'Those who disagree should remember a lesson from the history of anti-smoking. Doll's post-war study was not the first to prove that smoking caused lung cancer: Nazi scientists had reached the same conclusion 20 years earlier. The resulting evidence was ignored in this country because it came from a tainted source. It was assumed that good science could not come from an evil regime. In the modern-day debate over secondary smoking, campaigners who pretend there is proof that it kills are repeating that historic error in reverse. Excellent motives are producing grotesquely distorted science'