ROBERT PIRSIG has a bone to pick with philosophers. As his era-defining memoir Zen and the Art of Motorcycle Maintenance levitated up the bestseller lists in 1974, all he heard from them was grumbling.

This story of a father-son motorcycle trip across America was just a skeleton of a philosophy, they said. What exactly was this “metaphysics of quality” he kept talking about? And who was he to tell them about it? Seventeen years later Pirsig gave his answer and it came in the form of a 500-page novel, Lila: An Inquiry into Morals. Now, at last, the thinkers of the world had something to tinker with. Their response? “Silence. They have just given me zero support and great hostility,” Pirsig says on the eve of the novel’s reissue in Britain.

“It’s just they don’t say anything.” Now, Pirsig believes that he has one last shot at explaining his philosophy to the public, and if it means coming out of seclusion, so be it.

Sitting in a hotel suite that overlooks the Charles River in Boston, a meditation mat at his feet, his wife Wendy at his side, America’s second- most reclusive New England novelist does not appear to have sweated much over his celebrity.

At the age of 77, Pirsig is a white-haired, bandy-legged old coot, as they say in this country. Years at sea and on the road have given his face a sun-blasted quality. His voice is strong and clear, but when he takes out a pen and paper to demonstrate a concept, his hands shake.

“As I see these two books,” Pirsig says, drawing an oval on a notepad, “there is a Zen circle. You start here with Zen,” he says, marking an X, “and then you go here to enlightenment, that’s what’s called 180 Zen.

“Then you go back to where you started from — that’s 360 Zen — and the world is exactly as it was when you left it.” Pirsig sits back and lets that sink in, then adds: “Well, I felt that Zen and the Art of Motorcycle Maintenance was the journey out, and Lila was this trip back.”

This might explain why Lila was not as universally adored as its predecessor. Zen was a serious feelgood book, a modern day “Thoreau”, written by a man who had been through the wringer, but emerged having identified a better way to live.

It was also as picturesque a tour of western America as one could find between two covers. Lila is an almost noir-like novel about a writer who falls in love with a former prostitute. As they float down a brooding river toward New York City, the writer — whose name is Phaedrus, the name Pirsig gave his insane alter ego in Zen — muses on her nature and on the metaphysics of quality (MOQ).

The novel is structured like a river with many locks — each stage a new level of Pirsig’s philosophy. The mental work it takes to measure these ideas explains why Lila has sold 600,000 copies, hardly a failure, but nowhere near the 4-6 million Zen.

There are two types of Quality, as Pirsig sees it, Dynamic and Static.

“Without dynamic quality an organism cannot grow,” he explained in an essay. “But without static quality an organism cannot last.”

While it became a cultural cliché to say that we have moved beyond good and evil, Pirsig believes just the opposite — and he believes that the MOQ can be a useful tool in bringing order to a chaotic world.

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