"But Doctor," Bill replied, "I feel great. I haven't felt better in years. This just can't be true. Isn't there anything I can do?"

After a moment the doctor said, "Well, you might start going down the street to that new health spa and take a mud bath every day."

Excitedly Bill asked, "And that will cure me?"

"No," replied the doctor, "but it will get you used to the dirt."