What was your motivation for writing about L S Lowry?
I used to cycle around Manchester as a child and so I became imbued with Lowry's material. Despite leaving Manchester and moving to London, I kept my contacts and visited and revisited Manchester, Stockport and Salford, soaking it all up long before I became a critic or an art historian.
Over the years, I developed a great enthusiasm for Lowry. This was helped by doing extensive radio interviews with him in the 1960s. That was how I got to know him.
So, your new book about Lowry is the fruit of a lifetime's obsession?
It's a lifetime interest that eventually became obsessive. I got really fed up of the contempt that the art establishment expressed for Lowry.
When he died in 1976 the Royal Academy put on a retrospective show and it was, at that time, the biggest audience the RA had ever had. There should have been another show in the intervening 30 years - it would have been a gold mine. But various people in the establishment - my unrelated namesake Norman at the Royal Academy, for instance - had the power to set up another retrospective and didn't. That there were no Lowrys on display at Tate Britain struck me as so grotesque that I thought I should try to make an effort to improve the situation.
The art establishment often dismisses Lowry's technique as crude.
If you talk to any auctioneer or art dealer, he recently will have been offered a newly discovered Lowry, found in an attic. In nine cases out of ten it's a fake. He is faked because he looks simple, but he isn't simple. The compositions are immensely subtle. They are a mixture of topographical reality and Lowry's imagination, and no one else has an imagination like Lowry, so the forgers give themselves away - unless they're actually copying an existing painting and hoping that no one will notice.
Why was he so convinced that the industrial landscapes he painted possessed beauty?
They did, but you had to be able to see it. You had to not be put off that all the public buildings were blackened by soot. If you go to Manchester today and look at the town hall and the central library, which have been scrubbed clean, you can see their classical Victorian beauty. Lowry saw the beauty of Manchester and Salford from the beginning.
You insist in the book that he had no political motivation in depicting factories and slums.
He certainly had great sympathy for those who lived in appalling circumstances, and his individual paintings of human beings are very clear on this point. Whenever you see a well-dressed man with a briefcase and an umbrella in a Lowry painting you know this person is being mocked. He doesn't mock the poor.
But his political views were conservative with both a small and a large c - partly because he hated taxation. When he couldn't rub two pennies together, that didn't matter, but as he became successful, and as we moved into a period in which it was possible to pay 19 shillings and sixpence in the pound in income tax, he became rather vituperative towards both Conservative and Labour governments.
Why did Lowry stop painting industrial scenes in the early 1950s?
He got fed up with painting the industrial pictures and wasn't sure that people understood them. It was a self-conscious decision whose motivation was primarily boredom. If you keep on painting the same kind of picture and you're very prolific, there must come a time, if you're a great artist and you understand what you're doing, when you say: "Right, I've done it all now and there's no point in doing any more. I know people are queuing up to buy them and that's very nice for them, but it's not nice for me."
He deliberately made a switch, and it had a remarkable effect on his work. A lot of his supporters just fell away, and he was in despair - he had a houseful of paintings that no one wanted. Then a businessman named Monty Bloom started buying multiple portraits and Lowry was happy again and stayed that way. Bloom's enthusiasm spread and the later paintings began to sell, and rightly so. l
Interview by Jonathan Derbyshire