IT MAY not be as ancient as acupuncture, but homeopathy is the closest thing Germany has to a native alternative-medicine tradition. Practitioners line the high street. Upper-class Germans swear by it. Unusually, Germany gives homeopathy a privileged legal status. Whereas other medicines must meet scientific criteria, homeopathic remedies need not, and health insurers are explicitly allowed to reimburse for their use. This bothers sceptics such as Norbert Schmacke, a professor of medicine and the author of a book explaining why homeopathy is nonsense. “If you believe that water has memory,” as homeopaths do, you “might as well also believe in unicorns”, he says.

Such objections have been raised for much of the two centuries since Samuel Hahnemann, a Saxon doctor, invented homeopathy. He believed that “like cures like”—ie, that tiny doses of a toxin can heal the patient. And he did mean tiny: homeopaths dilute their chemicals into water or sugar to concentrations of 1 part to billions or even trillions. Usually not a single molecule remains in the preparation. Yet believers claim that this dilution makes the remedies stronger, provided that practitioners use the proper shaking technique.

Homeopathy’s renaissance started in the 1970s, when it was rediscovered by West Germany’s glitterati, including Veronica Carstens, the wife of a former German president. A big lobby sprung up. As homeopathy spread internationally, so did the controversies. Australia’s medical-research council last year came out firmly against the technique; Britain and Switzerland are still debating.

Nobody denies that some people are sincerely convinced they benefit from homeopathy. This is thanks to the placebo effect—the more one believes, the bigger the effect. But no respectable scientific study has ever shown anything beyond that. That is why a group of German professors and doctors, including Mr Schmacke, met in Freiburg earlier this year to issue a declaration. Homeopathy is “a stubbornly surviving belief system”, they argue, which “cannot explain itself” and relies on “self-deception” by patients and therapists.

At a conference in Bremen in May, the homeopathy lobby struck back, publishing a meta-analysis of research that supposedly proves homeopathy works. It contains old studies already debunked, the sceptics pointed out. As that fight rages on, politicians are becoming bolder. In August Josef Hecken, the chairman of the committee that governs what public health insurance can cover, said he favours banning homeopathy from the list. None of this will sway the faithful. “I’m not worried because I know that it works,” says Cornelia Bajic, the homeopathy lobby’s leader. She trusts her experience as a practitioner, she says, as well as the hordes of people showing up for treatment. In other words, if people think it works, it must work. Some might term such reasoning “superstition”.