Sexually explicit material has always challenged traditional moralists. Since the Sixties, liberal values on sex and sexual relationships became one of the markers of a civilised society. Yet we learn from this debate, filmed at the Battle of Ideas, there is a growing unease that sexually explicit material has become mainstream. Some insist the likes of Rihanna and Katie Perry are simply the latest practitioners of age-old exhibitionism. But have sex and relationships become devalued and is the rush to smash sexual taboos a healthy impulse, or an expression of our unwillingness to exercise good taste?