So here is my report. Quentin Blake is surprisingly quiet, but with a sense of humour that sneaks up on you. He is shortish, with lively eyes and is thoughtful, eccentric, precise. I'm not sure where he stores his ego in his airy studio overlooking a square in London's Earl's Court, but I couldn't find it anywhere. "Do you really think that I'm the most famous illustrator in Britain?" he asks when I mention this. He continues: "Well, I don't know. People say things like that but it's a kind of fact that is hard to take in. You know it's always a surprise when you see someone reading your book."
If that is the case, he must live a life of perpetual surprise.
What a lot of raised eyebrows that would be to draw. He has illustrated some 200 books, including all of Roald Dahl's, as well as his own, such as Mr Magnolia. He illustrates the odd book for grown-ups, too, and has just finished The Hunchback of Notre Dame for the Folio Society.
The Word, the London Festival of Literature, has begun this week and for this he has drawn the Great Word Map, a sort of ink-stained and splodged A to Z. The festival has chosen 33 novels to symbolise 33 parts of London and Blake has done a drawing for each one. The books sit in a crate at the side of his studio. He likes to read, and so already knew most of them but a few, he admits, he got through "very fast". We look at the roughs. "Editors are always saying that the roughs are always better." He says sometimes they actually use them instead of the finished ones.
It is not long before I notice that we are not alone in his studio. Propped up against the wall on his slanted desk, which is littered with jars holding hundreds of pencils and pens, is a man. Or should I say, a character. Like most of Blake's creations, he is a study in motion, though his progress must be hampered slightly by the fact he is wearing stilts. He is angular, with too-big yellow trousers and the pointiest nose. He looks like the quintessential Quentin Blake character, but I don't recognise him from the books. "Oh him," says Blake. "It's nobody. He's just somebody who lives in that drawing."
He is part of what Blake calls his "repertory company". He describes illustrating as a mixture of painting and theatre, but his heart is really with the latter. "Most people think illustration is like a version of painting but, of course, a lot of contemporary painting hasn't got that narrative element at all. It's been purged of that." He talks about painters like Tiepolo and Tintoretto, whose works told stories and were full of drama. "What would they do now? They'd probably be in the movies, wouldn't they? You'd need that to get that sweep, those dramatic moments. Illustration now is probably a rather small version of that narrative theatre."
He rarely draws a picture without a person in it. "Yes that's true. I mean, animals count as people, don't they? Yes. I think so. Animals are people too." He returns to his comparison with the theatre. Some people like scenery, others a bare stage with props. Quentin Blake likes the latter. His work is full of props - wonky stoves and skew-whiff pans - but rarely does he paint the scenery. It helps create the Polaroid effect, that feeling of capturing a moment.
This is a quality he admires in painters, too. "I like Goya very much, because one of the things you get there is this kind of instant quality, although they look as though they are going to be there forever. I don't know how he does that." He mentions Picasso and Degas. "I think Degas has come back having been unfashionable, rather in the way Dickens came back. People are coming to realise that you can do it like that. He was a wonderful draughtsman, absolutely wonderful. You just love the way he does the line. You can feel it. Have you seen the ones of the brothels? That is a kind of illustration style he had. He did his paintings, but then he did these little pictures. They are more little instants, little moments. They are improvised."
Quentin Blake is 66 now, and has been drawing ever since he can remember. He grew up in south London. His father was a civil servant, his mother a housewife. At 14, he started sending cartoons to Punch. He cringes to think of it now. "They really were lacking in taste." This went on for two years. How many? "I seem to remember it was about 70," he says. "Then I sent them a plaintive note asking to come and see them."
He went up to the Punch offices which, he says, in those days were rather grand, like a London club or something. He was put in waiting-room, next to a large woman, and given a copy of The New Yorker, which he thoroughly enjoyed. Then he sat, and sat, and sat. "After quite a long time, the secretary appeared and asked what I was doing there. They had thought I was the woman's nephew. And by then it was too late to see the art director! But I did go back. And then he bought two of my drawings. They weren't that big. Tiny, really."
At Cambridge, he studied English but, before becoming a teacher, he decided to give his drawing a go. He went to Chelsea Art School part-time. It was pounds 7 a term. He did life-drawing. "I was in a group called the Odds and Sods, not officially, but that is what we were. A collection of grey- haired ladies, immigrants and, well, me." It sounds like a Quentin Blake drawing to me. "Then I used to go home and draw from memory and imagination. Which I've been doing ever since, actually."
He and Roald Dahl were teamed up because they had the same publisher. Quentin Blake likes illustrating because of the challenge of drawing as others write, but Dahl was intimidating. "To begin with, I can remember thinking that he is just so famous. A power. I thought he's going to change things." In fact, sometimes it was the opposite. The original BFG wore an apron and boots. Dahl didn't like the look of that, though that is what he wrote, and gave him a waistcoat instead. Then there were the feet. "One day, a rather shapeless brown-paper parcel arrived, and in it was the big sandal," says Blake. "It was one of Dahl's. It was Norwegian. And he said: `What about this?'." Now that is a footnote.
Illustrators never have to retire, and Quentin Blake doesn't see why he should. If he has a hobby, it is France, and he can draw there as well. He says that characters are something that happen when you draw. He sometimes contorts in sympathy as he is creating them, and makes faces to match theirs. So what's next? He has an idea for a new book, but after that isn't sure. "I always think that I won't have any more ideas," he says. But, I say, you've had millions of ideas. "I know, but I can't think that I am going to have any more. You do one and then you really cannot believe that you are going to have another."