One particular aspect of Siddhartha’s revelation of the outside world has always struck me. Quite possibly he lived his first thirty years without any knowledge of number. How must he have felt, then, to see crowds of people mingling in the streets? Before that day he would not have believed that so many people existed in all the world. And what wonder it must have been to discover flocks of birds, and piles of stones, leaves on trees and blades of grass! To suddenly realise that, his whole life long, he had been kept at arm’s length from multiplicity.

When I multiply numbers together, I see two shapes. The image starts to change and evolve, and a third shape emerges. That's the answer. It's mental imagery. It's like maths without having to think.

I have tried to be more flexible, but I always end up feeling more uncomfortable. Retaining a sense of control is really important. I like to do things in my own time, and in my own style, so an office with targets and bureaucracy just wouldn't work.

I did have a very restricted, regimented life. There was a kind of happiness there, a contentment, but it was a small happiness within very clear and delineated borders.

From 'Embracing the Wide Sky', I went to the States, to Canada and to different parts of Europe as well. I gave interviews in several languages.

My algebra was relatively poor. I found it very difficult to use equations that substituted numbers - to which I had a synesthetic and emotional response - for letters, to which I had none. It was because of this that I decided not to continue math at Advanced level, but chose to study history, French and German instead.

There is no such thing as an average person. They really are guidelines for people to grapple with the unknown, and we can always surprise expectations.