse numbers and expose their inner workings.

My grandfather liked telling me this story and I liked listening to him. Only after he died did I realise that the story connected us in the same way that the original incident connected Hardy and Ramanujan. My grandfather’s failing memory meant that he found it difficult to take part in our family’s conversations about our daily lives. In telling the story he found a way of relating to my life, and articulating something we shared; a love of mathematics and science. And the retelling of the story over and over again, which could be seen as a symptom of dementia, could also be seen as a way of reinforcing that connection, of trying to make it as strong as possible.

Storytelling in families can be so powerful as a way of defining relationships and identities. Can it have a downside?