Beachcomber once ran an item under the heading "Six horses wedged in a chimney" that read: "The story to fit this sensational headline has not turned up yet." With Anatomy of Disgust (10pm, Tuesdays), I had a feeling that Channel 4, satiated with lust, hate and greed (and that's just Big Brother), had dreamt up the title and then set about commissioning programmes to fit. Fortunately, the director of this three-part series, Gary Johnstone, and his executive producer, Simon Andreae, soon convinced themselves that Darwin was right to classify disgust as a primary emotion. Val Curtis, an expert witness in these programmes, even asks us to cast a sympathy vote for "the forgotten emotion".
Like a good but somewhat dry essay, the first outing into this netherworld defined its terms. The programme boiled down a nature versus nurture discussion. How much is disgust innate and how much is it learnt? Disgust, as registered by the wrinkled nose, open-mouthed look of a baby who has just tasted lemon juice, certainly is universal. Dirt is matter out of place, and mankind is disgusted by items that cross the categories it imposes on the world: slime (half-solid, half-liquid), excreta (both of us and outside us), rotting food (the edible turned inedible). But, as the anthropologist Mary Douglas discovered when she married a Frenchman who was horrified by her habit of pouring baby wee down the kitchen sink, it has regional variations, too. The Japanese eat sea slugs, Hindus abhor beef, Jews won't touch pork, and so on.
However, if disgust is geographically nurtured, nobody has yet managed to programme a human being to find flowers disgusting or, with the possible exception of Gilbert and George, to arrange a bunch of faeces in a vase. The programme demonstrated, using real, live children, that while a two-year-old will happily eat a chocolate shaped like a dog turd, and even a four-year-old could be persuaded to, an eight-year-old will not touch it. We are, it seems, predisposed to pick up some prejudices and not others.
Some of the controlled experiments used to demonstrate this were more convincing than others. We were introduced to a video artist called Melanie who stops passers-by and asks for a kiss. She is refused 70 per cent of the time, and has received "a full-blown wet one" only once. Thus it was proved that the exchange of bodily fluids is inherently disgusting. All I can say is that Melanie cannot have been to the kind of teenage parties I went to, and that she should try the experiment again without the rubber balaclava on her head.
The first programme left you yearning for the more interdisciplinary approach of the next two instalments. The third and final programme discusses modern art's infatuation with disgust, but the second instalment, on disgust as a political weapon, is the strongest and most original. It argues that the identification of minorities or enemies as an object of physical disgust exploits a natural human willingness to stigmatise difference. And, cleverly, the argument is arranged so as to bring the point ever nearer home.
It begins with Rwandan Hutus condemning Tutsis as cockroaches, moves to India where 300 million people are still regarded as literally "untouchable", and then turns to Germany. Hitler identified the Jews with filth and vermin. The Germanic fascination with faeces is, in fact, ingrained: Luther, who wrote that he got his idea for the Reformation sitting on the pot, and Mozart, with his notoriously scatological letters, were not cultural exceptions, but the rule. Hitler, with his propaganda films set in clean, Alpine snow, was prophesying a Germany that had conquered its fatal fascination with squalor by exterminating it.
Then we are in present-day Britain, where the nail-bomber David Copeland admitted that he had attacked blacks and Asians out of political conviction, but that bombing gays in Soho was "personal". Copeland was no sociological aberration, either, or not much of one. In the street, a male gay couple kiss as passers-by are interviewed. Almost to a man, the word they use to describe this outrage against public decency is "disgusting".
The tone throughout the series is sober and learned. I hope the academics interviewed were rewarded, not least for the number of hats they wore. Curtis is variously described as an "evolutionary psychologist", an "evolutionary biologist" and a "lecturer in hygiene". In episode two, William Miller is a professor of law; by episode three, he has become a professor of medieval literature. Despite so many expert witnesses, the programme lacks a grand prosecutor, a Susan Greenfield or Jonathan Miller - or perhaps someone less cerebral, because there is a disappointing formality here, a lack of visual flair and fun. The programmes challenge us mentally, but not viscerally. They look too spanking clean.
Even as she recited universal examples of what is disgusting - dirty feet, mucus, cooking while menstruating (that's what she said) - Curtis could not help but look as wholesome as Dettol. Form should reflect content, and the programme-makers should have tried a little harder to disgust Tunbridge Wells.
Andrew Billen is a staff writer on the London Evening Standard