By the time I came to do the final ones [Harry Potter's film], I was working on something that was massively successful. There was a huge difference in indulgence and all sorts of stuff. A very big difference in peoples' attitudes. They were very pleased with themselves. In human terms, it was quite interesting to see the difference.

The most difficult thing about painting is the self-discipline. When I finish a job, I give myself a few days, but then I have to discipline myself quite fiercely if I want to do some painting that's worthwhile. Otherwise, you're just doodling. It's much easier when you're just told what you have to do.

If I hadn't been a part of [Harry Potter] I would have been deeply upset.

What I like about [Berthold] Brecht, it's very interesting. When Helene Weigel came over and somebody talked about Lotte Lenya and said "well, she wasn't alienating." And Weigel said "No, no, no. Why, Lotte Lenya was so true - who cares?" She said: "Berti only developed the theory of alienation in order to stop bad acting." I heard her say that. Now that's brilliant.

I felt, you know, body and soul, as it were. But, of course, I mean, I - at that age, I didn't think in terms of being professional. I didn't know anything about it. That happened later.

Society is constantly recalibrating, redefining what it considers to be moral and immoral.

The only concession you can make is to what you believe is right.