The critic and author said there was a "lack of intellectual ambition" and said there was a growing audience for more intelligent programming.

Bragg, 60, who is controller of arts at London Weekend Television, said more programmes like Lord Winston's acclaimed BBC One documentary The Human Body should be made, and that respectable viewing figures for his own South Bank Show on ITV bore out his theory.

Pop pal: Bragg with singer Geri Halliwell

He said: "Sometimes I am baffled by the lack of intellectual ambition in British television.

"Am I alone in feeling that there is not so much a dumbing down as a failure to engage at the highest level?"

Observing that the "passion for the ironic" was "collapsing into the moronic", he said: "British television is still led by some extremely able people, and yet at times they can seem like thoroughbreds happy to pull milk carts.

"Am I alone in believing that here, as elsewhere, trash TV is welcomed because there are those in the opinion-forming seats who still feel that all TV is trash, and all proofs to that absurd theory are welcome?"

Speaking at the launch of LWT's new arts and features line-up, he pointed out that a South Bank Show on poet Tony Harrison had an audience of 1.5 million - equal to the sales of The Sunday Times, or three times that of The Guardian.

Paul Merton: Featured in the new series of the South Bank Show

With more university students, a rise in broadsheet newspaper sales and literary festivals becoming more popular. He said there was a big audience "ready to follow intelligence onward and upward".

"We are all, although we seem to hate to admit it, getting less dumb".

Among the personalities featured in forthcoming editions of The South Bank Show are pop band Blur, flautist James Galway, comedian Paul Merton, Disney's musical The Lion King, Cher, Yoko Ono and Michael Douglas.

Other LWT arts highlights include a programme on the Ten Commandments and a history of the British hit single.