KEN Dodd may try to look as though he did in the Seventies, the finger-in-socket hairstyle, the dodgy denticles and the outrageous stage outfits.

But the act has moved on. A little. The last time the comedian played the Pavilion, he told a Wife joke that didn’t sit well with the audience at all. (Despite this being a theatre not known for being nailed to the mast of political correctness.)

However, Ken judged the mood, apologised and moved on to safer ground. He may be an older man, but he’s not trapped in all the old ways.

“I still try out six new gags a night,” he offers, smiling.

“But sometimes lines hit the deck. Sometimes, it’s you, or the timing, or whether you touch a nerve.

“Some love husbands and wives jokes, but sometimes it’s the throwaway line that gets the big laughs. I tried one the other night; ‘Time is a great healer. But a terrible beautician.’”

It’s hard to keep Ken Dodd on subject. He loves to flit around subjects. Right now, he wants to know if I’m married/happy/living alone. He wants to do anything it seems but answer questions that are a little difficult.

But there’s no denying he’s a comedy legend. Does part of that come from being a Holy Grail-like crusader in search of the secret of the gag?

“Yes, yes, young man. When touring I’d go to the local libraries and look up Laughter, Humour and Jokes. I’ve now got about 10,000 books on the subject.”

He’s studied the comedy and psychology of humour and has looked for answers in Bergson, Schopenhauer, and Freud.

“I think I’ve found the answer,” he says. “I can tell you how to create a laugh.”

He digresses, slightly; “Do you know humans are the only creatures which laugh?” No, I don’t. But what’s the secret of comedy, Ken?

“I won’t go into too much detail for you (subtext: seeing as you’re unlikely to grasp my higher point) but it’s about seeing things from a different point of view. It is (grand voice) the perception of the incongruity.”

He says the words ‘perception’ and ‘incongruity’ like he were a Stephen Hawking delivering a lecture on non orthogonal boundaries in black holes. I feel like a little Diddyman.

He continues on the technique of comedy, talking of how a comic has around thirty seconds to build an audience rapport.

“You talk about them. Then you do the topical jokes, such as the Referendum. Then you get into the meat of the account.”

Doddy digresses: “Are you a posh boy?” No, Ken. “Did you have two nice parents? “No, Ken. One. But one was enough. “Well, if you’re mother’s great, look after her. She’s the only one who’ll forgive you murder.”

I tell him I’ll keep that in mind if I murder a comedian who tries to set his own agenda.

But somehow he doesn’t hear the line. Instead he bellows; “You’re just like me, then!”

Exactly like you Ken, I reflect, had I been born in Knotty Ash in 1927 so desperate for attention that I became the class clown, and by the age of twelve was sending off the coupon on the back of the Wizard for a How To . . ventriloquist kit.

Yes, we both did go to grammar school (Dodd on a scholarship) but it’s hard to think we could have been twins separated at birth even if he hadn’t given up a cub reporter’s job at the Express and joined his father’s coal business before breaking into the vaudeville circuit as a comedian in his twenties.

And of course I never sold out the Paladiium for a 42 week run in 1965, or had a string of Top Ten hits, including the million-seller, Tears.

But this is mere detail, you try to point out, grinning. And fail. You fail because he’s already moved onto to talking up his Pavilion show (And why not; he wants to sell tickets.)

“When I first played Glasgow, it was a place of fear, the pubs would close at 9.30,” he recalls, unaided.

“The drinkers would throw it back.” He pauses and his throaty voice takes on an edge. “You know, we have them here. They’re called Scousers and they’re bloody awful people, all tanked up on the booze or whatever.”

What about that first Glasgow appearance in 1954? Was he genuinely terrified, or does that story make better copy?

He doesn’t answer. What he does do it tell the old Mike and Bernie story, where Mike comes on to the Empire stage, bores the audience rigid, then Bernie appears, causing a punter to tell out; “Christ, there’s two of them. . . ”

He continues; “Anyway, I went on and said to the audience, ‘I suppose you’re wondering why I’ve sent for you.’”

That was bold, Ken. And funny. “Then one bloke shouted; ‘What a horrible sight!’ and collapsed drunk in a heap. From that point on the audience were with me.”

The comedian clearly had the daring to survive the horrible audiences. Where did it come from? “It’s always surprised me,” he says in a surprising moment of reflection. “I’m not a pushy person or aggressive at all. But inside me there’s a steel rod that keeps me up there. It’s like a gift from the heavens. It’s magic.”

It’s a lightning rod. When he stands on stage the comedian is charged with enough electricity to run for four hour stretches. Is it because he is where he needs to be? “Yes, the truth is I love it. I am completely stage struck.”

Bob Monkhouse once said that for Dodd, everything off stage was an interval. He wasn’t wrong. Ken still can’t survive without the adulation.

“When I played the Palladium in 1965 a huge wave of welcome hit me. I didn’t think that London would welcome me. But the Palladium is actually a provincial theatre in London. It’s really working class.”

Not like the comedian himself, not his politics anyway, considering he was a one-time Thatcher devotee. But he won’t pick up on this paradox.

Okay, so what was there about Ken Dodd’s act that won over the legions? The gag rate is of course tremendous, (seven TPM - titters per minute) but unlike Britain’s other joke machine Bob Monkhouse, Doddy has funny bones, not just funny material.

“The trick is to polish the act like a jewel,” he says, “and you get to know what works for an audience.”

He may be an ace question avoider, but not all of the questions the comedian throws out to feature writers are about displacement.

In the last few moments of the chat, he asks, with genuine interest of my mother. “Do you speak to her every day? . . . Why not? . . . You really should you know. . . ”

Is it because he misses his own mum? “Oh, yes,” he says, for once in soft voice. What’s undeniable is Ken Dodd is a nice man, with a heart the size of Strawberry Fields, who lives to be laughed at.

“The shows aren’t so long these days,” he says, laughing of his value-for-money gigs reflected in his gags such as ‘I’ve seen children grow out of their trousers.’

“And you have to remember, there aren’t any locks on the doors. They can get up and leave any time they like.”

• The Ken Dodd Happiness Show, the Pavilion, June 25.