When is it time to get on the medical intervention train and when should you leave well enough alone? As I have gotten older, and my friends have gotten older, every doctor visit feels like stepping on a train that will soon speed up so much you can't get off - so fast you can't even see the landscape outside the window anymore. Chronic medication, more tests...preventive examinations, just one more, just one more. I understand that these things prolong life, but how do you distinguish treatable medical conditions from normal aging? How do you go gently into that good night?