It is classical scene, a detail of a mural from the ruins of Pompeii, from the first century BC. It is rather beautiful. But what on earth is it advertising? The answer is nothing. It has been placed there by the French federation of poster advertisers to defend the right of freedom of speech, and, more specifically, their right to use sexual imagery in posters. It carries the rather pompous slogan: "Freedom of expression begins on the walls." Six thousand similar posters can be found all over France this summer.
Paris has long outgrown its Anglo-Saxon reputation as a naughty city but it remains a hazardous city for the prudish. At every turn, on almost every bill-board, in almost every shop- window from chemists to bakers, you come across gleamingly attractive human body parts.
In France, it has long been the tradition of advertisers to serve tits with everything, with the occasional buttock to relieve the boredom. Sexual themes are employed to sell everything from cheese to mineral water. If a poster is selling jeans, the jeans are invariably all that the model wears. One celebrated television advertisement showed a woman caressing a bottle of sparkling water, which ultimately exploded in her hands. It was not possible to watch a football match on television last season without seeing Eric Cantona's bare bottom (advertising sports shoes).
Traditionally, this approach has been defended as a symptom of the relaxed and adult French attitude to sex, compared to the stuffy and complex-ridden views of the Anglo-Saxons. But, in recent years, there has been something of a backlash against the pervasiveness of sexuality in advertising in France. Two suggestive film posters, which also, in fact, appeared in other countries, were challenged in the French courts by family-values pressure groups, with some success. Even a socially liberal magazine like Le Nouvel Observateur complained that the lazy use of sex in advertising was making sex boring. Francoscopie, the annual bible of French trends and statistics, reported with alarm that a growing number of French people (between 15 and 20 per cent) said they had no interest in sex. The book blamed the preponderance of sexual images in the media, and especially in advertising, for "killing desire by banalising it ... By undressing people, they have robbed them of their mystery".
The French advertising industry has grown alarmed at criticism of its favourite method of selling. It has started an advertising campaign of its own, using spare poster sites during the summer lull, to assert its right to be obsessed by sex.
Officially the campaign is about freedom of expression in the broadest sense. There have been other campaigns in recent summers, on humanitarian and charitable themes, using spaces donated by the industry. Another of this year's free-speech posters shows a paleolithic imprint of a human hand from the wall of a recently discovered, submerged cave in the south of France.
But the advertisers concede that the choice of an erotic scene for one of this year's summer campaign posters was partly intended to defend their own right to use erotic imagery.
"If you interpret that particular poster that way, you would not be wrong," said Jean-Pierre Duval, the delegate-general of the French federation of poster and external advertising.
"But the campaign has a broader message and a broader motivation. It shows that advertisers are committed to freedom of expression, not just to selling clothes or cosmetics."