A couple went to the hospital to give birth to a baby. The doctor told them when they arrived he had a new machine that would transfer some of the pain from the mother to the father.

Agreeing to do this, the doctor gave 10% of the pain to the father, saying that 10% would be more pain than he had ever felt. When the father didnt feel anything, the doctor bumped it up to 50%.

Still no pain, so up the doctor went to 100%, the wife gave birth painless and they went home. When they got to the door, the mail man was dead on their doorstep.