Most adults, unlike most children, understand the difference between a book that will hold them spellbound for a rainy Sunday afternoon and a book that will put them in touch with a part of themselves they didn't even know existed.

And I know I can do this because I went to London on my own, and because I solved the mystery…and I was brave and I wrote a book and that means I can do anything.

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.

But in life you have to take lots of decisions and if you don't take decisions you would never do anything because you would spend all your time choosing between things you could do. So it is good to have a reason why you hate some things and you like others.

Being clever was when you looked at how things were and used the evidence to work out something new.

I think I've learnt that there is no character so strange that you haven't shared their experience in some small way.

There's something rather wonderful about the fact that Oxford is a very small city that contains most of the cultural and metropolitan facilities you could want, in terms of bookshops, theatre, cinema, conversation. But it's near enough to London to get here in an hour, and it's near enough to huge open spaces without which I would go insane.