A man complained to his friend, "My elbow hurts. I better go to the doctor."
"Don't do that," volunteered his friend, "there's a new computer at the drugstore that can diagnose any problem quicker and cheaper than a doctor. All you have to do is put in a urine sample, deposit $10, then the computer will give you your diagnosis and plan of treatment."
The man figured he had nothing to lose, so he took a sample of urine down to the drugstore. Finding the machine, he poured in the urine and deposited $10. The machine began to buzz and various lights flashed on and off. After a short pause, a slip of paper popped out on which was printed:
You have tennis elbow. Soak your arm in warm water twice a day. Avoid heavy labor. Your elbow will be better in two weeks.
That evening as the man contemplated this breakthrough in medical science, he began to suspect fraud. To test his theory he mixed together some tap water, a stool sample from his dog and urine samples from his wife and teenage daughter. To top it all off, he masturbated into the jar. He took this concoction down to the drugstore, poured it in the machine and deposited $10. The machine went through the same buzzing and flashing routine as before then printed out the following message:
Your tap water has lead. Get a filter. Your dog has worms. Give him vitamins. Your daughter is on drugs. Get her in rehab. Your wife is pregnant. It's not your baby. Get a lawyer. And if you don't stop jerking off your tennis elbow will never get better.