As the US right hurls ever more fantastic slippery slope arguments at health care reform, the Atlantic's James Fallows has challenged readers to come up with a single non-specious example of a metaphorical slippery slope. Aside from, "birth leads inevitably to death," they've been pretty much stumped. But one reader offered this 19th century advice from Thomas de Quincey, author of Confessions of an Opium Eater. If once a man indulges himself in murder, very soon he comes to think little of robbing; and from robbing he comes next to drinking and Sabbath-breaking, and from that to incivility and procrastination. Once begun...