In Imagine: Andy Warhol — Denied (BBC One), Alan Yentob was wondering: what must it feel like to buy an expensive painting by a famous artist, only to be told — after the artist has died, and the authentication of his work is in the hands of a cabal whose no-comeback verdicts can incinerate the value of a canvas — that your painting is deemed to be a fake? Who knows?

Actually Joe Simon, he knows.

Simon, an American film producer, bought a Warhol self-portrait for $195,000 and was planning to sell it a few years ago for $2million when a secretive body called the Andy Warhol Art Authentication Board decreed that it was not the work of Warhol — even though the canvas was signed by a Warhol associate confirming its provenance. This verdict effectively rendered Simon’s painting as valuable as a breath mint. Yentob tugged at this loose thread to unravel an Alice in Wonderland world in which a genuine Warhol is, in Humpty Dumpty fashion, exactly what the Andy Warhol Art Authentication Board chooses to be a genuine Warhol, neither more nor less.

The Manhattan-based art historian John Richardson, a friend of Warhol’s, owns several paintings that Warhol gave to him as presents, but says he wouldn’t “dare submit these things to the board for fear of being told they’re not by Andy”. The Authentication Board’s judgments seem so capricious that you wonder if its work isn’t some kind of performance art, a deathbed prank bequeathed by Warhol to make a continuing mockery of the art establishment.

Richardson, in any case, queries the very concept of authenticity in relation to an artist who mass-produced art the way Warhol did — and who did it so shamelessly that he even named his studio The Factory. “He used to do these silk screens,” Richardson explains, “and assistants would come in at night and run off a few copies for themselves. But did that make them any less authentic than the ones they ran off for Andy during the day?”

Not only did Warhol mass- produce art, he often couldn’t be bothered to sign it. So friends stepped in; with surreal consequences. “I’ve heard that Sotheby’s will authenticate an ‘S&H Green Stamp’ poster if it has my forged Andy Warhol signature on it,” says Warhol’s friend, Sam Green. “If somebody else has forged the signature, then it’s not an Andy Warhol.”

The trail of Joe Simon’s Warhol offered Imagine a handy way of exploring a hall of mirrors in which, for instance, a Van Gogh Sunflowers can make the art world swoon one day, only for the same painting to leave everyone cold (and to become all but worthless) if it is later decided that Van Gogh did not paint it himself. So, then, what of all the fakes hanging on museum walls? Is there something bogus about our enjoyment of them? Can enjoyment be bogus?

But when it comes to playing with people’s perceptions by passing one thing off as maybe something else, wasn’t it curious that the grand house from which Yentob was conducting his research and making his phone calls, padding up and down the stairs as if we were eavesdropping on him at home, looked to be the house that is actually owned by the architect Richard Rogers?

In Alternative Medicine: The Evidence (BBC Two), Professor Kathy Sykes, of Bristol University, decided to test whether alternative medicine deserves to be as popular as it is becoming, or whether it’s so much quackery. Many alternative therapies certainly seem hokum. But you would think that even a scientist might concede that there must be something to acupuncture, a technique the Chinese have been using for 2,000 years — especially when the opening sequence of Sykes’s documentary showed a young woman in a Chinese hospital having her chest yanked open for major heart surgery with only a quiver of acupuncture needles to kill (very successfully) the pain of the scalpel.

After an hour’s worth of globe- trotting, experimentation and monitoring of state-of-the-art brain scanners, Sykes conceded that, hey, there might be something in it. “I started off pretty sceptical about acupuncture,” she tells us at the end. “It just didn’t make sense from a scientific point of view.” It’s an approach that betrays one of the arrogant aspects of science: science believes something exists only if it can prove it exists. Isn’t this a bit like saying gravity existed only once Newton proved it existed? Or even that a Warhol is only a great work of art if it is blessed as a Warhol by the Andy Warhol Art Authentication Board?

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