Sometimes we get sad about things and we don't like to tell other people that we are sad about them. We like to keep it a secret. Or sometimes, we are sad but we really don't know why we are sad, so we say we aren't sad but we really are.

You make a film you feel is as real as possible and hope people react as though it were real.

I am atheist in a very religious mould. I'm always asking myself the big questions. Where did we come from? Is there a meaning to all of this? I read the King James Bible, as all English writers should. And when I find myself in church, I edit the hymns as I sing them.

And when you look at the sky you know you are looking at stars which are hundreds and thousands of light-years away from you. And some of the stars don’t even exist anymore because their light has taken so long to get to us that they are already dead, or they have exploded and collapsed into red dwarfs. And that makes you seem very small, and if you have difficult things in you life it is nice to think that they are what is called negligible, which means they are so small you don’t have to take them into account when you are calculating something.

I started writing books for children because I could illustrate them myself and because, in my innocence, I thought they'd be easier.

As a teenager, I was always this strange mixture of kind of vice-captain of the rugby team and sensitive artist type the rest of the time. I was sent away to this public school in the middle of nowhere, and I think we managed to completely miss out on normal youth culture.

And it occurred to him that there were two parts to being a better person. One part was thinking about other people. The other part was not giving a toss what other people thought.