This script is an adaptation of the story and not a biographical picture. Was that a challenge for you as a screenwriter, to boil it down to what's really important?

When I went to Brian (Grazer) and said I don't really understand what a "Bio Pic" is. Because what you do in that kind of picture is that you take four or five poignant moments from someone's life and then you turn it and you have an emotional experience and you suggest that that's the truth of someone's life. Of course, it's not.

So, I said what I'd like to do is do something inspired by his life using the architecture God gave him which is genius followed by madness followed by a Nobel Prize, which is pretty extraordinary storytelling architecture, and then hang evocative experiences off of that.

How often did you speak to John Nash when writing this screenplay?

I spoke to him only after I wrote it. I was really trying to build this idea of what it's like to have half your world taken from you.

Part of what the story seems to say is that he used the power of his mind to overcome the illness.

John believes that he got better through the power of his mind. I don't know anyone who thinks you can think your way out of schizophrenia except John. And I don't think anyone really knows why people do or don't get better. I think the movie tries to say that however you get better - which is why the John in the movie is still on medication - is probably a combination of many things.

Were the delusions Nash experiences in the film your inventions and creations or were they things that Nash told you he'd gone through?

They were things I created to convey the experience of mental illness. I tried to craft a delusional system that seemed real and whole so that the audience would have a sense

what it would feel like for someone with this mental illness. The feelings of a schizophrenic are that these things are real but this is a metaphor not a strict portrayal of what life is like for someone who has this mental illness.

You've mentioned that you grew up around children with mental illness. How did that take place and how did it influence your work on this project?

One of the first homes for emotionally disturbed children was in my house. My mom is a shrink and my dad is a therapist and I'm a writer. And so all these kids were in my house. I lived with people who had schizophrenia long before I knew a name for it.

Was it a strange transition to go from your house to school every day?

Not really. It was all I ever knew.

Did you go to your mother with the script for advice and what did she think of the final work?

Well, she's my mother so she loves it. But I don't claim to be an expert on mental health - certainly not my own - and I took it to a lot of people for feedback and advice.

You've worked a lot with Joel Schumacher. Do you have any plans to work with him again?

Not right now but there may very well be. He continues to be a great friend and is someone without whom I'd probably wouldn't have a career. He just sort of plucked me out. I never had anything made before I wrote "The Client."

What's next? Have you finished the adaptation of "Memoirs of a Geisha" yet?

I should be writing it now. If Steven (Spielberg) finds out I'm here I'm going to be in trouble!

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